記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s13758-012-0027-9

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1111/j.1600-0501.2011.02163.x

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.tripleo.2005.03.007

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/jbm.a.30110

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1111/j.1600-0501.2004.01015.x

掲載種別：研究論文（学術雑誌）  

DOI： 10.1034/j.1600-0501.2002.130303.x

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1902/jop.2000.71.6.961

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/(SICI)1097-4636(199807)41:1<111::AID-JBM14>3.0.CO;2-Q

記述言語：英語   出版者・発行元：日本大学歯学部  

記述言語：英語   出版者・発行元：日本大学歯学部  

記述言語：英語   出版者・発行元：Biointerphases  

The long-term stability of dental implants is significantly influenced by their resistance to foreign factors in the peri-implant epithelium (PIE). Despite this, enhancing the sealing properties at the implant-PIE interface continues to be an unmet clinical need. Ti-6Al-4V (Ti64) alloy has higher tensile strength and hardness than pure titanium. This study was to verify whether hydrothermal treatment of Ti64 alloy implants with distilled water (HT-DW) or calcium chloride (CaCl2) solution (HT-Ca) could improve the sealing of the PIE around Ti64 implants. The existence of calcium (Ca) on the surface of HT-Ca implants was confirmed using x-ray photoelectron spectroscopy and synchrotron-based x-ray absorption fine structure techniques. These data showed that the surface was oxidized, and Ca existed in the form of anhydrous CaCl2 and calcium titanate. Laminin-332 (Ln), which is an essential component of epithelial adhesion structures, was observed between all types of implants and the PIE, 4 weeks after implantation in rat maxillae. Ln distribution over the entire epithelial interface was similar for the HT-Ca implant and a natural tooth. Moreover, the HT-Ca implant inhibited foreign body penetration, which indicated stronger gingival sealing at the implant-PIE interface, compared with the untreated and HT-DW implants. We also investigated the attachment of mouse-derived gingival epithelial cells (GE1). GE1 adherence was stronger and Ln expression levels were higher for HT-Ca plates compared with the untreated and HT-DW plates. Our results demonstrate that hydrothermal treatment of Ti64 implants with CaCl2 solution facilitates the growth of an effective soft tissue seal around the implant.

DOI： 10.1116/6.0004359

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記述言語：英語   出版者・発行元：Biointerphases  

The long-term stability of dental implants is significantly influenced by their resistance to foreign factors in the peri-implant epithelium (PIE). Despite this, enhancing the sealing properties at the implant-PIE interface continues to be an unmet clinical need. Ti-6Al-4V (Ti64) alloy has higher tensile strength and hardness than pure titanium. This study was to verify whether hydrothermal treatment of Ti64 alloy implants with distilled water (HT-DW) or calcium chloride (CaCl2) solution (HT-Ca) could improve the sealing of the PIE around Ti64 implants. The existence of calcium (Ca) on the surface of HT-Ca implants was confirmed using x-ray photoelectron spectroscopy and synchrotron-based x-ray absorption fine structure techniques. These data showed that the surface was oxidized, and Ca existed in the form of anhydrous CaCl2 and calcium titanate. Laminin-332 (Ln), which is an essential component of epithelial adhesion structures, was observed between all types of implants and the PIE, 4 weeks after implantation in rat maxillae. Ln distribution over the entire epithelial interface was similar for the HT-Ca implant and a natural tooth. Moreover, the HT-Ca implant inhibited foreign body penetration, which indicated stronger gingival sealing at the implant-PIE interface, compared with the untreated and HT-DW implants. We also investigated the attachment of mouse-derived gingival epithelial cells (GE1). GE1 adherence was stronger and Ln expression levels were higher for HT-Ca plates compared with the untreated and HT-DW plates. Our results demonstrate that hydrothermal treatment of Ti64 implants with CaCl2 solution facilitates the growth of an effective soft tissue seal around the implant.

DOI： 10.1116/6.0004359

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記述言語：英語   出版者・発行元：日本大学歯学部  

記述言語：英語   出版者・発行元：公益社団法人 日本補綴歯科学会  

<p><b>Purpose:</b> To compare abutment and scan body subsidence and determine the appropriate tightening torque value for a scan body that can accurately replicate abutment subsidence.</p><p><b>Methods:</b> An internally tapered connection implant was placed in a bone model. The titanium abutment (Ti Abut), polyetheretherketone scan body (PEEK SB), and titanium scan body (Ti SB) were tightened to torque values of 10 or 35 Ncm, with the 10 Ncm models used as reference models. Both the 10 and 35 Ncm models were scanned using a laboratory scanner. The vertical displacements of the Ti Abut, PEEK SB, and Ti SB at each torque value were determined using three-dimensional analysis software.</p><p><b>Results:</b> Upon tightening the scan bodies and abutment to 35 Ncm, the displacement was significantly greater than when tightened to 10 Ncm (<i>P</i> < 0.01). At 35 Ncm, Ti SB and Ti Abut showed significantly greater displacements than PEEK SB, whereas no significant difference was observed between Ti SB and Ti Abut.</p><p><b>Conclusions:</b> The titanium scan bodies, when tightened at 35 Ncm, accurately replicated titanium abutment subsidence, unlike the PEEK scan bodies.</p>

DOI： 10.2186/jpr.jpr_d_24_00224

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記述言語：英語   出版者・発行元：日本大学歯学部  

Purpose: The present study investigated the effects of stabilization splints on two categories of sleep bruxism using a portable electromyographic recording system. Methods: Twenty-six individuals confirmed as mild to severe bruxers by nocturnal masseter electromyographic episodes were enrolled in the study. Participants wore a stabilization splint during sleep for 30 nights, and mas-seter muscle activity was measured at baseline, immediately after, and 1 and 4 weeks after insertion of the splint. Bursts in masseter electromyographic episodes were separated into phasic bursts or tonic bursts, then each burst was analyzed in terms of duration, frequency, and magnitude of bursts. Results: The frequency of phasic bursts significantly decreased immediately after insertion of the splint compared with the baseline. The geometric mean magnitude of tonic bursts decreased when wearing the splint compared with the baseline. Conclusion: These findings suggest that stabilization splints reduce jaw-muscle activity during sleep in patients suffering from sleep bruxism by reducing the frequency of phasic bursts in the short term and reducing the magnitude of tonic bursts over a longer period.

DOI： 10.2334/josnusd.24-0233

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記述言語：英語   出版者・発行元：日本大学歯学部  

Purpose: The purpose of this study was to analyze the association between the number of medications and oral functions. Methods: The study participants were selected from individuals who were attending regular follow-up as hospital outpatients. Patient profiles, the number of medications used, and measured values of oral function were extracted. These data were analyzed statistically for sex, age, and grouping according to the number of medications taken (no medication, G1; 1-4 medications, G2; ≥5 medications, G3). Conditional logistic regression analysis was performed to evaluate the effects of medications on oral function. Results: A total of 172 patients (66 males and 106 females) were regis-tered; 50 participants belonged to G1, 68 to G2, and 54 to G3. Significant inter-group differences were identified for tongue-lip motor function (oral diadochokinesis: ODK) and maximum tongue pressure in terms of age, but not in terms of sex. G3 showed significantly lower ODK than G1, and logistic regression analysis revealed that the number of medications was significantly associated with ODK/pa/. Age and MTP also significantly affected ODK/ta/ and /ka/. Conclusion: Within the limitations of this study, the present findings suggest that the number of medications taken has an impact on tongue-lip motor function.

DOI： 10.2334/josnusd.24-0281

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記述言語：日本語   出版者・発行元：公益社団法人 日本口腔インプラント学会  

DOI： 10.11237/jsoi.37.85

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記述言語：日本語   出版者・発行元：(公社)日本口腔インプラント学会  

上顎骨と比較して下顎骨は硬く,インプラントの初期固定が得られやすいと考えられている.しかし,パノラマエックス線やCTの画像所見にて,欠損部の骨梁に顕著な透過像が認められなかったにもかかわらず,インプラント体の迷入を経験した.また,他院にて迷入したインプラント体を撤去する機会を得たため,これら2症例について報告する.症例1は52歳の女性,低速でインプラントを埋入中に迷入が生じた.印象用のガイドピンを使用し,形成窩から引き上げてインプラント体を撤去した.症例2は35歳の女性,晩期残存した乳歯の抜去後インプラントを即時埋入し,トルクレンチで深度調整中にインプラント体が迷入した.迷入後のCT画像データから3D模型を作製後,下歯槽神経の損傷に配慮した骨削合のデザインを検討し,骨を切り出してインプラント体を撤去した.2症例ともに後遺症は認めなかった.術前のパノラマエックス線写真やCTなどの画像所見からインプラント体の迷入を推測できる場合もある.しかし,予測が困難な場合は術中の埋入窩形成時の手指感覚から形成アプローチを勘案することが重要である.迷入したインプラント体の撤去には,埋入窩から取り出すcrestal approachと下顎骨の外側の骨を切離して取り出すlateral approachの2つの方法がある.これらはCT所見からインプラント体と神経の走向関係を把握したうえで適切に選択し,可能なかぎり早い時期にインプラント体の撤去を行うことが望ましいと考える.(著者抄録)

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Evidence-Based Dental Practice  

Objectives: An increasing number of studies have identified an association between oral health status and cognitive function. However, the effect of oral interventions, including oral health care, dental treatment and oral motor exercises, on cognitive function remains unclear. This systematic review examined whether oral interventions contribute to the long-term improvement of cognitive status. Methods: Four databases were searched (MEDLINE, Web of Science, Cochrane Library, and ICHUSHI Web) to identify randomized and nonrandomized controlled trial studies and prospective cohort studies from inception until 1 September 2023, published in English or Japanese. The Cochrane risk of bias tool for randomized controlled trials and the risk of bias assessment tool for nonrandomized studies were used to assess bias risk. Results: A total of 20 articles were included in the qualitative analysis; 13 articles were published in English, and 7 were published in Japanese. The implemented interventions were oral care in 8 studies, dental treatment in 8 studies, and oral motor exercise in 4 studies. One study found a significant effect on attention following oral care intervention. Some dental treatments influenced cognitive function, although a clear positive effect was not determined. In 1 study, attention and working memory improved in the chewing exercise group. Conclusions: Several studies verified the improvement effects of oral interventions, such as oral care, dental treatment, and oral motor exercise, on cognitive function or impairment. However, there was still a lack of conclusive evidence that such an intervention clearly improved cognitive function. To clarify the effects of oral interventions on cognitive function, it is necessary to examine participants, interventions, and outcome measures in detail.

DOI： 10.1016/j.jebdp.2023.101948

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記述言語：その他   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACS Biomaterials Science and Engineering  

This study aimed to evaluate the bioactivity of poly(ether ether ketone) (PEEK) after surface modification by persistent photoconductive strontium titanate (SrTiO3) magnetron sputtering and ultraviolet (UV) C irradiation. According to the different modifications, the PEEK specimens were randomly divided into five groups (n = 38/group): PEEK, Sr100-PEEK, Sr200-PEEK, UV/PEEK, and UV/Sr200-PEEK. Then, the specimens of Sr100-PEEK and Sr200-PEEK groups were, respectively, coated with 100 and 200 nm thickness photocatalyst SrTiO3 on the PEEK surface by magnetron sputtering. Subsequently, UV-C light photofunctionalized the specimens of PEEK and Sr200-PEEK groups to form UV/PEEK and UV/Sr200-PEEK groups. The specimens were characterized by a step meter, scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive X-ray spectroscopy (EDX), and a water contact angle meter. The release test of the Sr ion was performed by inductively coupled plasma mass spectrometry (ICP-MS). In vitro study, osteogenic activity (MC3T3-E1 osteoblast-like cells) and epithelial and connective tissue attachment (gingival epithelial cells GE1 and fibroblasts NIH3T3) were analyzed in five groups. Surface morphology of the specimens was changed after coating, and the Sr content on the Sr-PEEK surface was increased with increasing coating thickness. In addition, the contact angle was increased significantly after magnetron sputtering. After UV-C photofunctionalization, the content of surface elements changed and the contact angle was decreased. The release of Sr ion was sustained, and the final cumulative release amount did not exceed the safety limit. In vitro experiments showed that SrTiO3 improved the cell activity of MC3T3-E1 and UV-C irradiation further enhanced the osteogenic performance of PEEK. Besides, UV-C irradiation also significantly promoted the cell viability, development, and expression of adhesion proteins of GE1 and NIH3T3 on PEEK. The present investigation demonstrated that nano SrTiO3 coating with UV-C photofunctionalization synergistically enhanced the osteogenic properties and soft tissue sealing function of PEEK in vitro.

DOI： 10.1021/acsbiomaterials.3c01684

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記述言語：英語   出版者・発行元：日本大学歯学部  

年齢が20～49歳でEichner分類がAの患者を対象に、口腔機能を表す3種の指標を解析した。2020年4～11月に福岡市にある単一の開業歯科医院を受診した上記患者183名(女性133名、平均34.0±7.7歳)のデータを後ろ向きに抽出した。口腔機能の指標としては、最大咬合力(MOF)、最大舌圧(MTP)、咀嚼機能を測定した。咀嚼機能はグミゼリー(グルコラム)からのグルコース溶出濃度として計測した。口腔機能低下症の診断基準となる閾値として、MOFでは500N、MTPでは30.0kPa、咀嚼機能では100mg/dLという値を設定した。全集団における3指標の平均値はいずれも閾値より高くなった。個々の患者でみると閾値を下回った患者はMTPで最も多く30名に上り、MOFでは19名、咀嚼機能ではわずかに3名のみであった。20、30、40歳代の年齢層別で比較したが、どの口腔機能指標にも有意な差はみられなかった。また男女比較ではどの口腔機能指標も女性より男性の方が有意に高かった。2種の口腔機能指標が共に閾値を下回っていた患者は9名いた。いずれも女性患者であり、うち8名は歯列不正を伴っていた。以上のように、一部の患者では、不便を自覚していないにもかかわらず口腔機能、特にMOFとMTPの値が低下していた。歯列不正は口腔機能低下に関連していると考えられた。

記述言語：英語   出版者・発行元：日本大学歯学部  

PURPOSE: The purpose of this study was to analyze oral functions (MOF: maximum occlusal force; MTP: maximum tongue pressure; and MF: masticatory function) in Eichner A subjects aged from 20 to 49 years. METHODS: The data of three oral functions in Eichner A patients aged from 20 to 49 years were extracted. The mean values, subjects with lower values than the thresholds, and the differences among ages, and between sexes were investigated retrospectively. RESULTS: Although the mean values of these oral functions in 183 subjects were higher than the thresholds, the numbers of the subjects with lower values than the thresholds were 30 in MTP, 19 in MOF, and only three in MF. No significant effects of ages on all oral functions were identified and all functions in males were significantly higher than those in females. The subjects whose two functions were lower than the thresholds were nine females, eight of whom were associated with malalignment. CONCLUSION: Although the mean values of oral functions were higher than the thresholds, some patients showed lower values, especially in MOF and MTP, even though they were unaware of any inconvenience. Patients with malalignment might be associated with declined oral functions.

DOI： 10.2334/josnusd.23-0311

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記述言語：英語   出版者・発行元：Healthcare (Switzerland)  

“Combination syndrome”, defined by Kelly in 1972, is a challenging condition observed in a patient with an edentulous maxilla and a partially edentulous mandible with only mandibular anterior teeth. “Anterior hyperfunction syndrome” is regarded as a synonym of combination syndrome and was first described in 1994. Although these terms have been well known, the definition of “anterior hyperfunction” has not been described yet. This narrative review focused on anterior hyperfunction and discussed the etiology and the clinical managements. An electronic bibliographic search for this literature review was conducted in addition to the review of our clinical cases. The previous reports indicated that combination syndrome with all five features was rarely observed. The patients with anterior hyperfunction generally showed the loss of posterior occlusal supports and the loss of vertical dimension of occlusion. To manage anterior hyperfunction, these conditions should be improved using conventional removable prostheses and implant-supported prostheses. Anterior hyperfunction is attributed to mandibular anterior teeth and some interventions for mandibular anterior teeth are required in many cases. Additionally, it must be noted that implant-supported prostheses may lead to anterior hyperfunction. In conclusion, comprehensive approaches for the remaining teeth and the prostheses will be required to manage this complex condition.

DOI： 10.3390/healthcare11222967

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記述言語：英語   出版者・発行元：Journal of Clinical Medicine  

The aim of this retrospective cross-sectional study was to comprehensively assess masticatory function in maxillectomy patients with functioning removable prostheses. Their general and oral profiles, the measurement values of their oral functions, including masticatory function, and the history of tumor therapy were extracted from medical charts. The correlations of masticatory function with numerical data and the effects of tumor therapy-related factors on masticatory function were evaluated. In addition, a stepwise conditional logistic regression analysis was performed to identify the potential predictive factors comprehensively. The data from 55 maxillectomy patients revealed that the median value of masticatory function (138.0 mg/dL) was higher than the threshold (100.0 mg/dL) based on the concept of oral hypofunction. Moderate correlations of masticatory function with the number of remaining teeth, the number of functioning occlusal supports, and maximum occlusal force were found, as well as a weak correlation with maximum tongue pressure. These variables also showed statistically significant coefficients (p < 0.01). No significant effect of each tumor therapy-related factor on masticatory function was detected. A logistic regression analysis identified the number of functioning occlusal supports as a significant predictive factor. These results implied the crucial interactions of masticatory function with various factors and the specificities of maxillectomy patients.

DOI： 10.3390/jcm12155117

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Prosthodontic Research  

PURPOSE: The aim of this study was to review the literature on current surface modification strategies used to improve the binding efficiency of an emerging biological material, polyetheretherketone (PEEK), with bone and soft tissues. STUDY SELECTION: This review was based on articles retrieved from PubMed, Google Scholar, Web of Science, and ScienceDirect databases. The main keywords used during the search were "polyetheretherketone (PEEK)," "implant," "surface modification," "biomaterials," "bone," "osseointegration," and "soft tissue." RESULTS: The suitability of PEEK surface modification strategies has been critically analyzed and summarized here. Many cell and in vivo experiments in small animals have shown that the use of advanced modification technologies with appropriate surface modification strategies can effectively improve the surface inertness of PEEK, thereby improving its binding efficiency with bone and soft tissues. CONCLUSIONS: Surface modifications of PEEK have revealed new possibilities for implant treatment; however, most results are based on in vitro or short-term in vivo evaluations in small animals. To achieve a broad application of PEEK in the field of oral implantology, more in vivo experiments and long-term clinical evaluations are needed to investigate the effects of various surface modifications on the tissue integration ability of PEEK to develop an ideal implant material.

DOI： 10.2186/jpr.JPR_D_22_00138

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記述言語：日本語   出版者・発行元：公益社団法人 日本口腔インプラント学会  

<p>口腔インプラント治療は欠損補綴において重要な選択肢となっている．インプラント体を口腔内で機能させるためには骨組織との結合性が重要であることは以前から知られているが，その機能を長期間継続させるには軟組織による封鎖性が不可欠であることも忘れてはいけない．この封鎖機構は，天然歯周囲に存在する生物学的幅径と類似した構造を有している．しかし，インプラント周囲における封鎖機能は，天然歯周囲と比較して明らかに低く脆弱である．その原因として，骨に直接埋入される口腔インプラントの周囲では歯根膜が存在せず，解剖学的に血流が不足していることが挙げられる．さらに組織学的にインプラント体と接着する上皮などの封鎖構造が天然歯と比べて明らかに限局的で少なく，上皮細胞のチタンに対する接着性がそもそも低いことなどから，わずかに存在する接着構造も封鎖機能が低いとされている．そのため，このインプラント周囲における軟組織封鎖性を向上させるため，インプラント体の材質，表面性状，さらに周囲組織の細胞活性に関するさまざまな研究が現在も進められているわけである．このような基礎的研究に対する理解は，適応症例の選別やインプラント体や手技の選択，さらには軟組織を考慮したメインテナンスの実践に役立ち，インプラント治療の長期間の成功につながると期待している．</p>

DOI： 10.11237/jsoi.36.32

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人　日本歯科理工学会  

Carbonate apatite (CO3Ap) is a major inorganic bone component and an effective bone substitute. To clarify the function of CO3Ap, we compared differences among CO3Ap, hydroxyapatite (HAp), and β-tricalcium phosphate (β-TCP) by focusing on mesenchymal stem cells (MSCs) that have a role in wound healing. For in vivo experiments, maxillary molars were removed and the bone substitute was inserted. MSC accumulation around extraction sockets was significantly promoted in CO3Ap and β-TCP groups. For in vitro experiments, MSCs were cultured with bone substitutes. The differentiation potential and amount of calcium deposition were significantly lower in CO3Ap and HAp groups than in the β-TCP group. Increases in insulin-like growth factor-I and vascular endothelial growth factor were found only in the CO3Ap group. CO3Ap-filled extraction sockets accumulated MSCs, and MSCs cultured in the presence of CO3Ap produced large amounts of growth factors. These results suggest that CO3Ap promotes healing of tooth extraction sockets.

DOI： 10.4012/dmj.2022-040

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   出版者・発行元：(公社)日本口腔インプラント学会  

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記述言語：英語   出版者・発行元：(一社)日本歯科理工学会  

骨補填材としての炭酸アパタイト(炭酸Ap)をハイドロキシアパタイト(HAp)およびβリン酸三カルシウム(β-TCP)と比較し、間葉系幹細胞(MSC)に注目してそれらの間にみられる差異を検討した。6週齢の雄性ラット30匹を使用してin vivo実験を施行した。上顎の第1・2大臼歯を抜歯し、抜歯窩に上記3種の骨補填材のいずれかを移植した。その3日後と7日後に深麻酔死させ各種の評価に供した。その結果、炭酸Ap群とβ-TCP群では、抜歯窩付近のMSCの集積が有意に促進された。MSCを骨補填材の存在下で培養するin vitro実験も行ったところ、炭酸Ap群とHAp群では分化能とカルシウム沈着量がβ-TCP群よりも有意に低減していた。インスリン様成長因子I(IGF-I)と血管内皮細胞増殖因子(VEGF)が増加しているという結果は炭酸Ap群のみで認められた。炭酸Apを充填した抜歯窩にはMSCが集積し、炭酸Ap存在下で培養したMSCは成長因子類を大量に産生したことから、炭酸Apは抜歯窩の治癒を促進することが示唆された。

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：mSphere  

The tongue dorsum is colonized by a stable microbiota, mostly comprising common commensal taxa. However, the predominance of each taxon varies among individuals. We hypothesized that equilibrium in the tongue microbiota is affected by exposure to butyrate in the oral fluid, which is reported to affect the growth of specific microorganisms. In this study, the bacterial composition of the tongue microbiotas of 69 male adults was determined via 16S rRNA gene sequencing to investigate its relationship to n-butyric acid concentration in oral rinse samples. The tongue microbiotas of individuals with a higher n-butyric acid level had higher relative abundances of Prevotella histicola, Veillonella atypica, and Streptococcus parasanguinis and lower relative abundances of Neisseria subflava and Porphyromonas pasteri. Subsequently, tongue microbiota samples collected from 12 adults were cultivated for 13 h in basal medium containing mucin and different concentrations of sodium butyrate (0, 0.8, 1.6, and 3.2 mM) to assess its effect on the growth of tongue microbiota organisms. The bacterial composition of the cultivated tongue microbiotas also demonstrated a significant gradual shift with an increase in sodium butyrate levels in beta-diversity analysis. N. subflava was significantly less predominant in the microbiota after cultivation with an increased addition of sodium butyrate, although no statistical difference was observed in the other aforementioned taxa. These results suggest that butyrate in the oral fluid is partially involved in the dysbiotic shift of the tongue microbiota. IMPORTANCE Oral microbial populations that are always ingested with saliva have attracted increasing attention because more oral microorganisms than previously known reach distal organs, such as the lungs and intestinal tract, thereby affecting our health. However, although such organisms are predominately derived from the tongue dorsum, the dynamics and determinants of the tongue microbiota composition remain unclear. This study demonstrated that exposure to butyrate could lead to a dysbiotic shift in the tongue microbiota using an observational epidemiological and microbiota cultivation approach. This result adds a new dimension to tongue microbiota ecology.

DOI： 10.1128/msphere.00490-22

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記述言語：日本語   出版者・発行元：公益社団法人 日本補綴歯科学会  

<p>　公益社団法人日本補綴歯科学会では，教育問題検討委員会を中心として一般社団法人日本歯科専門医機構が求める，補綴歯科専門医を育成するためにふさわしい教育カリキュラムの構築を進めてきたが，このたびカリキュラムが概ね完成したことから，第131回学術大会でそのあらましを報告した．セミナーでは時間の制約もあり，お伝えできなかった項目もあることから，本稿は改めて会員の先生方に教育カリキュラムの内容を知っていただく目的で執筆した．</p><p>　補綴歯科専門医制度のカリキュラム設計は，ファンダメンタルとして補綴歯科専門医の基本知識・技能を学修する基本研修があり，そのうえに大きく分けて症例を基準とした「ケースシリーズベース評価」と，補綴歯科専門医が満たすべき能力の視点からの「コンピテンスベース評価」の二本立ての評価を行う．これらの評価や学習到達度については，いわば実習帳ともいうべき「補綴歯科専門医研修評価記録」に整理する．本稿では主に補綴歯科専門医研修評価記録の記載方法について概説しつつ，機構認定の補綴歯科専門医資格取得に必要な単位，試験について解説する．</p><p>　現在このカリキュラムは各研修機関で試用を行っており，内容の矛盾点や運用上の問題点の改善のために随時改訂を行っていく予定であるが，基本骨格については概ね固まっていると考えていただいて差し支えない．若手補綴歯科医の指導や，教育を受ける若手歯科医師の参考にしていただきたい．</p>

DOI： 10.2186/ajps.15.19

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記述言語：英語   出版者・発行元：John Wiley & Sons Australia, Ltd  

2009～2015年に包括的健康診断に参加した地域在住高齢者1240名(男性539名、平均76.6±7.1歳)を対象として、現在歯数および機能歯数と将来における自立喪失の発生率との関連について検討した。主要評価項目は自立喪失の発生(初回要支援要介護認定と定義)とした。調査項目は口腔内検査による現在歯数(1～9本、10～19本、20本以上)および機能歯数(0～19本、20本以上)、人口統計学的特徴、各種臨床変数(慢性疾患の既往、心理社会的要因)、血液栄養マーカー、身体機能、知覚的咀嚼機能などとした。最終的に1121名を解析対象とした。その結果、追跡調査期間中に205名に自立喪失が認められた。カプランマイヤー解析の結果、現在歯数および機能歯数が少ない者では、現在歯数または機能歯数が多い者と比較して、自立喪失の発生率が有意に大きかった。Cox比例ハザード分析の結果、人口統計学的特徴による調整後、現在歯数の少なさは自立喪失の発生の有意な危険因子でなかったが、機能歯数は有意な危険因子であることが示された(ハザード比:1.975)。以上から、機能歯数は現在歯数と比較して将来における自立喪失の発生率と密接に関連している可能性が示された。

記述言語：その他   掲載種別：研究論文（学術雑誌）   出版者・発行元：Geriatrics and Gerontology International  

Aim: To examine the relationship between the number of present and functional teeth at baseline and future incidence of loss of independence. Methods: Participants were community-dwelling older individuals who participated in a comprehensive geriatric health examination conducted in Kusatsu town, Japan, between 2009 and 2015. The primary endpoint was the incidence of loss of independence among participants, defined as the first certification of long-term care insurance in Japan. The numbers of present and functional teeth at baseline were determined via an oral examination. Demographics, clinical variables (e.g., history of chronic diseases and psychosocial factors), blood nutritional markers, physical functions, and perceived masticatory function were assessed. Results: This study included 1121 individuals, and 205 individuals suffered from loss of independence during the follow-up period. Kaplan–Meier estimates of loss of independence for participants with smaller numbers of present and functional teeth were significantly greater than for those with larger numbers of teeth. Cox proportional hazard analyses indicated that a smaller number of present teeth was not a significant risk factor after adjusting for demographic characteristics. However, the number of functional teeth was a significant risk factor after the adjustment (hazard ratio: 1.975 [1.168–3.340]). Additionally, higher hazard ratios were observed in other adjusted models, but they were not statistically significant. Conclusions: The number of functional teeth may be more closely related to the future incidence of loss of independence than the number of present teeth. This novel finding suggests that prosthodontic rehabilitation for tooth loss possibly prevents the future incidence of this life-event. Geriatr Gerontol Int 2022; 22: 1032–1039.

DOI： 10.1111/ggi.14508

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その他リンク： https://onlinelibrary.wiley.com/doi/full-xml/10.1111/ggi.14508

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Materials  

Bone augmentation using artificial bone is an important option in dental defect prostheses. A bone substitute using carbonate apatite (CO3Ap), an inorganic component of bone, was reported to have promising bone formation and bone replacement ability. However, the osteoinductivity of artificial bone is less than autogenous bone (AB). In this study, CO3Ap with AB is demonstrated as a clinically effective bone substitute. For in vitro experiments, an osteoclast-like cell (RAW-D) was cultured in the presence of AB, CO3Ap, or both (Mix), and the number of osteoclasts was evaluated. Osteoblasts were also cultured under the same conditions, and the number of adherent cells was evaluated. For in vivo experiments, a few holes were created in the rat tibia and AB, CO3Ap, or Mix were added. At 0, 14, and 21 days, the tissue morphology of the wound area was observed, and the thickness of the cortical bone was measured. In vitro, Mix did not increase the number of osteoclasts or osteoblasts. However, in vivo, the rate of bone replacement remarkably increased with Mix on dome-shape. A bone-grafting material combining osteoinductive AB with abundant artificial bone is expected to be clinically easy to use and able to form bone.

DOI： 10.3390/ma15228100

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記述言語：英語   出版者・発行元：Materials  

In the intraoral scanner (IOS) impression technique for dental implants, a scanbody (SB) is connected to the implant and scanned. Poly(ether-ether-ketone) (PEEK) is a widely used material for SBs and it is recommended for single use. However, from the perspective of the Sustainable Development Goals, it is desirable to use these products multiple times. As SBs are used in patients’ mouths, proper sterilization is necessary for multiple uses. In the present study, the effect of autoclave treatment and connection/disconnection on SB deformation was investigated. The SB was connected to the implant and stereolithography (STL) data were obtained. Then, the SB was disconnected and underwent autoclave treatment, or was connected and disconnected multiple times, or underwent a combination of both processes. The results showed that there were significant differences in the distance and angle when comparing SBs before and after the autoclave treatment, but repeated connections with or without autoclave treatment had no significant impact on the measured values. The surface texture, observed with scanning electron microscopy, showed that a groove was observed on the surface of the SB, but the groove did not show major changes after 10 connection/autoclave processes. These results indicate that autoclave sterilization has some impact on SB deformation but connection/disconnection itself may not have a huge impact on SB deformation.

DOI： 10.3390/ma15217717

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Healthcare (Switzerland)  

The clinical remount is an accurate and efficient way to reset the occlusion of delivered removable dentures if major occlusal correction is required. Although previous studies have reported that clinical remounting of existing dentures enhances patients' oral function, little subjective feedback is available. This retrospective study reports short-term changes in oral-health-related quality of life (OHRQoL) and masticatory function after clinical remounting of existing dentures. Three time points were defined: before adjustment (T0), immediately after adjustment (T1), and 1 week after adjustment (T2). The medical records of seven patients were analyzed. The mean age of participants was 77.71 years, and the mean service period of their prostheses was 9.43 months. The mean scores of the OHIP-EDENT-J questionnaire at the respective time points were 35, 21.14, and 22.14. The mean readings of masticatory function at the respective time points were 76.71, 89.29, and 111.86. Significant differences in the OHIP-EDENT-J were found between T0 and T1, and T0 and T2; and in masticatory function between T1 and T2, and T0 and T2. The results indicated that after rebalancing of the occlusion of the existing dentures, the patient-reported OHRQoL was improved immediately and maintained at least for a short time, and masticatory function was enhanced over a 1-week period.

DOI： 10.3390/healthcare10101960

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記述言語：英語   出版者・発行元：日本大学歯学部  

単一臼歯へのモノリシックジルコニア冠(MZC)とその対合歯の3年累積生存率を評価し、同生存率に影響している要因を解析した。2014年4月～2020年9月に当大学病院で単一臼歯へのMZC修復治療を行った患者105名(女性80名、平均64.2±11.3歳)の177冠を後方視的に組み入れた。MZC失敗の定義は、抜歯などでのMZCの撤去とした。対合歯失敗の定義は、対合歯に何らかの介入が必要になったこと(ただし、再セメント固定および咬合調整が単独で行われた例を除く)とした。観察期間は22.7±10.5ヵ月で、MZCの3年累積生存率は89.8%(95%CI 80.0～95.1%)、対合歯の同率は94.8%(95%CI 89.3～97.6%)となった。生存予測因子の候補として顎(上顎か下顎か)、歯種(小臼歯か大臼歯か)、歯髄の状態(生活か失活か)、を採り上げ、調整済みのCox比例ハザードモデルで検証した。その結果、MZC失敗と有意に関連している因子としては歯髄失活が同定された(ハザード比2.8e+9、P=0.01)。対合歯失敗の独立関連因子は対合歯自身の失活状態であった(ハザード比7.8、P=0.03)。単一臼歯MZC治療の成績は臨床的に許容できるものであったが、支台歯および対合歯が失活していることはそれぞれの治療失敗の潜在的な危険因子になっていると考えられた。

掲載種別：研究論文（学術雑誌）   出版者・発行元：Ceramics International  

Carbonate apatite (CO3Ap) artificial bone is fabricated in an aqueous solution using calcium carbonate as a precursor. CO3Ap has attracted attention because it demonstrates high osteoconductivity and can replace a damaged bone based on the bone remodeling process. This study aims to compare vaterite and calcite, which are metastable and stable polymorphs of calcium carbonate, respectively, as precursors. When the vaterite granules, which have higher solubility and consist of smaller crystals than calcite, prepared from calcium oxide granules were immersed in disodium hydrogen phosphate solution, the compositional transformation to CO3Ap was quicker than that of calcite. Based on the investigations on rabbit femurs, it was observed that the remodeling of CO3Ap to a new bone was faster when vaterite was used as a precursor compared to when calcite was used as a precursor. It is concluded that vaterite can be a better precursor than calcite for CO3Ap artificial bone fabrication.

DOI： 10.1016/j.ceramint.2022.05.336

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記述言語：日本語   出版者・発行元：一般社団法人 日本顎関節学会  

<p>オーラルアプライアンス（OA）は，顎関節症（TMD）および睡眠時ブラキシズム（SB）の治療に広く用いられているが，そのエビデンスは不十分である。そこで本研究では，ランダム化比較試験によりOAの治療効果を調査し，TMDとSBの相互関係を調べることを目的とした。九州大学病院を受診したTMD患者のうち，咀嚼筋痛およびSBを有する者16名を対象として，OA装着群と非装着群（各8名）に無作為割付を行った。各群において6週間にわたり咀嚼筋痛の程度，口腔関連QoL（Oral Health Impact Profile-49，OHIP-49），SB（携帯型筋電図）の記録を行い，比較検討した。また，治療効果に関連する因子とそれらの関与程度を調査するため，心理学的因子とダイアリーの記録を行った。咀嚼筋痛に関して，VASによる痛みの主観的評価では群間に有意差は認められなかったが，筋圧痛スコアおよびOHIP-49スコアにおいてはOA装着群のほうが有意に改善していた。また，SBはOA装着直後において有意に減少したが，1，4，6週後には差はみられなかった。SBと咀嚼筋痛との間に相関関係は認められなかった。OA治療は，咀嚼筋痛の緩和に有効であること，また1週間程度ではあるがSBの減弱にも効果があることが明らかとなった。</p>

DOI： 10.11246/gakukansetsu.34.38

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Pharmaceuticals  

Medication-related osteonecrosis of the jaw (MRONJ) is an intractable disease that is typically observed in patients with osteoporosis or tumors that have been treated with either bisphosphonate (BP) or antiangiogenic medicine. The mechanism of MRONJ pathogenesis remains unclear, and no effective definitive treatment modalities have been reported to date. Previous reports have indicated that a single injection of benidipine, an antihypertensive calcium channel blocker, in the vicinity of a tooth extraction socket promotes wound healing in healthy rats. The present study was conducted to elucidate the possibility of using benidipine to promote the healing of MRONJ-like lesions. In this study, benidipine was administered near the site of MRONJ symptom onset in a model rat, which was then sacrificed two weeks after benidipine injection, and analyzed using histological sections and CT images. The analysis showed that in the benidipine groups, necrotic bone was reduced, and soft tissue continuity was recovered. Furthermore, the distance between epithelial edges, length of necrotic bone exposed in the oral cavity, necrotic bone area, and necrotic bone ratio were significantly smaller in the benidipine group. These results suggest that a single injection of benidipine in the vicinity of MRONJ-like lesions can promote osteonecrotic extraction socket healing.

DOI： 10.3390/ph15081020

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：BMC Oral Health  

BACKGROUND: A novel type of implant (Straumann® BLX implant) has been developed for certain stability from the mechanical and biological aspects and is expected for the implant placement in atrophic maxilla with sinus floor elevation (SFE). PURPOSE: The aim of this study was to evaluate the primary stability in the implants with different macrodesigns in an SFE simulated model. Primary stabilities defined as maximum insertion torque (MIT) and implant stability quotient (ISQ) were compared between this novel type of implant and other types. MATERIALS AND METHODS: Five types of Straumann® 10 mm length implants (Standard Plus; SP, Tapered Effect; TE, Bone Level; BL, Bone Level Tapered; BLT and BLX) and two types of Straumann® 6 mm length implants (SP short, BLX short) were used in this study. Each implant was inserted through 5 mm-thick porcine iliac crest blocks (an SFE simulated model). Primary stability was evaluated by using MIT and ISQ. RESULTS: The mean value of MIT for BLX group showed significantly higher values than SP, BL (p < 0.01), and TE (p < 0.05) groups. The mean value of ISQ for BLX group was significantly higher than the other groups (p < 0.01). The mean value of MIT and ISQ for BLX and BLX short group were significantly higher than those for SP and SP short group (p < 0.01). CONCLUSIONS: In an SFE simulated ex vivo model, BLX group showed the highest values. These results suggest that implant selection can play a crucial role in the achievement of primary stability during SFE and simultaneous implant placement.

DOI： 10.1186/s12903-022-02345-5

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DOI： 10.14693/jdi.v29i2.1320

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記述言語：日本語   出版者・発行元：(一社)日本顎関節学会  

オーラルアプライアンス(OA)は,顎関節症(TMD)および睡眠時ブラキシズム(SB)の治療に広く用いられているが,そのエビデンスは不十分である。そこで本研究では,ランダム化比較試験によりOAの治療効果を調査し,TMDとSBの相互関係を調べることを目的とした。九州大学病院を受診したTMD患者のうち,咀嚼筋痛およびSBを有する者16名を対象として,OA装着群と非装着群(各8名)に無作為割付を行った。各群において6週間にわたり咀嚼筋痛の程度,口腔関連QoL(Oral Health Impact Profile-49,OHIP-49),SB(携帯型筋電図)の記録を行い,比較検討した。また,治療効果に関連する因子とそれらの関与程度を調査するため,心理学的因子とダイアリーの記録を行った。咀嚼筋痛に関して,VASによる痛みの主観的評価では群間に有意差は認められなかったが,筋圧痛スコアおよびOHIP-49スコアにおいてはOA装着群のほうが有意に改善していた。また,SBはOA装着直後において有意に減少したが,1,4,6週後には差はみられなかった。SBと咀嚼筋痛との間に相関関係は認められなかった。OA治療は,咀嚼筋痛の緩和に有効であること,また1週間程度ではあるがSBの減弱にも効果があることが明らかとなった。(著者抄録)

記述言語：英語   出版者・発行元：Healthcare (Switzerland)  

This retrospective study aimed to investigate the survival rate of implants from 5 to 10 years after the placement of implant-supported fixed dental prostheses (ISFDPs) and the management of implant loss in the elderly population. Elderly patients (≥65 years old) who had been treated with ISFDPs and followed up with for at least 5 years between October 2009 and March 2020 were enrolled. Patient profiles and implant-related data were extracted. The survival rate of implants up to 5 years as well as the 10-year cumulative survival rate were evaluated. The management of implant loss and prosthetic interventions were also investigated. In total, 195 patients (mean age: 70.1 ± 4.5 years old) and 687 implants (287 ISFDPs) were assessed. The 5-year survival rate was 99.0% and the 10-year cumulative survival rate was 98.1%. Seven of the eleven implants lost were lost due to peri-implantitis. Only three implants in two patients were placed after the loss of the implants; most were restored using non-invasive procedures. Two patients underwent a conversion from ISFDPs to removable prostheses. This study showed that high survival rates were observed in an elderly population with ISFDPs and that non-invasive procedures were often applied after the loss of an implant.

DOI： 10.3390/healthcare10071250

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記述言語：英語   出版者・発行元：Diagnostics  

Although the clinical assessment of enamel thickness is important, hardly any tools exist for accurate measurements. The purpose of this study was to verify the precision of enamel thickness measurements using swept-source optical coherence tomography (SS-OCT). Human extracted maxillary central and lateral incisors were used as specimens. Twenty-eight sites were measured in each specimen. The optical path length (OPL) at each measurement site was measured on the OCT images, and enamel thickness (e1) was calculated by dividing OPL by the mean refractive index of enamel, 1.63. The specimens were then sectioned, and a light microscope was used to measure enamel thickness (e2). e1 and e2 were then compared. Measurement errors between e1 and e2 for the central and lateral incisors were 0.04 (0.02; 0.06) mm and 0.04 (0.02; 0.07) mm [median value: (25%, 75% percentile)], respectively. No significant differences between measurement sites were noted for measurement errors between e1 and e2. These results demonstrate that OCT can be used for noninvasive, accurate measurements of enamel thickness.

DOI： 10.3390/diagnostics12071634

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記述言語：日本語   出版者・発行元：公益社団法人 日本口腔インプラント学会  

<p>本邦では口腔外科や補綴，歯周病のいずれかに軸足を置く歯科医師がインプラント治療を担当することが多いように思われる．そのため，特に自身がメインフィールドとする領域以外の治療において正確な難易度を判定する手法があれば，安心安全なインプラント治療を提供することができると考えられる．</p><p>現在，いくつかのインプラント治療難易度判定ツールが提案されているが，これまでに用いられてきた種々の分類法では難易度をうまく表現できない問題も存在する．たとえば，骨の質，量ともに問題なく咬合にも問題ない下顎臼歯部1歯中間欠損などはイージーケースといっても差し支えないと思われるが，一方で未経験者にとっては，骨をドリリングすること自体が難しく感じられるだろう．このように，ある症例が簡単か難しいかは，術者の感じ方や経験で大きく異なる．また，このような術者間で感じ方に差がある技術的難易度とは別個に，全身状態や治療部位，患者の個性に基づく難易度が存在する．これらの項目に問題がある場合にインプラント治療の成功率が低下することは，多くの場合質が高いエビデンスで裏づけされている．</p><p>日本口腔インプラント学会研究推進委員会では，Evidence-Based Difficulty Assessment Toolともいえる，術者の経験によらないインプラント治療の難易度分類を試みている．本稿ではその試案を提示する．</p>

DOI： 10.11237/jsoi.35.83

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Periodontology  

BACKGROUND: Refractory jaw osteonecrosis that occurs in osteoporotic or cancer patients treated with bisphosphonates is called medication-related osteonecrosis of the jaw but its underlying mechanism is unclear. Statins, therapeutic agents for dyslipidemia, lower blood low-density lipoprotein cholesterol. Fluvastatin promotes the healing of tooth extraction sockets and reduces the risk of developing medication-related osteonecrosis of the jaw-like lesions. We used a rat model to investigate whether injecting fluvastatin at extraction sites promoted the healing of medication-related osteonecrosis of the jaw-like lesions. METHODS: Upper first molars of rats administered zoledronate and dexamethasone for 2 weeks were extracted. Two weeks after tooth extraction, rats with medication-related osteonecrosis of the jaw-like lesions (bone exposure) were included in this study. A single injection of fluvastatin was administered in the vicinity of the medication-related osteonecrosis of the jaw-like onset site in rats. RESULTS: The distance between the edges of the epithelia, the length of the necrotic bone exposed toward the oral cavity, the area of the necrotic bone, and the necrotic bone ratio were significantly smaller in the fluvastatin-administered group compared with the saline group. A single application of fluvastatin near the site of medication-related osteonecrosis of the jaw onset showed a tendency to close the epithelium, reduce necrotic bone, and form new bone, even when symptoms had already developed. CONCLUSION: This study suggests that a single topical administration of fluvastatin may be a novel treatment for medication-related osteonecrosis of the jaw.

DOI： 10.1002/JPER.21-0294

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

本邦では口腔外科や補綴,歯周病のいずれかに軸足を置く歯科医師がインプラント治療を担当することが多いように思われる.そのため,特に自身がメインフィールドとする領域以外の治療において正確な難易度を判定する手法があれば,安心安全なインプラント治療を提供することができると考えられる.現在,いくつかのインプラント治療難易度判定ツールが提案されているが,これまでに用いられてきた種々の分類法では難易度をうまく表現できない問題も存在する.たとえば,骨の質,量ともに問題なく咬合にも問題ない下顎臼歯部1歯中間欠損などはイージーケースといっても差し支えないと思われるが,一方で未経験者にとっては,骨をドリリングすること自体が難しく感じられるだろう.このように,ある症例が簡単か難しいかは,術者の感じ方や経験で大きく異なる.また,このような術者間で感じ方に差がある技術的難易度とは別個に,全身状態や治療部位,患者の個性に基づく難易度が存在する.これらの項目に問題がある場合にインプラント治療の成功率が低下することは,多くの場合質が高いエビデンスで裏づけされている.日本口腔インプラント学会研究推進委員会では,Evidence-Based Difficulty Assessment Toolともいえる,術者の経験によらないインプラント治療の難易度分類を試みている.本稿ではその試案を提示する.(著者抄録)

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Healthcare (Switzerland)  

The clinical remount procedure, which involves remounting the dentures on an articulator with interocclusal records, can effectively reduce occlusal discrepancies. This procedure can be applied not only to new dentures but also to those already in service; however, research in this field is still scarce. This narrative review aims to establish a hypothetical mechanism and possible indications and contraindications for this technique as a basis for further research. Current studies have revealed a high prevalence of malocclusion in delivered dentures. Performing a clinical remount on these existing dentures would enhance the oral function of the denture wearer and would enable effective and accurate correction of the accumulated errors in the jaw relationship in a stable working environment. This technique should be performed if a patient has poor masticatory function or occlusion-related complaints. However, performing a clinical remount on dentures with an excessive anterior-posterior discrepancy between the centric relation and the maximal intercuspal position or on dentures with extremely low occlusal vertical dimension, is considered less effective. The clinical remount procedure remains an essential skill both for fabricating quality dentures and maintaining those already in service.

DOI： 10.3390/healthcare10061067

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記述言語：日本語   出版者・発行元：(公社)日本口腔インプラント学会  

本邦では口腔外科や補綴,歯周病のいずれかに軸足を置く歯科医師がインプラント治療を担当することが多いように思われる.そのため,特に自身がメインフィールドとする領域以外の治療において正確な難易度を判定する手法があれば,安心安全なインプラント治療を提供することができると考えられる.現在,いくつかのインプラント治療難易度判定ツールが提案されているが,これまでに用いられてきた種々の分類法では難易度をうまく表現できない問題も存在する.たとえば,骨の質,量ともに問題なく咬合にも問題ない下顎臼歯部1歯中間欠損などはイージーケースといっても差し支えないと思われるが,一方で未経験者にとっては,骨をドリリングすること自体が難しく感じられるだろう.このように,ある症例が簡単か難しいかは,術者の感じ方や経験で大きく異なる.また,このような術者間で感じ方に差がある技術的難易度とは別個に,全身状態や治療部位,患者の個性に基づく難易度が存在する.これらの項目に問題がある場合にインプラント治療の成功率が低下することは,多くの場合質が高いエビデンスで裏づけされている.日本口腔インプラント学会研究推進委員会では,Evidence-Based Difficulty Assessment Toolともいえる,術者の経験によらないインプラント治療の難易度分類を試みている.本稿ではその試案を提示する.(著者抄録)

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その他リンク： https://search-tp.jamas.or.jp/index.php?module=Default&action=Link&pub_year=2022&ichushi_jid=J02151&link_issn=&doc_id=20220801250004&doc_link_id=10.11237%2Fjsoi.35.83&url=https%3A%2F%2Fdoi.org%2F10.11237%2Fjsoi.35.83&type=J-STAGE&icon=https%3A%2F%2Fjk04.jamas.or.jp%2Ficon%2F00007_3.gif

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Endocrinology  

Menopausal women are susceptible to visceral obesity, which increases the risk of metabolic disorders. However, the mechanisms of menopause-induced visceral fat accumulation are not fully understood. Circulating levels of receptor activator of nuclear factor-kappa B (NF-κB) ligand (RANKL) are elevated in an animal model of menopause. RANKL, a multifunctional cytokine, activates the NF-κB pathway, which serves as a pivotal mediator of inflammatory responses. Here, we investigated whether RANKL-induced non-canonical NF-κB pathway activation induces inflammation and lipid accumulation in adipose tissues. RANKL induced Tnfa expression via the non-canonical NF-κB pathway in bone marrow cells. We therefore analyzed aly/aly mice, in which the non-canonical NF-κB pathway is not activated, owing to an inactive form of NF-κB-inducing kinase. A postmenopausal obesity model was generated by ovariectomy and subsequent high-fat and high-sucrose diet feeding. In aly/aly mice with postmenopausal obesity, serum RANKL levels were elevated, and hepatic lipid accumulation and adipocyte hypertrophy were suppressed, resulting in reduced macrophage infiltration and inflammatory cytokine mRNA expression in visceral adipose tissue. Furthermore, aly/aly mice showed protection from glucose intolerance and insulin resistance, which were observed in ovariectomized WT obese mice. These findings indicate that non-canonical NF-κB pathway activation via serum RANKL elevation contributes to postmenopausal obesity.

DOI： 10.1530/JOE-21-0424

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記述言語：英語   出版者・発行元：Regenerative Biomaterials  

The aim of this study was to investigate titanium membranes (TMs) layered between poly (lactic-co-glycolic acid) (PLGA) containing fluvastatin (FS) for use in guided bone regeneration. Membranes consisting of PLGA, FS-containing PLGA (PLGA-FS), TM layered between PLGA (TM-PLGA) and TM layered between FS-containing PLGA (TM-PLGA-FS) were prepared, and their mechanical and chemical properties were evaluated. The TM groups showed statistically significant differences, in terms of tensile strength and elastic modulus, when compared to the PLGA groups. The release of FS was demonstrated to be higher in the TM-PLGA-FS group than the PLGA-FS group after Day 14. The effect of membrane implantation on the calvaria of Wistar rats was measured using micro-computed tomography (micro-CT) and morphometrical analyses, as well as histological observations. At 4 weeks, the TM-PLGA-FS and TM-PLGA groups were found to have lower bone mineral density but higher bone formation, when compared to the control and PLGA groups. At 8 weeks, the use of TM-PLGA-FS membranes significantly enhanced bone formation in the calvaria model, compared to the other groups. These results suggest that a TM layered between PLGA containing FS potentially enhances bone formation, thus showing good potential as a GBR membrane.

DOI： 10.1093/rb/rbac061

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Healthcare (Switzerland)  

This case report describes a 70 year-old man with IVA lung cancer who required oral function rehabilitation by fabricating dentures with a simplified clinical remount technique. A pair of dentures were fabricated for a 70-year-old man with stage IVA lung cancer. Due to severe bimaxillary exostoses, the dentures could not properly extend and achieve a peripheral seal. The treatment philosophy was to stabilize the dentures and achieve proper function with optimized occlusion. The simplified Lauritzen clinical remount technique was performed at the time of denture delivery and 3 months later. After the second clinical remount procedure, the patient was able to eat meals with the dentures and maintained in a stable condition. Compared with the original technique, the simplified Lauritzen clinical remount omits the facebow transfer and keeps the condylar guidance setting and the Bennett angle unchanged during the adjustment. The prostheses are mounted to a type 3, non-arcon type articulator with anterior stop screws attached to the bilateral condylar parts. With the aid of anterior stop screws, the eccentric movement of dentures can be differentiated on a millimeter scale and balanced easily. It is effective to use occlusal-optimized dentures and the clinical remount technique, especially in difficult cases.

DOI： 10.3390/healthcare10040682

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: Low bone quantity and quality are serious problems that affect the prognosis of implants in the cosmetic field. Therefore, artificial bone substitutes are frequently used. However, whether there is a difference in the effect of either bone substitute on soft tissue healing is unclear given their greatly different absorbability. In this study, we used hydroxyapatite (HAp) and carbonate apatite (CO3Ap) as bone substitutes to analyze the epithelial and connective tissue healing after tooth extraction. METHODS: In vitro, oral mucosa-derived epithelial cells (OECs) collected from 4-day-old Wistar rats were seeded on HAp or CO3Ap and evaluated for adhesion, proliferation, migration, apoptosis, and morphology. Fibroblasts (FBs) were also analyzed for their ability to express collagen. In vivo, the extraction of maxillary right first (M1) and second molars (M2) of 6-week-old male Wistar rats was performed, followed by insertion of HAp or CO3Ap granules into the M1 and M2 sites. The oral mucosal healing process was then evaluated histochemically after 7 and 14 days. RESULTS: In vitro, high collagen expression by FBs in the CO3Ap group was observed and the surface analysis showed spreading of the FBs on the CO3Ap surface. However, the activity of OECs was suppressed on CO3Ap. Two weeks after CO3Ap implantation, soft tissue healing was observed, and recovery of the connective tissue was observed on the remaining CO3Ap. CONCLUSIONS: Our results suggest that the formation of soft tissues, including connective tissue, was promoted by CO3Ap in the extraction socket within a short period.

DOI： 10.1186/s40729-022-00408-4

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記述言語：日本語   出版者・発行元：(公財)8020推進財団  

インプラント治療後の残存歯および口腔関連QOLを他の歯科補綴治療との比較から明らかにすることを目的に、過去にインプラント義歯(IP)、ブリッジ(BR)、床義歯(RPD)治療前後に口腔関連QOL評価を受けた患者105名(IP群58名、BR群27名、RPD群20名)を対象に、6年経過後の追跡調査時における対象補綴装置の6年累積生存率、残存歯数、および口腔関連QOLを評価した。その結果、6年累積生存率はIP群94.7%、BR群77.4%、RPD群33.3%で、IP群は他の2群に比べ有意に高かった。追跡調査時の残存歯数については、IP群がRPD群に比べ有意に多かった。また、口腔関連QOLについては、IP群では治療開始前後、および治療前・追跡調査時のいずれにおいても有意に高くなっていたのに対し、他の2群ではいずれも有意差は認めなかった。

J-GLOBAL

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記述言語：日本語   出版者・発行元：(公財)8020推進財団  

インプラント治療後の残存歯および口腔関連QOLを他の歯科補綴治療との比較から明らかにすることを目的に、過去にインプラント義歯(IP)、ブリッジ(BR)、床義歯(RPD)治療前後に口腔関連QOL評価を受けた患者105名(IP群58名、BR群27名、RPD群20名)を対象に、6年経過後の追跡調査時における対象補綴装置の6年累積生存率、残存歯数、および口腔関連QOLを評価した。その結果、6年累積生存率はIP群94.7%、BR群77.4%、RPD群33.3%で、IP群は他の2群に比べ有意に高かった。追跡調査時の残存歯数については、IP群がRPD群に比べ有意に多かった。また、口腔関連QOLについては、IP群では治療開始前後、および治療前・追跡調査時のいずれにおいても有意に高くなっていたのに対し、他の2群ではいずれも有意差は認めなかった。

記述言語：英語   出版者・発行元：日本大学歯学部  

Purpose: The purpose of this study was to evaluate the 3-year cumulative survival rates of posterior single monolithic zirconia crowns (MZCs) and their antagonists, and to analyze the influencing factors. Methods: The clinical outcomes of posterior single MZCs and their abutment teeth with antagonists, and the antagonists between April 2014 and September 2020 were evaluated retrospectively. The 3-year cumulative survival rates were calculated and associations between the survival time and predictor variables (“Jaw”, “Tooth”, and “Pulpal condition”) were also verified using Cox proportional hazards models and hazard ratios (HRs). Results: The 3-year cumulative survival rate of single MZCs was 89.8% (9 of 177 MZCs, 95% confidence interval (CI): 80.0-95.1%). Cox proportional hazards models showed non-vital teeth were significantly associated with failure (HR: 2.76e + 9, P = 0.012). The 3-year cumulative survival rate of antagonists was 94.8% (7 of 171 antagonists, 95% CI: 89.3-97.6%). Non-vital antagonists were also identified as an independent predictor for failure in Cox proportional hazards models (HR: 7.83, P = 0.03). Conclusion: Although posterior single MZCs were clinically acceptable, non-vital pulpal condition could be a potential risk factor for failures in the abutment and antagonist teeth of MZCs.

DOI： 10.2334/josnusd.22-0221

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記述言語：日本語   出版者・発行元：公益社団法人 日本補綴歯科学会  

<p>　公益社団法人日本補綴歯科学会（JPS）は学術大会を開催し，また機関誌であるJournal of Prosthodontic Research（JPR）を発行して学会員の研究活動を広く公開している．これらの学会発表，あるいはJPR掲載論文を欧米の補綴歯科関連学会における発表および機関誌掲載論文と比較すると，バイオロジー研究や材料学的研究が多い等のJPS/JPR独自の特徴が見られる．また，JPRは補綴歯科関連国際誌のなかでも最も高いインパクトファクターを有しているが，他の指標と合わせて雑誌を評価すると，投稿者の国際的広がりや，掲載論文の国際的インパクトの点において改善の余地があると感じられる．</p>

DOI： 10.2186/ajps.14.137

CiNii Research

記述言語：日本語   出版者・発行元：公益社団法人 日本補綴歯科学会  

<p>　比較的少数歯の中間欠損症例で，ブリッジあるいはパーシャルデンチャーのどちらでも欠損補綴が可能であるような場合，最終補綴装置の選択に迷うことも少なくない．機能性，審美性，清掃性を備え，かつ長期的な使用に耐えうる補綴装置を製作するためには，比較的シンプルな症例であっても様々なことを考慮して選択・設計を行う必要がある．本稿では「少数歯の中間欠損症例における補綴装置の選択」をテーマとし，ブリッジまたはパーシャルデンチャー，あるいはその両方により対処した症例を供覧して補綴装置の選択理由や選択時の考慮事項について述べる．</p>

DOI： 10.2186/ajps.14.46

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）  

This study aimed to evaluate the influence of estrogen deficiency and mechanical loading on bone around osseointegrated dental implants in a rat jaw model. The maxillary right first molars of 36 rats were extracted. One week later, the rats were divided into an unloaded group and a loaded group; short head implants and long head implants were inserted respectively. Nine weeks after implantation, the rats were further subjected to ovariectomy (OVX) or sham surgery. All animals were euthanized 21 weeks after OVX. Micro-computed tomography, histological and histomorphometrical evaluation were undertaken. Systemic bone mineral density and bone volume fraction decreased in OVX groups compared with the sham controls. Histomorphometrical observation indicated that unloaded OVX group showed significantly damaged osseointegration and bone loss versus the loaded OVX group. Both the bone density (BD) inside the peri-implant grooves and the percentage of bone-to-implant contact (BIC) were lower in the OVX groups than in the sham-surgery groups, although mechanical loading increased the BIC and BD in the loaded OVX group compared with the unloaded OVX group. An increased number of positive cells for tartrate-resistant acid phosphatase was observed in the OVX groups versus the sham controls. The percentage of sclerostin-positive osteocytes was lower under loaded compared with unloaded conditions in both the OVX groups and the sham controls. In conclusion, estrogen deficiency could be a risk factor for the long-term stability of osseointegrated implants, while mechanical loading could attenuate the negative influence of estrogen deficiency on bone formation and osseointegration.

DOI： 10.1016/j.jmbbm.2021.104771

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The aim of this study was to evaluate clinical outcomes of staged sinus floor elevation (SFE) using novel low-crystalline carbonate apatite (CO3Ap) granules. Patients who needed SFE for implant placement were recruited into this clinical trial. A staged procedure (lateral window technique using CO3Ap granules, followed by implant placement after 7 ± 2 months) was employed in 13 patients. Bone-height increase and insertion torque values (ITVs) were assessed along with histological evaluation. The survival and success rates of 3-year functioning implants were also evaluated. Mean of bone-height increase after SFE using CO3Ap granules was 7.2 ± 2.5 mm and this increase allowed implant placement in all cases (17 implants). Mean of ITV was 25.1 ± 13.2 Ncm and primary stability was achieved successfully in all cases. Histological analyses revealed mature new bone formation (36.8 ± 17.3%) and residual CO3Ap granules (16.2 ± 10.1%) in the compartment after SFE. The survival and success rates after 3-year functional loading were 100% and no complications were found. These results clearly indicate the clinical usefulness of CO3Ap granules for SFE.

DOI： 10.3390/ma14195760

記述言語：英語   掲載種別：研究論文（学術雑誌）  

PURPOSE: To evaluate masticatory performance (MP), maximum occlusal force (MOF), maximum tongue pressure (MTP) and oral diadochokinesis (ODK) among community-dwelling elderly patients without posterior occlusal support. METHODS: This study enrolled community-dwelling elderly patients (≥65 years old) who belonged to Eichner A, B4, C1, C2, and C3. Each oral function was statistically compared among groups. Correlations between MP and other variables were examined in Eichner B4 and C patients. RESULTS: MP and MOF values in Eichner B4 and C patients were significantly lower than in Eichner A patients. There were significant differences in MTP values between Eichner "A and C2, C3", and "B4 and C2, C3". ODK in Eichner C patients showed significantly lower values compared to Eichner A patients in general. Although there were statistically significant correlations of MP with age, the number of remaining teeth and all oral functions were identified, and multiple regression analysis indicated that MOF and MTP were independently related to MP. CONCLUSION: Oral functions in Eichner B4 and C patients were lower compared to Eichner A patients. MP was significantly correlated with MOF and MTP in elderly patients without posterior occlusal support, suggesting the importance of rehabilitation of MOF and MTP in MP.

DOI： 10.2334/josnusd.21-0265

記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: Implant-supported removable partial dentures (ISRPD) are supported at the free-end region with implant retainers. As implant retainers prevent denture settlement and facilitate denture retention, this is intended to improve masticatory performance in comparison with that of conventional removable dentures. In the present study, we evaluated the effect of implant retainers at the free-end region of removable dentures on occlusal force and masticatory efficiency using a pressure-sensitive sheet, and measured glucose concentration in saliva after mastication with gummy candy. METHODS: In the present study, the occlusal force and masticatory efficiency of 13 subjects were measured in the following three conditions: without dentures (Condition 1), wearing dentures but not supported by implants (Condition 2), and wearing dentures supported by implants (ISRPD) (Condition 3). All data were statistically compared. RESULTS: Regarding the occlusal force, Condition 3 showed significantly higher scores than the other conditions; however, there were no significant differences between Conditions 1 and 2. Regarding the masticatory efficiency, Condition 3 showed significantly higher scores than Condition 2. CONCLUSIONS: With ISRPD, the occlusal force and masticatory efficiency were increased in comparison with those with conventional removable dentures.

DOI： 10.1186/s40729-021-00381-4

記述言語：英語   掲載種別：研究論文（学術雑誌）  

When taking the final impression for a three-unit fixed partial denture (FPD), the intaglio surface of the pontic of provisional restoration cannot be transferred accurately to that of definitive restoration. The intra- and extra-oral scanning (IEOS) technique, a method for accurately reproducing the submucosal morphology of the superstructure of an implant, has been reported using an intraoral scanner. In the present study, we evaluated the difference between the conventional impression method using impression material and the IEOS technique in reproducing the morphology of the surface of the pontic of a definitive FPD. There was a significant difference in the trueness of the intaglio surface morphology of the pontic between the conventional method and the IEOS technique; however, no significant difference in precision was observed. As a result, the intaglio surface of the pontic of the three-unit FPD could be transferred to definitive restorations more accurately with the IEOS technique than with the conventional method. These results suggest that the IEOS technique can duplicate the intaglio surface of the pontic more reproducibly to the definitive restorations compared with the conventional method.

DOI： 10.3390/ma14216489

記述言語：英語   掲載種別：研究論文（学術雑誌）  

This retrospective case-control study evaluated the prevalence of declined swallowing function and the association with oral functions and gender in community-dwelling elderly patients. Their profiles, the results of swallowing function (Eating Assessment Tool: EAT-10) and other oral functions (oral dryness, maximum occlusal force (MOF), tongue-lip motor function (oral diadochokinesis: ODK), maximum tongue pressure (MTP) and masticatory performance (MP)) were extracted for analyses. The patients were categorized into three groups according to EAT-10 score (Group 1: 0, Group 2: 1 and 2, Group 3: ≥3). In total, 242 patients were enrolled and 46 of them (19.0%) were categorized into declined swallowing function (Group 3). In two-group comparisons (Group 1, 2 versus Group 3), significant differences were identified in age and the number of remaining teeth, but they were not identified in three-group comparisons. The patients with declined swallowing function (Group 3) had significantly lower function in ODK and MTP. Multiple logistic regression analyses identified that declined swallowing function was independently associated with declined functions in ODK /ka/ (OR: 5.31, 95% CI: 1.03-27.23, p = 0.04) and in MTP (OR: 2.74, 95% CI: 1.12-6.66, p = 0.03). This study could confirm the critical role of tongue functions in swallowing in community-dwelling elderly patients.

DOI： 10.3390/jcm10153437

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The objective of this study was to investigate a bone graft substitute containing carbonate apatite (CO3Ap) to analyze bone replacement and the state of bone formation in vitro and in vivo compared with autogenous bone (AB) or control. An osteoclast precursor cell line was cultured with AB or CO3Ap, and morphological analysis using scanning electron microscopy and a tartrate-resistant acid phosphatase activity assay were performed. The right maxillary first and second molars of Wistar rats were extracted and compensated by AB or CO3Ap granules. Following implantation, the bone formation state was evaluated after 3, 5, 7, 14, and 28 days of surgery by micro-computed tomography and immunohistostaining. The osteoclast-like cell morphology was typical with many cell protrusions in the AB and CO3Ap groups. Additionally, the number of osteoclast-like cells formed in the culture increased in each group; however, there was no significant difference between the AB and CO3Ap groups. Five days after tooth extraction, osteoclasts were observed near CO3Ap. The bone thickness in the CO3Ap group was significantly increased than that in the control group and the bone formation in the CO3Ap group increased by the same level as that in the AB group. CO3Ap is gradually absorbed by osteoclasts in the extraction socket and is easily replaced by alveolar bone. The process of bone replacement by osteoclasts is similar to that of autologous bone. By observing the process of bone replacement in more detail, it may be possible to gain a better understanding of the bone formation and control the amount of bone after surgery.

DOI： 10.3390/ma14164457

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Fixed dentures (bridges) are often selected as a treatment option for a defective prosthesis. In this study, we assess the contact condition between the base of the pontic and oral mucosa, and examine the effect of prosthetic preparation and material biocompatibility. The molars were removed and replaced with experimental implants with a free-end type bridge superstructure after one week. In Experiment 1, we assessed different types of prosthetic pre-treatment: (1) the untreated control group (Con: mucosa recovering from the tooth extraction); (2) the laser irradiation group (Las: mucosa recovering after the damage caused by a CO2 laser); and (3) the tooth extraction group (Ext: mucosa recovering immediately after the teeth extraction). In Experiment 2, five materials (titanium, zirconia, porcelain, gold-platinum alloy, and self-curing resin) were placed at the base of the bridge pontic. Four weeks after the placement of the bridge, the mucosa adjacent to the pontic base was histologically analyzed. In Experiment 1, the Con and Las groups exhibited no formation of an epithelial sealing structure on the pontic base. In the Ext group, adherent epithelium was observed. In Experiment 2, the sealing properties at the pontic interface were superior for titanium and the zirconia compared with those made of porcelain or gold-platinum alloy. In the resin group, a clear delay in epithelial healing was observed.

DOI： 10.3390/ma14143997

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Mastication predominance in Kennedy class I (KC I) patients has not been well defined. This study aimed to investigate mastication predominance and masticatory performance in KC I patients, including the significance of remaining posterior teeth and removable partial-denture (RPD) treatment. KC I patients who had differences in the number of posterior teeth between left and right sides (D+) and KC I patients who had no differences (D-) were enrolled. Healthy dentate (HD) subjects were also registered as a positive control. Mastication predominance, defined by mastication predominance index (MPI; range 0-100%) calculated from electromyogram activities during voluntary chewing, and masticatory performance were evaluated at pre- and post-RPD treatment. Pre-MPI in KC I D+ was significantly higher than in HD. RPD treatment could significantly improve MPI and masticatory performance in both KC I groups. However, there were significant differences in masticatory performance between each KC I group and HD, regardless of RPD treatment. It was considered that the mastication predominance in KC I patients was affected by the difference in the number of remaining posterior teeth. RPD treatment could improve mastication predominance and masticatory performance in KC I patients, although the latter was not similar to HD group.

DOI： 10.3390/healthcare9060660

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The purpose of this study was to evaluate the effect of posterior occlusal support of natural teeth and artificial teeth on oral functions and standing motion. Patients who had been treated with removable prostheses were enrolled as the subjects. Their systemic conditions (body mass index (BMI) and skeletal muscle mass index (SMI)) were recorded. The subjects were classified into two groups according to a modified Eichner index: B1-3 (with posterior occlusal support) and B4C (without posterior occlusal support). Maximum occlusal force (MOF), masticatory performance (MP), and standing motion (sway and strength) were evaluated for cases with and without removable prostheses. There were no significant differences in BMI and SMI between the B1-3 group and the B4C group. The subjects with removable prostheses demonstrated significantly higher values in MOF, MP, and sway and strength than the subjects without removable prostheses. The comparison of oral functions between the B1-3 group and the B4C group revealed that the positive effect of posterior occlusal support of natural teeth and removable prostheses and the significant positive effects of posterior occlusal support on standing motion were partly observed in these comparisons. Posterior occlusal support of natural teeth and even of removable prostheses may contribute to the enhancement of oral functions and standing motion.

DOI： 10.3390/ijerph18136776

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Various materials, such as titanium, zirconia and platinum-gold (Pt-Au) alloy, have been utilized for dental implant trans-mucosal parts. However, biological understanding of soft tissue reaction toward these materials is limited. The aim of this study was to compare the response of cell lines and soft tissue to titanium, zirconia and Pt-Au substrata. The surface hydroxyl groups and protein adsorption capacities of the substrata were measured. Next, gingival epithelial-like cells (Sa3) and fibroblastic cells (NIH3T3) were cultured on the materials, and initial cell attachment was measured. Immuno-fluorescent staining of cell adhesion molecules and cytoskeletal proteins was also performed. In the rat model, experimental implants constructed from various materials were inserted into the maxillary tooth extraction socket and the soft tissue was examined histologically and immunohistochemically. No significant differences among the materials were observed regarding the amount of surface hydroxyl groups and protein adsorption capacity. Significantly fewer cells of Sa3 and NIH3T3 adhered to the Pt-Au alloy compared to the other materials. The expression of cell adhesion molecules and a well-developed cytoskeleton was observed, both Sa3 and NIH3T3 on each material. In an animal model, soft tissue with supracrestal tissue attachment was observed around each material. Laminin-5 immuno-reactivity was seen in epithelia on both titanium and zirconia, but only in the bottom of epithelia on Pt-Au alloy. In conclusion, both titanium and zirconia, but not Pt-Au alloy, displayed excellent cell adhesion properties.

DOI： 10.3390/jcm10112386

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The attrition of enamel when opposed by ceramics is of great concern. The purpose of this study was to evaluate enamel wear against high translucent zirconia (Zr), lithium disilicate (LD), gold (Au), and enamel (E) with different surface and contact conditions. The materials were divided into two groups: polished and ground (n=8 each). Two-body wear tests were performed against human enamel with vertical and horizontal, horizontal, and vertical repetitive movements as experiments 1 to 3 respectively. The surface roughness of all materials except Zr changed throughout the experiments. In experiment 1, Zr and Au showed less antagonist wear when polished than when ground. In experiment 2, polished groups showed less antagonist wear than ground groups in all materials. In experiment 3, Zr and LD exerted greater antagonist wear than E, regardless of Ra. These findings confirm the importance of polishing and occlusal adjustment of zirconia.

DOI： 10.4012/dmj.2020-190

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The purpose of this study was to investigate the effects of implant position and loading position on biomechanical behaviors using implant-supported removable partial denture (ISRPD) models in a simulated Kennedy class Ⅱ partially edentulous mandible. Three types of Kennedy class Ⅱ mandibular acrylic resin models (a conventional RPD without support by an implant-CRPD; models with an implant placed at first molar (#46)-MP-ISRPD- and second molar (#47)-DP-ISRPD) were used to measure vertical displacement of the RPD, mesio-distal displacement of the abutment tooth, and bending moment of the abutment tooth and implant under one-point loading. The variables at three respective loading points (#45, #46 and #47) were compared statistically. Vertical displacement was suppressed in ISRPDs compared to the CRPD, and significant effects were identified under loading at the implant position. The largest meiso-distal displacement was observed in MP-ISRPD under #47 loading. Bending moments of the abutment tooth and implant were significantly higher in MP-ISRPD than in DP-ISPRD. In MP-ISRPD, a higher bending moment of the abutment tooth under #45 and #47 loading was detected, although the bending moment in DP-ISRPD was almost zero. The results of this study suggested that MP-ISRPD shows the specific biomechanical behaviors, although DP-ISRPD might provide biomechanical benefits under all one-point loading conditions.

DOI： 10.3390/ma14092145

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background and objectives: In an aging society, the maintenance of the oral function of the elderly is of importance for the delay or prevention of frailty and long-term care. In the present study, we focused on the maximum tongue pressure (MTP) value and analyzed the relationship between MTP and age, occlusal status, or body mass index (BMI). Materials and Methods: This one-center observatory study was conducted using a cohort consisting of 205 community-dwelling outpatients over 65 years old. The MTP values of all subjects were measured using a commercially available tongue pressure measurement device and statistically analyzed. In addition, the correlation between MTP value and BMI was analyzed. Results: The MTP value decreased with age, especially in subjects classified as Eichner B and C. The difference in occlusal status did not show any statistically significant influence on MTP value. The correlation between BMI and MTP value was indicated in the tested groups other than an age of 65-74 and Eichner A groups. Conclusions: Although MTP value decreased with age, the difference in occlusal status did not have an impact on MTP value. The correlation between BMI and MTP value was not shown in the youngest group or a group with sufficient occlusal units. The results presented in the present study may imply that, even if MTP is low, younger age and/or better occlusal status compensate for the inferior MTP value in the cohort studied.

DOI： 10.3390/medicina56110623

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Currently, along with titanium (Ti), zirconia is widely used as an abutment material for dental implants because it makes it possible to avoid gingival discoloration; however, the epithelial sealing capability of zirconia remains unknown. The purpose of the present study is to elucidate the localization of integrin β4 subunit (Inβ4), one of the main proteins in the attachment structure between gingival junctional epithelial (JE) cells and substrata. Maxillary first molars were extracted from rats, and implants were placed with Ti or zirconia transgingival parts; then, the localization of Inβ4 was observed. Morphological and functional changes in rat oral epithelial cells (OECs) cultured on a culture dish (Dish) and Ti and zirconia plates were also evaluated with Inβ4 immunofluorescence histochemistry and Western blotting. After four weeks of implant placement, the morphology of the peri-implant epithelium (PIE) and the localization of Inβ4 around the Ti and zirconia transgingival parts were similar. However, both exhibited markedly shorter Inβ4-positive bands in the PIE than in the JE around natural teeth. Decreased expression levels of Inβ4 were observed in OECs cultured on Ti and zirconia plates compared with those cultured on Dish. In conclusion, although inferior to natural teeth, zirconia implants are thought to have epithelial sealing properties comparable to those of titanium.

DOI： 10.3390/jcm9103331

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Discontinuation of implant maintenance is the main risk factor for implant failure. The purpose of this study was to identify factors associated with previous discontinuation and resumption of maintenance among implant patients. A questionnaire survey was sent to 171 patients receiving implant maintenance at a university hospital; 169 patients responded. To assess the effect of job status, 26 patients (15.4%) with a history of maintenance discontinuation were classified as employed and nonemployed. The main reasons for previously discontinuing maintenance were work issues (in employed respondents) and dissatisfaction with treatment skill or chairside manner (in nonemployed respondents). The main reasons for resuming maintenance were those related to dental treatment (in employed respondents) and awareness of the importance of maintenance (in nonemployed respondents). There were significant differences in relation to job status in the reasons reported for discontinuing and resuming maintenance (both P < 0.05). The present findings suggest that oral health professionals should consider these factors when assisting patients in reducing the risk of implant failure.

DOI： 10.2334/josnusd.19-0318

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

OBJECTIVE: Mechanical plaque removal may alter the surface morphology of the gingival penetration part of the implant. We applied an air-powered abrasive system (AP), titanium curette (TC), stainless curette (SC), ultrasound scaler (US), and titanium brush (TB) which are commonly used to remove plaque, to titanium or zirconia and the changes in surface morphology and the epithelial attach against substrata. MATERIALS AND METHODS: (a) The morphological changes of titanium and zirconia after mechanical cleaning were assessed by scanning electron microscopy and a roughness analyser. (b) Oral epithelial cells of rats were inoculated on the surface of the materials after mechanical cleaning, and the adherence of epithelial cells was observed. (c) The maxillary first molars were extracted from the rats and replaced by experimental titanium or zirconia implants. The length of the immunoreactive laminin-332 band was observed at the implant-peri-implant epithelium interface. RESULTS: (a) The surface roughness increased in experimental groups except the AP group. (b) Among the experimental groups, the AP group showed the highest number of attached cells. (c) The length of the immunoreactive laminin-332 band was longer in the control group than those in all five experimental groups. Among the experimental groups, the AP group showed the longest band. CONCLUSION: All mechanical cleaning methods increased the surface roughness of the materials except AP. AP did not cause distinct implant surface alterations. Surface alteration caused by mechanical cleaning may evoke inferior for epithelial attachment and reduce resistance against foreign infiltration.

DOI： 10.1111/joor.12920

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Topographical modification of the dental implant surface is one of the main topics for the improvement of the material, however, the roughened surface has some risks for peri-implantitis. A hydrothermal treatment (HT) of titanium with calcium chloride solution was reported to improve osseointegration and soft tissue sealing without changing the surface topography; however, its mechanism is unclear. We herewith investigated the interaction between extracellular matrix (ECM) protein and HT titanium. Furthermore, we also clarified the bacterial interaction. We employed two kinds of HT, HT with water (DW-HT) and HT with calcium chloride solution (Ca-HT). As a result, the adsorptions of both laminin-332 and osteopontin onto the Ca-HT surface were enhanced. In contrast, the adsorption of albumin, which was reported to have no cell adhesion capacity, was not influenced by Ca-HT. Osteoblast adhesion onto Ca-HT was also enhanced. Although Ca-HT was reported to enhance both epithelial cell attachment strength and in vivo peri-implant epithelial bonding, the number of epithelial cell attachment was not increased even after HT. Ca-HT had no impact in the adhesion of Streptococcus gordonii. These results suggest that Ca-HT enhances cell adhesion onto titanium without increasing bacterial adhesion, and the improvement of ECM protein adsorption is supposed to contribute to cell adhesion.

DOI： 10.3390/jcm9082627

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Zirconia is widely employed as a material during dental implant work because of its superior esthetics. This study sought to evaluate the impact of titanium or zirconia implant abutments on epithelial attachments after ultrasonic cleaning. These implants were inserted into the extraction socket of rat maxillary first molars. Then, the length of the horseradish per-oxidase (HRP) reaction was measured. In addition, titanium and zirconia disks were cleaned using an ultrasonic scaler, surface morphology changes were observed, and the number of epithelial cell attachments to the surface was measured. Ultimately, the surfaces of the titanium disks were easier to damage than those of the zirconia ones. There was no difference in the number of epithelial cell attachments between the two materials with the ultrasonic cleaning. The length of the HRP reaction was shorter on the zirconia implant abutment surface than on the titanium one after mechanical cleaning. In conclusion, zirconia is harder than titanium and a better choice for use in the epithelial tissue attachment. Zirconia is more suitable as a material for implant abutments than titanium.

DOI： 10.2334/josnusd.19-0332

記述言語：英語   掲載種別：研究論文（学術雑誌）  

AIM: Previous studies on the association between intraoral conditions and mortality in community-dwelling older individuals reported that fewer present teeth (PT) are significant risk factors for mortality. However, how the number of PT relative to the number of functional teeth (FT), including both present and rehabilitated teeth, influences mortality has not been investigated fully. This study examined the impact of the number of FT on mortality among community-dwelling Japanese older adults. METHODS: This study was a retrospective, observational and population-based follow-up study, which examined 1188 older individuals who participated in an annual geriatric health examination from 2009 to 2015. The average follow-up period was 1697.0 ± 774.5 days. The primary outcome was all-cause mortality at follow-up. The numbers of PT and FT of each participant were counted during an oral examination. In addition, demographics, clinical variables, blood nutrient markers, physical functions and perceived masticatory function were measured. RESULTS: Kaplan-Meier analysis, followed by a log-rank test, revealed that fewer PT (P < 0.001) and FT (P = 0.002) were significantly associated with a reduced survival rate. Cox's proportional hazard analysis indicated that the number of FT, but not the number of PT, was a significant independent mortality risk factor after adjusting for demographics, clinical variables, nutrient markers and physical functioning (P = 0.036, hazard ratio: 2.089). CONCLUSIONS: Current results suggest that the number of FT more strongly predicts all-cause mortality than the number of PT among community-dwelling older adults. Further studies are necessary to consider the confounding of socioeconomic status and disability status. Geriatr Gerontol Int 2020; ••: ••-••.

DOI： 10.1111/ggi.13911

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The improvement of peri-implant epithelium (PIE) adhesion to titanium (Ti) may promote Ti dental implant stability. This study aims to investigate whether there is a positive effect of Ti hydrothermally treated (HT) with calcium chloride (CaCl₂), zinc chloride (ZnCl₂), and strontium chloride (SrCl₂) on promoting PIE sealing. We analyzed the response of a rat oral epithelial cell (OEC) culture and performed an in vivo study in which the maxillary right first molars of rats were extracted and replaced with calcium (Ca)-HT, zinc (Zn)-HT, strontium (Sr)-HT, or non-treated control (Cont) implants. The OEC adhesion on Ca-HT and Zn-HT Ti plates had a higher expression of adhesion proteins than cells on the Cont and Sr-HT Ti plates. Additionally, the implant PIE of the Ca-HT and Zn-HT groups revealed better expression of immunoreactive laminin-332 (Ln-322) at 2 weeks after implantation. The Ca-HT and Zn-HT groups also showed better attachment at the implant-PIE interface, which inhibited horseradish peroxidase penetration. These results demonstrated that the divalent cations of Ca (Ca²⁺) and Zn (Zn²⁺)-HT improve the integration of epithelium around the implant, which may facilitate the creation of a soft barrier around the implant to protect it from foreign body penetration.

DOI： 10.3390/MA13092038

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Medication-related osteonecrosis of the jaw (MRONJ) occurs in patients undergoing oral surgery while medicated with bisphosphonate, denosumab or anti-angiogenic agents. We employed a MRONJ-like rat model to investigate whether injecting fluvastatin at extraction sites prevents MRONJ-like lesion. A MRONJ-like model was created by treating rats with zoledronate and dexamethasone, extracting teeth, and immediately injecting fluvastatin at the extraction site. The experimental group comprised three subgroups treated with low (0.1 mg/kg; FS-L), medium (1.0 mg/kg; FS-M) and high concentrations (10 mg/kg; FS-H) of fluvastatin. Necrotic bone exposure was significantly lower in the FS-M (p = 0.028) and FS-H (p = 0.041) groups than in the MRONJ group. The distance between the edges of the epithelial surfaces was significantly shorter in the FS-M (p = 0.042) and FS-H (p = 0.041) groups. The area of necrotic bone and the necrotic bone ratio were significantly smaller in the FS-H group (p = 0.041 and p = 0.042 respectively). Bone volume fraction calculated on μ-CT images was significantly larger in the FS-H group than in the MRONJ group (p = 0.021). Our findings suggest that a single local injection of fluvastatin following tooth extraction can potentially reduce the chance of developing MRONJ-like lesion in rats.

DOI： 10.1038/s41598-020-61724-6

記述言語：日本語  

(公社)日本補綴歯科学会は、全国の歯学部学生を対象とした臨床技能コンペティション(課題:保険収載CAD/CAM冠を想定した支台歯形成、下顎右側第二小臼歯)を開催した。26校の代表者各1名が行った支台歯形成を審査し、上位6名の学生を選出した。これらの学生を対象としたオンサイトでの最終実技審査を行い、審査結果の公表および優秀者の表彰を同日に行った。審査は形成模型のデジタルスキャンデータを使用して算出されたテーパーと削除量を参考に、評価者による総括評価とした。事後アンケートでは肯定的な回答が寄せられ、特に参加学生にとって本企画が歯科技能向上に対する研鑽意欲を喚起するものであったことが明らかになった。(著者抄録)

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Stem cell therapy is an emerging treatment modality for various diseases. Because mesenchymal stem cells (MSCs) are known to accumulate at the site of damage, their possible clinical application has been investigated. MSCs are usually administered using intravenous injection, but this route carries a risk of pulmonary embolism. In contrast, topical injection of MSCs reportedly has an inferior therapeutic effect. We developed a remote administration method that uses collagen gel as a scaffold and investigated the effect of this scaffold on the retention of stemness, homing ability, and therapeutic effect using a mouse tooth extraction model. After verifying the retention of stemness of MSCs isolated from the bone marrow of donor mice in the scaffold, we administered MSCs subcutaneously into the back of the recipient mice with scaffold and observed the accumulation and the acceleration of healing of the extraction socket of the maxillary first molar. The MSCs cultured with scaffold retained stemness, the MSCs injected into back skin with scaffold successfully accumulated around the extraction socket, and socket healing was significantly enhanced. In conclusion, administration of MSCs with collagen scaffold at a remote site enhanced the lesion healing without the drawbacks of currently used administration methods.

DOI： 10.3390/app9224908

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: Much research has been invested in determining the effects of postoperative loading of implants and whether this loading contributes to implant failure, but the issue remains controversial. The present study aimed to elucidate whether cyclic lateral loading of an implant causes bone resorption or bone formation at various loading magnitudes, using a finite element method (FEM) and peri-implant morphologic and morphometric analyses. Methods: An FEM model was created using Digital Imaging and Communications in Medicine (DICOM) data of rabbit tibia. For the animal study, implants were inserted into rabbit tibia and, after osseointegration, were subjected to lateral cyclic loading of 20N, 40N or 60N. Results: Bone-implant contact was significantly higher in both 40N and 60N groups. Bone–abutment contact (BAC) was extraordinarily observed in all experimental groups. Bone height was higher than the implant platform level at higher levels of loading (60 N). Among the three experimental groups, those receiving 40 N loading had the highest bone height and BAC. Larger BAC values were observed on the compressive side than the tensile side. Conclusions: Peri-implant bone formation was enhanced with increased loading, with bone formation predominantly on the compressive side. BAC was highest in the 40 N group, implying existence of a loading threshold for peri-implant bone formation and resorption.

DOI： 10.1016/j.jpor.2018.10.009

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The purpose of this study was to evaluate the effects of an injectable composite made up of calcium sulfate (CAS), fluvastatin (FS), and atelocollagen on bone augmentation in rats. Porous structures and compressive strength of composites were evaluated. The cumulative release kinetics of FS were determined in vitro by a spectrophotometer. To observe bone regeneration in vivo, five different materials (normal saline; atelocollagen gel only; composite of CAS and atelocollagen; composite containing 0.5% FS; and composite containing 1.0% FS) were injected in extraction sockets and in the crania of rats. Microcomputed tomography and histological evaluation were performed after 2, 4, and 8 weeks of healing time. The composites had high porosity (greater than 55%). FS kept a slow and stable release for >30 days. In vivo results demonstrated that more new bone was formed in the FS groups compared with the other groups, and both bone mass and bone density had prominent increase in maxillae and crania. Resorption of the composite was also observed for cranial tissues. In conclusion, this composite can be applied percutaneously, without any incision. It has excellent properties with replaceability into bone and anabolic effects for bone formation, as well as a drug delivery system for bone formation.

DOI： 10.1021/acsbiomaterials.9b01045

記述言語：英語   掲載種別：研究論文（学術雑誌）  

PURPOSE: Much research has been invested in determining the effects of postoperative loading of implants and whether this loading contributes to implant failure, but the issue remains controversial. The present study aimed to elucidate whether cyclic lateral loading of an implant causes bone resorption or bone formation at various loading magnitudes, using a finite element method (FEM) and peri-implant morphologic and morphometric analyses. METHODS: An FEM model was created using Digital Imaging and Communications in Medicine (DICOM) data of rabbit tibia. For the animal study, implants were inserted into rabbit tibia and, after osseointegration, were subjected to lateral cyclic loading of 20N, 40N or 60N. RESULTS: Bone-implant contact was significantly higher in both 40N and 60N groups. Bone-abutment contact (BAC) was extraordinarily observed in all experimental groups. Bone height was higher than the implant platform level at higher levels of loading (60N). Among the three experimental groups, those receiving 40N loading had the highest bone height and BAC. Larger BAC values were observed on the compressive side than the tensile side. CONCLUSIONS: Peri-implant bone formation was enhanced with increased loading, with bone formation predominantly on the compressive side. BAC was highest in the 40N group, implying existence of a loading threshold for peri-implant bone formation and resorption.

DOI： 10.1016/j.jpor.2018.10.009

記述言語：英語   掲載種別：研究論文（学術雑誌）  

We previously reported that CaCl2 hydrothermal-treated (Ca-HT) titanium (Ti) implants induced a tight sealing at the interface between the implant and peri-implant epithelium (PIE) after implantation. However, it is not clear how long this improved epithelium sealing can be maintained. We subsequently investigated whether the positive effect of Ca-HT to promote sealing between the PIE and implant was sustained longer term. Maxillary molars were extracted from rats and replaced with either Ca-HT implants (Ca-HT group), distilled water-HT implants (DW-HT group) or non-treated implants (control group). After 16 weeks, the majority of implants in the Ca-HT group remained at the maxillary with no apical extension of the PIE. Conversely, half the number of control implants was lost following down-growth of the PIE. The effect of Ca-HT on migration and proliferation of rat oral epithelial cells (OECs) was also investigated. In OECs cultured on Ca-HT Ti plates, protein expression in relation to cell migration decreased, and proliferation was higher than other groups. Surface analysis indicated HT enhanced the formation of surface TiO2 layer without altering surface topography. Consequently, Ca-HT of Ti reduced PIE down-growth via tight epithelial attachment to the surface, which may enhance implant capability for a longer time post-implantation.

DOI： 10.3390/jcm8101560

記述言語：英語   掲載種別：研究論文（学術雑誌）  

We previously reported that CaCl2 hydrothermal-treated (Ca-HT) titanium (Ti) implants induced a tight sealing at the interface between the implant and peri-implant epithelium (PIE) after implantation. However, it is not clear how long this improved epithelium sealing can be maintained. We subsequently investigated whether the positive effect of Ca-HT to promote sealing between the PIE and implant was sustained longer term. Maxillary molars were extracted from rats and replaced with either Ca-HT implants (Ca-HT group), distilled water-HT implants (DW-HT group) or non-treated implants (control group). After 16 weeks, the majority of implants in the Ca-HT group remained at the maxillary with no apical extension of the PIE. Conversely, half the number of control implants was lost following down-growth of the PIE. The effect of Ca-HT on migration and proliferation of rat oral epithelial cells (OECs) was also investigated. In OECs cultured on Ca-HT Ti plates, protein expression in relation to cell migration decreased, and proliferation was higher than other groups. Surface analysis indicated HT enhanced the formation of surface TiO2 layer without altering surface topography. Consequently, Ca-HT of Ti reduced PIE down-growth via tight epithelial attachment to the surface, which may enhance implant capability for a longer time post-implantation.

DOI： 10.3390/jcm8101560

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The enhancement of oral epithelial adhesion to the trans-mucosal material of dental implants may improve their long-term stability. The aim of this study is to investigate whether hydrothermal treatment with distilled water (HT-DW) applied to a Ti-6Al-4V (Ti64) alloy could improve epithelial cellular attachment. We hypothesized that this treatment would enhance the adsorption of proteins and the adhesion of gingival epithelial GE1 cells. This treatment changed the surface crystal structure into an anatase type of titanium oxide without an apparent change of surface roughness or topography. Nitrogen was not detected on the HT-DW-treated Ti64, which indicates decontamination. HT-DW-treated Ti64 exhibited a hydrophilic surface with a less than 10° angle of water contact. Adsorption of laminin-332 to the HT-DW-treated Ti64 was significantly greater than that of the untreated Ti64 plates (64). The number of GE1 cells on the HT-DW-treated Ti64 at 1 and 3 days was significantly lower than that on 64; however, cell adhesion strength on HT-DW was greater, with a higher expression of integrin β4, compared with 64. This indicates that the HT-DW treatment of Ti64 improves the integration of GE1 cells, which might facilitate the development of a soft tissue barrier around the implant.

DOI： 10.3390/ma12172748

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The aims of implant treatment now involve not only restoration of mastication function, but also recovery of esthetics. Currently, zirconia is widely used as an esthetic material for implant abutment. Therefore, it is very important to understand the efficacy of zirconia for epithelial sealing as an implant material. We compared the effects of materials on the sealing of the peri-implant epithelium (PIE) to titanium (Ti) or zirconia (Zr) implants, for application to clinical work. Maxillary first molars were extracted from rats and replaced with Ti or Zr implants. The sealing of the PIE to the implants was evaluated with immunohistochemistry observation and HRP analysis. The morphological and functional changes in rat oral epithelial cells (OECs) cultured on Ti or Zr plates were also evaluated. After 4 weeks, the PIE on the Ti and Zr implants showed similar structures. The Zr implants appeared to form a weak epithelial seal at the tissue-implant interface, and exhibited markedly less adhesive structures than the Ti implants under electron microscopic observation. In the in vitro experiments, decreased expression levels of adhesion proteins were observed in OECs cultured on Zr plates compared with those cultured on Ti plates. In addition, the cell adherence on Zr plates was reduced, while the cell migration was low on Ti plates. Zr is a better choice for an esthetic implant material, but needs further improvement for integration with the epithelial wound healing process around a dental implant. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2019.

DOI： 10.1002/jbm.a.36651

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The development of effective methods to disinfect biofilms on dental materials is medically important. This study evaluated the bactericidal effects of peroxynitric acid (HOONO2; PNA) on biofilms formed on titanium surfaces. Streptococcus gordonii was cultured on either machined or rough titanium discs that were then used to evaluate the bactericidal effects of seven reagents, i.e., normal saline, benzalkonium chloride disinfectant solution, chlorhexidine digluconate solution, three concentration types of PNA, and inactivated PNA. Using low concentration of PNA, the bacterial count based on a CFU assay reached an undetectable level within 10 s; this bactericidal effect was the strongest observed for the seven tested reagents. Thus, PNA may be more useful than other disinfectants for sterilizing biofilms on titanium surfaces that have been contaminated with bacteria.

DOI： 10.4012/dmj.2018-274

記述言語：日本語  

記述言語：日本語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Osteocytes are thought to act as stress sensors, and are known to display a gap junction-mediated stress-transfer mechanism. To demonstrate the stress-related function of osteocytes, cells of an osteocyte-like cell line derived from murine long bone osteocyte Y4 (MLO-Y4) were cultivated in a three-dimensional culture and subjected to cyclic loading from a titanium plate. This application of physiological loading using a titanium plate significantly increased connexin 43 (Cx43) expression, the number of dead and apoptotic cells, and receptor activator of nuclear factor κB ligand expression. Furthermore, the conditioned medium from the loaded osteocytes induced alkaline phosphatase activity in bone marrow cell culture. In addition, we immunohistologically determined whether bone metabolism increased as a result of the occlusal force in the bone surrounding the titanium implants in a rat model. Increased Cx43 expression and apoptotic osteocytes were observed in the loading group as well as a significantly increased number of tartrate-resistant acid phosphatase-positive cells. These findings indicate that stress from the implant adversely affected the osteocytes, which may promote osteoclastic and osteoblastic cell formation around the implants.

DOI： 10.1002/jbm.a.36597

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Osteocytes are thought to act as stress sensors, and are known to display a gap junction-mediated stress-transfer mechanism. To demonstrate the stress-related function of osteocytes, cells of an osteocyte-like cell line derived from murine long bone osteocyte Y4 (MLO-Y4) were cultivated in a three-dimensional culture and subjected to cyclic loading from a titanium plate. This application of physiological loading using a titanium plate significantly increased connexin 43 (Cx43) expression, the number of dead and apoptotic cells, and receptor activator of nuclear factor κB ligand expression. Furthermore, the conditioned medium from the loaded osteocytes induced alkaline phosphatase activity in bone marrow cell culture. In addition, we immunohistologically determined whether bone metabolism increased as a result of the occlusal force in the bone surrounding the titanium implants in a rat model. Increased Cx43 expression and apoptotic osteocytes were observed in the loading group as well as a significantly increased number of tartrate-resistant acid phosphatase-positive cells. These findings indicate that stress from the implant adversely affected the osteocytes, which may promote osteoclastic and osteoblastic cell formation around the implants. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 815-827, 2019.

DOI： 10.1002/jbm.a.36597

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objective: A dihydropyridine-type calcium channel blocker, benidipine (BD), is extensively used in hypertension therapy. In vitro study reported BD promoting bone metabolism. We evaluated the effect of sustained release of BD-loaded poly(lactic-co-glycolic acid) (PLGA) microcarriers on the promotion of bone and gingival healing at an extraction socket in vivo. In addition, the effect of BD on osteoblasts, osteocytes, fibroblasts, and epithelial cells was evaluated in vitro. Approach: The maxillary first molar of rats was extracted. Next, PLGA microcarriers containing BD were directly injected into the gingivobuccal fold as a single dose. After injection, bone and soft-tissue healing was histologically evaluated. Effect of BD on proliferation, migration, and gene expression of gingival and bone cell was also examined in vitro. Results: After tooth extraction, BD significantly augmented bone volume and density, and also epithelial wound healing. During in vitro studies, BD promoted significant proliferation and migration of fibroblasts and epithelial cells. Real-time RT-PCR revealed that BD upregulated messenger RNA expression of Ahsg (alpha 2-HS glycoprotein) and Csf2 (colony-stimulating factor 2) in osteoblasts. Innovation: The prevention of bone and soft-tissue reduction associated with tooth extraction has been eagerly anticipated in the field of dentistry. This study first reported the effect of BD on extraction socket healing. Conclusion: A single dose of topically administered BD-loaded PLGA microcarriers promoted bone and soft-tissue healing at the extraction site of tooth.

DOI： 10.1089/wound.2018.0834

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The aims of implant treatment now involve not only restoration of mastication function, but also recovery of esthetics. Currently, zirconia is widely used as an esthetic material for implant abutment. Therefore, it is very important to understand the efficacy of zirconia for epithelial sealing as an implant material. We compared the effects of materials on the sealing of the peri-implant epithelium (PIE) to titanium (Ti) or zirconia (Zr) implants, for application to clinical work. Maxillary first molars were extracted from rats and replaced with Ti or Zr implants. The sealing of the PIE to the implants was evaluated with immunohistochemistry observation and HRP analysis. The morphological and functional changes in rat oral epithelial cells (OECs) cultured on Ti or Zr plates were also evaluated. After 4 weeks, the PIE on the Ti and Zr implants showed similar structures. The Zr implants appeared to form a weak epithelial seal at the tissue–implant interface, and exhibited markedly less adhesive structures than the Ti implants under electron microscopic observation. In the in vitro experiments, decreased expression levels of adhesion proteins were observed in OECs cultured on Zr plates compared with those cultured on Ti plates. In addition, the cell adherence on Zr plates was reduced, while the cell migration was low on Ti plates. Zr is a better choice for an esthetic implant material, but needs further improvement for integration with the epithelial wound healing process around a dental implant.

DOI： 10.1002/jbm.a.36651

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The purpose of this study was to evaluate the effects of a poly(lactic-co-glycolic acid) (PLGA) membrane containing fluvastatin on bone regeneration at bone defects in rat calvaria and tibia for possible use as a guided bone regeneration (GBR) membrane. PLGA and fluvastatin-containing PLGA (PLGA-fluvastatin) membranes were prepared and mechanical properties were evaluated. Standardized bony defects were created in rat calvaria and the right tibia, and covered with a PLGA or PLGA-fluvastatin membrane. Bone regeneration was evaluated using image analysis based on histologic examination. At 4 and 8 weeks after membrane implantation, the PLGA-fluvastatin group displayed enhanced new bone formation around the edge of the defect compared with the PLGA membrane group in the calvarial model. Thick bone regeneration was observed in tibia-defect sites in the PLGA-fluvastatin membrane group. These results suggest that the PLGA-containing fluvastatin membrane prepared in this study may potentially be used as a GBR membrane.

DOI： 10.1007/s10266-018-0376-z

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The development of effective methods to disinfect biofilms on dental materials is medically important. This study evaluated the bactericidal effects of peroxynitric acid (HOONO₂; PNA) on biofilms formed on titanium surfaces. Streptococcus gordonii was cultured on either machined or rough titanium discs that were then used to evaluate the bactericidal effects of seven reagents, i.e., normal saline, benzalkonium chloride disinfectant solution, chlorhexidine digluconate solution, three concentration types of PNA, and inactivated PNA. Using low concentration of PNA, the bacterial count based on a CFU assay reached an undetectable level within 10 s; this bactericidal effect was the strongest observed for the seven tested reagents. Thus, PNA may be more useful than other disinfectants for sterilizing biofilms on titanium surfaces that have been contaminated with bacteria.

DOI： 10.4012/dmj.2018-274

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Soft tissue barrier around a dental implant plays a crucial role in the success of dental implants because it protects underlying hard tissue structures. A number of surface alteration procedures of implants have been introduced to improve bone-implant contact, but there has been little research on the peri-implant soft tissue (PIS) seal. The present study focuses on the "biologic width" of epithelial and connective tissue seals around implants with various typical surface finishes by testing surfaces that have been machined (Ms), roughened by sandblasting and acid etching (Rs), treated hydrothermally with CaCl₂ (Cs), or anodized (As). Ms, Rs, and As techniques are commonly used to finish surfaces of commercially available dental implants. The Cs technique was reported to produce strong epithelial cell-titanium adhesion. For culture study, rat oral epithelial cells (OECs) and fibroblasts were cultured on Ms, Rs, Cs, and As titanium plates. There was less cell adherence of OECs and more collagen expression when cultured on Rs and As plates than when cultured on Ms and Cs plates. For the in vivo study, implants with Ms, Rs, Cs, and As surfaces were placed in the rats' oral cavity. Although the PIS structure was similar to that around natural teeth, a horseradish peroxide assay revealed that the sealing ability around the Ms and Rs implants was weaker than that around Cs implants. After 16 weeks, Rs implants exhibited peri-implant epithelial apical down-growth and had lost bone support. Thus, although a smooth surface (Ms and Cs) showed better epithelial attachment, rough surfaces (Rs and As) are more suitable for binding to the connective tissue. Strong epithelium-implant attachment seems to be a fundamental defense against foreign body penetration. Selecting suitable surfaces to ensure strong sealing is important for implant success.

DOI： 10.1021/acsbiomaterials.9b00499

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The enhancement of oral epithelial adhesion to the trans-mucosal material of dental implants may improve their long-term stability. The aim of this study is to investigate whether hydrothermal treatment with distilled water (HT-DW) applied to a Ti-6Al-4V (Ti64) alloy could improve epithelial cellular attachment. We hypothesized that this treatment would enhance the adsorption of proteins and the adhesion of gingival epithelial GE1 cells. This treatment changed the surface crystal structure into an anatase type of titanium oxide without an apparent change of surface roughness or topography. Nitrogen was not detected on the HT-DW-treated Ti64, which indicates decontamination. HT-DW-treated Ti64 exhibited a hydrophilic surface with a less than 10° angle of water contact. Adsorption of laminin-332 to the HT-DW-treated Ti64 was significantly greater than that of the untreated Ti64 plates (64). The number of GE1 cells on the HT-DW-treated Ti64 at 1 and 3 days was significantly lower than that on 64; however, cell adhesion strength on HT-DW was greater, with a higher expression of integrin β 4, compared with 64. This indicates that the HT-DW treatment of Ti64 improves the integration of GE1 cells, which might facilitate the development of a soft tissue barrier around the implant.

DOI： 10.3390/ma12172748

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The purpose of this study was to evaluate the effects of a poly(lactic-co-glycolic acid) (PLGA) membrane containing fluvastatin on bone regeneration at bone defects in rat calvaria and tibia for possible use as a guided bone regeneration (GBR) membrane. PLGA and fluvastatin-containing PLGA (PLGA–fluvastatin) membranes were prepared and mechanical properties were evaluated. Standardized bony defects were created in rat calvaria and the right tibia, and covered with a PLGA or PLGA–fluvastatin membrane. Bone regeneration was evaluated using image analysis based on histologic examination. At 4 and 8 weeks after membrane implantation, the PLGA–fluvastatin group displayed enhanced new bone formation around the edge of the defect compared with the PLGA membrane group in the calvarial model. Thick bone regeneration was observed in tibia-defect sites in the PLGA–fluvastatin membrane group. These results suggest that the PLGA-containing fluvastatin membrane prepared in this study may potentially be used as a GBR membrane.

DOI： 10.1007/s10266-018-0376-z

記述言語：日本語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.4103/0972-4052.244585

記述言語：日本語  

記述言語：英語  

A peptide that blocks the interaction of NF-B p65 subunit with Smad4 enhances BMP2-induced osteogenesis
Bone morphogenetic protein (BMP) potentiates bone formation through the Smad signaling pathway in vitro and in vivo. The transcription factor nuclear factor κB (NF-κB) suppresses BMP-induced osteoblast differentiation. Recently, we identified that the transactivation (TA) 2 domain of p65, a main subunit of NF-κB, interacts with the mad homology (MH) 1 domain of Smad4 to inhibit BMP signaling. Therefore, we further attempted to identify the interacting regions of these two molecules at the amino acid level. We identified a region that we term the Smad4-binding domain (SBD), an amino-terminal region of TA2 that associates with the MH1 domain of Smad4. Cell-permeable SBD peptide blocked the association of p65 with Smad4 and enhanced BMP2-induced osteoblast differentiation and mineralization without affecting the phosphorylation of Smad1/5 or the activation of NF-κB signaling. SBD peptide enhanced the binding of the BMP2-inudced phosphorylated Smad1/5 on the promoter region of inhibitor of DNA binding 1 (Id-1) compared with control peptide. Although SBD peptide did not affect BMP2-induced chondrogenesis during ectopic bone formation, the peptide enhanced BMP2-induced ectopic bone formation in subcortical bone. Thus, the SBD peptide is useful for enabling BMP2-induced bone regeneration without inhibiting NF-κB activity.

DOI： 10.1002/jcp.26571

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The purpose of this study was to evaluate the feasibility of using apatite blocks fabricated by a dissolution-precipitation reaction of preset gypsum, with or without statin, to enhance bone formation during socket healing after tooth extraction. Preset gypsum blocks were immersed in a Na₃PO₄ aqueous solution to make hydroxyapatite (HA) low crystalline and HA containing statin (HAFS), or in a mixed solution of Na₂HPO₄ and NaHCO₃ to make carbonate apatite (CO) and CO containing statin (COFS). The right mandibular incisors of four-week-old male Wistar rats were extracted and the sockets were filled with one of the bone substitutes or left untreated as a control (C). The animals were sacrificed at two and four weeks. Areas in the healing socket were evaluated by micro-computed tomography (micro-CT) and histological analyses. The bone volume, trabecular thickness, and trabecular separation were greatest in the COFS group, followed by the CO, HAFS, HA, and C groups. The bone mineral density of the COFS group was greater than that of the other groups when evaluated in the vertical plane. The results of this study suggest that COFS not only allowed, but also promoted, bone healing in the socket. This finding could be applicable for alveolar bone preservation after tooth extraction.

DOI： 10.3390/ma11071201

記述言語：英語   掲載種別：研究論文（学術雑誌）  

This study examined the influence of the time-dependent wettability of different surface topographies on initial cellular behavior. Titanium disks with smooth topography (SM) and three kinds of rough topography (sandblasted (SA), microtopography (M) and nanotopography (N)) were prepared. Time-dependent changes in surface wettability were observed in all surfaces as shown in previous studies. On SM surfaces, hydrophobic alteration influenced cell spreading and the activity of RhoA (a small GTPase protein of the Rho family), while no alterations were observed on rough surfaces except for the number of adherent cells. Serum adsorption could recover these functional deteriorations by hydrophobic alteration. These findings suggest that surface topography is a more potent regulator in initial cellular behaviors such as cell spreading and RhoA activation than surface wettability.

DOI： 10.4012/dmj.2017-334

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The purpose of this study was to evaluate the feasibility of using apatite blocks fabricated by a dissolution⁻precipitation reaction of preset gypsum, with or without statin, to enhance bone formation during socket healing after tooth extraction. Preset gypsum blocks were immersed in a Na₃PO₄ aqueous solution to make hydroxyapatite (HA) low crystalline and HA containing statin (HAFS), or in a mixed solution of Na₂HPO₄ and NaHCO₃ to make carbonate apatite (CO) and CO containing statin (COFS). The right mandibular incisors of four-week-old male Wistar rats were extracted and the sockets were filled with one of the bone substitutes or left untreated as a control (C). The animals were sacrificed at two and four weeks. Areas in the healing socket were evaluated by micro-computed tomography (micro-CT) and histological analyses. The bone volume, trabecular thickness, and trabecular separation were greatest in the COFS group, followed by the CO, HAFS, HA, and C groups. The bone mineral density of the COFS group was greater than that of the other groups when evaluated in the vertical plane. The results of this study suggest that COFS not only allowed, but also promoted, bone healing in the socket. This finding could be applicable for alveolar bone preservation after tooth extraction.

DOI： 10.3390/ma11071201

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: There are some spaces between abutment and implant body which can be a reservoir of toxic substance, and they can penetrate into subgingival space from microgap at the implant-abutment interface. This penetration may cause periimplantitis which is known to be one of the most important factors associated with late failure. In the present study, three kinds of abutment connection system, external parallel connection (EP), internal parallel connection (IP), and internal conical connection (CC), were studied from the viewpoint of microleakage from the gap between the implant and the abutment and in connection with the loosening of abutment screw. METHODS: We observed dye leakage from abutment screw hole to outside through microgap under the excessive compressive and tensile load and evaluated the anti-leakage characteristics of these connection systems. RESULTS: During the experiment, one abutment screw for EP and two screws for IP, out of seven samples in each group, were fractured. After the 2000 cycles of compressive tensile loadings, removal torque value (RTV) of abutment screw represented no statistical differences among three groups. Standard deviation was largest in the RTV of EP and smallest in that of CC. The results of microleakage of toluidine blue from implant-abutment connection indicated that microleakage generally increased as loading procedure progressed. The amount of microleakage was almost plateau at 2000 cycles in CC, but still increasing in other two groups. The value of microleakage greatly scattered in EP, but the deviation of that in CC is significantly smaller. At 500 cycles of loading, there were no significant differences in the amount of microleakage among the groups, but at 1000, 1500, and 2000 cycles of loading, the amount of microleakage in CC was significantly smaller than that in IP. Throughout the experiment, the amount of microleakage in EP was largest, but no statistical difference was indicated due to the high standard deviation. CONCLUSIONS: Within the limitation of the present study, CC was stable even after the loading in the RTV of abutment screw and it prevented microleakage from the microgap between the implant body and the abutment, among the three tested connections.

DOI： 10.1186/s40729-018-0121-y

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: Multipotent mesenchymal stem cells (MSCs) are used clinically in regenerative medicine. Our previous report showed systemically injected MSCs improved peri-implant sealing and accelerated tissue healing. However, the risks of systemic MSC administration, including lung embolism, must be considered; therefore, their local application must be assessed for clinical safety and efficacy. We investigated differences in treatment effect between local and systemic MSC application using a rat oral implantation model. METHODS: Rat bone marrow-derived MSCs were isolated and culture-expanded. The rat's right maxillary first molars were extracted and replaced with experimental titanium implants. After 24 h, MSCs (1 × 106/ml) were systemically or locally injected into recipient rats via the tail vein (systemic group) or buccal subcutaneous tissue (local group), respectively. Rats treated in the absence of MSCs were included as a control (control group). The maxillary epithelium was assessed histologically after 4 weeks to evaluate laminin-332 (Ln-332) distribution and horseradish peroxidase invasion, as indicators of peri-implant epithelium (PIE) formation and PIE sealing to the implant surface, respectively. The effect of MSCs on rat oral epithelial cell (OEC) morphology was determined by coculture. RESULTS: Systemic group MSCs accumulated early at the peri-implant mucosa, while local group MSCs were observed in various organs prior to later accumulation around the implant surface. PIE formation and Ln-332-positive staining at the implant interface were enhanced in the systemic group compared with the local and control groups. Furthermore, OEC adherence on implants was reduced in high-density compared with low-density MSC cocultures. CONCLUSIONS: Local MSC injection was more ineffective than systemic MSC injection at enhancing PIE sealing around titanium implants. Thus, although local MSC administration has a wide range of applications, further investigations are needed to understand the exact cellular and molecular mechanisms of this approach prior to clinical use.

DOI： 10.1186/s40729-017-0112-4

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Zirconia exhibits good tissue compatibility and nontoxicity, making it a widely used esthetic replacement material for implant abutments. To avoid abutment-fracture, the parts composed of zirconia with a bonded metal component connected to the implant can be used. The purpose of this study was to design titanium and zirconia components with high fracture resistance at the zirconia component’s edge line. Three edge line designs of the titanium base and zirconia sleeve were made: chamfer, shoulder, and back-taper. To assess the strength of the abutment design, static loads were applied vertically and 30 degrees from the vertical axis. A test of tensile strength was also performed after chewing simulation. Conventional zirconia components mounted on a chamfer-type titanium base showed significantly lower fracture resistance than shoulder and back-taper types. This study suggests that to improve the durability of zirconia abutments with a titanium base, a back-tapered edge design is recommended.

DOI： 10.4012/dmj.2017-022

記述言語：英語   掲載種別：研究論文（学術雑誌）  

This study examined the influence of the time-dependent wettability of different surface topographies on initial cellular behavior. Titanium disks with smooth topography (SM) and three kinds of rough topography (sandblasted (SA), microtopography (M) and nanotopography (N)) were prepared. Time-dependent changes in surface wettability were observed in all surfaces as shown in previous studies. On SM surfaces, hydrophobic alteration influenced cell spreading and the activity of RhoA (a small GTPase protein of the Rho family), while no alterations were observed on rough surfaces except for the number of adherent cells. Serum adsorption could recover these functional deteriorations by hydrophobic alteration. These findings suggest that surface topography is a more potent regulator in initial cellular behaviors such as cell spreading and RhoA activation than surface wettability.

DOI： 10.4012/dmj.2017-334

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/jcp.26571

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Statins are cholesterol-lowering drugs that inhibit 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, a rate-limiting enzyme of the mevalonate pathway. The anti-inflammatory effect of statins has been reported in recent years. The present study investigated therapeutic effects of the local administration of statin in osteoarthritis (OA). We assessed clinically used statins and selected fluvastatin for further experimentation, as it showed potent anabolic and anti-catabolic effects on human OA chondrocytes. To achieve controlled intra-articular administration of statin, we developed an intra-articular injectable statin using poly(lactic-co-glycolic acid) (PLGA) as a drug delivery system (DDS). The release profile of the statin was evaluated in vitro. Finally, therapeutic effects of fluvastatin-loaded PLGA microspheres (FLU-PLGA) were tested in a rabbit OA model. Rabbit knees were divided into four subgroups: group 1-A, PLGA-treated group; group 1-B, PLGA contralateral saline control group; group 2-A, FLU-PLGA-treated group; and group 2-B, FLU-PLGA contralateral saline control group. Histological analysis 5 weeks after intra-articular injection revealed that OARSI scores were lower in group 2-A. No significant differences in OARSI scores were observed between groups 1-A, 1-B, and 2-B. This study indicates that a single intra-articular injection of fluvastatin-loaded PLGA microspheres could be a novel therapeutic approach for treating patients with OA. (c) 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2465-2475, 2017.

DOI： 10.1002/jor.23562

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Statins are cholesterol-lowering drugs that inhibit 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, a rate-limiting enzyme of the mevalonate pathway. The anti-inflammatory effect of statins has been reported in recent years. The present study investigated therapeutic effects of the local administration of statin in osteoarthritis (OA). We assessed clinically used statins and selected fluvastatin for further experimentation, as it showed potent anabolic and anti-catabolic effects on human OA chondrocytes. To achieve controlled intra-articular administration of statin, we developed an intra-articular injectable statin using poly(lactic-co-glycolic acid) (PLGA) as a drug delivery system (DDS). The release profile of the statin was evaluated in vitro. Finally, therapeutic effects of fluvastatin-loaded PLGA microspheres (FLU-PLGA) were tested in a rabbit OA model. Rabbit knees were divided into four subgroups: group 1-A, PLGA-treated group; group 1-B, PLGA contralateral saline control group; group 2-A, FLU-PLGA-treated group; and group 2-B, FLU-PLGA contralateral saline control group. Histological analysis 5 weeks after intra-articular injection revealed that OARSI scores were lower in group 2-A. No significant differences in OARSI scores were observed between groups 1-A, 1-B, and 2-B. This study indicates that a single intra-articular injection of fluvastatin-loaded PLGA microspheres could be a novel therapeutic approach for treating patients with OA.

DOI： 10.1002/jor.23562

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The aim of this study was to evaluate the amount of bone formation beneath a defect area after treatment with titanium mesh membranes with different thicknesses and pore sizes alone or in combination with bone graft to induce bone formation during the early stage of healing time. The mandibular premolars were extracted bilaterally from three adult beagle dogs, and 8-mm-diameter bone defects were created on the buccal site of the premolar regions. Hydroxyapatite bone graft substitute was applied in the defect site unilaterally, and other site was left empty. Then, a novel micro-porous mesh (50 mu m in pore diameter) or commercially available macro-porous titanium mesh (1700 mu m in pore diameter) was placed on the defect and secured with screws. After 4 weeks, the mandibles were harvested, imaged using micro-computed tomography, and prepared for histological and morphometric evaluation. Higher new bone volumes (mm(3)), percentage of new bone volumes in the total defect volumes (bone ratio: %), and new bone area (mm(2)) through morphometric evaluation were found on the novel membranes with 50-mu m-diameter pores compared to the commercial titanium mesh. Moreover, experiment sites without bone graft were observed with higher new bone volume and bone ratio compared with sites with bone graft. However, bone mineral density of novel mesh was observed to be lower compared with other experimental sites. Under the experimental condition, the result of this study suggests that titanium meshes with 50-mu m-diameter pores were effective for guided bone regeneration in the early stage of healing.

DOI： 10.1007/s10266-017-0298-1

記述言語：日本語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

A number of finite element analyses (FEAs) for the dental implant were performed without regard for preload and with all interfaces ‘fixed-bonded’. The purpose of this study was comparing the stress distributions between the conventional FEA model with all contacting interfaces ‘fixed-bonded’ (bonded model) and the model with the interfaces of the components in ‘contact’ with friction simulated as a preloaded implant (contact model). We further verified the accuracy of the result of the FEA using model experiment. In the contact model, the stress was more widely distributed than in the bonded model. From the model study, the preload induced by screw tightening generated strain at the peri-implant bone, even before the application of external force. As a result, the bonded model could not reproduce the mechanical phenomena, whereas the contact model is considered to be appropriate for analysing mechanical problems.

DOI： 10.1080/10255842.2016.1236370

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: The aim of this study was to evaluate the effectiveness of a novel bone substitute material fabricated using a biodegradable polymer-calcium phosphate nanoparticle composite. Methods: Porous structured poly-l-lactic acid (PLLA) and hydroxyapatite (HA) nanoparticle composite, which was fabricated using solid-liquid phase separation and freeze-drying methods, was grafted into bone defects created in rat calvarium or tibia. Rats were killed 4 weeks after surgery, and histological analyses were performed to evaluate new bone formation. Results: Scanning electron microscopic observation showed the interconnecting pores within the material and the pore diameter was approximately 100 to 300 m. HA nanoparticles were observed to be embedded into the PLLA beams. In the calvarial implantation model, abundant blood vessels and fibroblastic cells were observed penetrating into pores, and in the tibia model, newly formed bone was present around and within the composite. Conclusions: The PLLA-HA nanoparticle composite bone substitute developed in this study showed biocompatibility, elasticity, and operability and thus has potential as a novel bone substitute.

記述言語：英語  

DOI： 10.1016/j.jpor.2016.01.004

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Mesenchymal stem cells (MSCs) have been isolated from a variety of tissues, including bone marrow, adipose, and mucosa. MSCs have the capacity for self-renewal and differentiation. Reports have been published on the systemic administration of MSCs leading to functional improvements by engraftment and differentiation, thus providing a new strategy to regenerate damaged tissues. Recently, it has become clear that MSCs possess immunomodulatory properties and can therefore be used to treat diseases. However, the therapeutic effect mechanisms of MSCs are yet to be determined. Here, we investigated these mechanisms using a medication-related osteonecrosis of the jaw (MRONJ)-like mouse model. Methods: To generate MRONJ-like characteristics, mice received intravenous zoledronate and dexamethasone two times a week. At 1 week after intravenous injection, maxillary first molars were extracted, and at 1 week after tooth extraction, MSCs were isolated from the bone marrow of the mice femurs and tibias. To compare "diseased MSCs" from MRONJ-like mice (d-MSCs) with "control MSCs" from untreated mice (c-MSCs), the isolated MSCs were analyzed by differentiation and colony-forming unit-fibroblast (CFU-F) assays and systemic transplantation of either d-MSCs or c-MSCs into MRONJ-like mice. Furthermore, we observed the exchange of cell contents among d-MSCs and c-MSCs during coculture with all combinations of each MSC type. Results: d-MSCs were inferior to c-MSCs in differentiation and CFU-F assays. Moreover, the d-MSC-treated group did not show earlier healing in MRONJ-like mice. In cocultures with any combination, MSC pairs formed cell-cell contacts and exchanged cell contents. Interestingly, the exchange among c-MSCs and d-MSCs was more frequently observed than other pairs, and d-MSCs were distinguishable from c-MSCs. Conclusions: The interaction of c-MSCs and d-MSCs, including exchange of cell contents, contributes to the treatment potential of d-MSCs. This cellular behavior might be one therapeutic mechanism used by MSCs for MRONJ.

DOI： 10.1186/s13287-016-0367-3

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Tissue Reaction to a Novel Bone Substitute Material Fabricated With Biodegradable Polymer-Calcium Phosphate Nanoparticle Composite.
PURPOSE: The aim of this study was to evaluate the effectiveness of a novel bone substitute material fabricated using a biodegradable polymer-calcium phosphate nanoparticle composite. METHODS: Porous structured poly-L-lactic acid (PLLA) and hydroxyapatite (HA) nanoparticle composite, which was fabricated using solid-liquid phase separation and freeze-drying methods, was grafted into bone defects created in rat calvarium or tibia. Rats were killed 4 weeks after surgery, and histological analyses were performed to evaluate new bone formation. RESULTS: Scanning electron microscopic observation showed the interconnecting pores within the material and the pore diameter was approximately 100 to 300 μm. HA nanoparticles were observed to be embedded into the PLLA beams. In the calvarial implantation model, abundant blood vessels and fibroblastic cells were observed penetrating into pores, and in the tibia model, newly formed bone was present around and within the composite. CONCLUSIONS: The PLLA-HA nanoparticle composite bone substitute developed in this study showed biocompatibility, elasticity, and operability and thus has potential as a novel bone substitute.

DOI： 10.1097/ID.0000000000000447

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Therapeutic interactions between mesenchymal stem cells for healing medication-related osteonecrosis of the jaw.
BACKGROUND: Mesenchymal stem cells (MSCs) have been isolated from a variety of tissues, including bone marrow, adipose, and mucosa. MSCs have the capacity for self-renewal and differentiation. Reports have been published on the systemic administration of MSCs leading to functional improvements by engraftment and differentiation, thus providing a new strategy to regenerate damaged tissues. Recently, it has become clear that MSCs possess immunomodulatory properties and can therefore be used to treat diseases. However, the therapeutic effect mechanisms of MSCs are yet to be determined. Here, we investigated these mechanisms using a medication-related osteonecrosis of the jaw (MRONJ)-like mouse model. METHODS: To generate MRONJ-like characteristics, mice received intravenous zoledronate and dexamethasone two times a week. At 1 week after intravenous injection, maxillary first molars were extracted, and at 1 week after tooth extraction, MSCs were isolated from the bone marrow of the mice femurs and tibias. To compare "diseased MSCs" from MRONJ-like mice (d-MSCs) with "control MSCs" from untreated mice (c-MSCs), the isolated MSCs were analyzed by differentiation and colony-forming unit-fibroblast (CFU-F) assays and systemic transplantation of either d-MSCs or c-MSCs into MRONJ-like mice. Furthermore, we observed the exchange of cell contents among d-MSCs and c-MSCs during coculture with all combinations of each MSC type. RESULTS: d-MSCs were inferior to c-MSCs in differentiation and CFU-F assays. Moreover, the d-MSC-treated group did not show earlier healing in MRONJ-like mice. In cocultures with any combination, MSC pairs formed cell-cell contacts and exchanged cell contents. Interestingly, the exchange among c-MSCs and d-MSCs was more frequently observed than other pairs, and d-MSCs were distinguishable from c-MSCs. CONCLUSIONS: The interaction of c-MSCs and d-MSCs, including exchange of cell contents, contributes to the treatment potential of d-MSCs. This cellular behavior might be one therapeutic mechanism used by MSCs for MRONJ.

DOI： 10.1186/s13287-016-0367-3

記述言語：日本語  

State-of-the-art of the Surface Modification of Oral Implants

DOI： 10.4139/sfj.67.297

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Soft tissue sealing around dental implants based on histological interpretation.
PURPOSE: The aim of this study was to provide an overview on the biology and soft tissue sealing around dental implants and teeth. STUDY SELECTION: This is a narrative review performed through scientific articles published between 1977 and 2014, indexed in MEDLINE and PubMed databases. The study selected articles that focused on epithelial sealing around dental implant or teeth with cell biology and histology of soft tissue. RESULTS: Implant therapy has been widely applied in dental rehabilitation for many years, with predictable long-term results. The longevity and functionality of dental implants is dependent on both osseointegration around the implant body and the establishment of a soft tissue barrier that protects the underlying hard tissue structures and the implant itself. The health and stability of the peri-implant mucosa also affects the esthetics of the implant. The healing and maintenance of the epithelial and connective tissues around implants are increasingly recognized as being fundamental to implant success. However, there has been little research into the function or formation of the soft tissue seal around dental implants, and the roles of this unique mucosal interface remain unclear. CONCLUSIONS: This narrative review explores the extent of the current knowledge of soft tissue barriers around implants from both a basic and clinical perspective, and aims to consolidate this knowledge and highlight the most pertinent questions relating to this area of research.

DOI： 10.1016/j.jpor.2015.07.001

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

インプラント治療が補綴歯科臨床の場で必要不可欠となった今日においても、未だ「インプラント支持固定性補綴装置に付与すべき咬合様式」のガイドラインまたは明確な基準は示されていない。本ポジションペーパーにおいては、その推奨されるべき一定の基準を示し、臨床上の指針として提案することを目的とした。本稿では、典型的な欠損形態である下顎大臼歯部欠損にインプラント支持補綴装置を装着した場合を想定している。口腔インプラントを適用した治療に関して経験豊富なエキスパートパネルを、(公社)日本補綴歯科学会会員から選出し、臨床の現場における事象を検証した結果として得られた意見を集積し、パネル会議で検討した。その結果、補綴装置の形態、咬合接触点の位置と数、側方運動時の咬合接触の有無、歯根膜の変位量の考慮、補綴装置咬合面の材料等に関する知見が得られ、推奨される一定の基準が示された。しかしながら、上記内容は明確な根拠に支持されるものではなく、治療効果と術後経過に関する研究が不十分であり、今後さらなる知見の集積と検証のもとに、ガイドラインを策定すべきである。(著者抄録)

DOI： 10.2186/ajps.8.1

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Additional Effects of Platelet-Rich Fibrin on Bone Regeneration in Sinus Augmentation With Deproteinized Bovine Bone Mineral: Preliminary Results.
PURPOSE: Platelet-rich fibrin (PRF) has been reported to contribute to bone regeneration; however, little is known about details with deproteinized bovine bone mineral (DBBM). This study aims to evaluate additional effects of PRF on bone regeneration in sinus augmentation with DBBM. MATERIALS AND METHODS: Sinus augmentations were made with DBBM/PRF mixture as lateral approach for 4 sinuses from 4 patients. Bone biopsies were obtained from posterior maxilla at the implant placements 7 or 10 months after sinus augmentations. Histological observations and histomorphometric analyses from augmented areas were performed. RESULTS: The new bone formation was found around the DBBMs with very good contact while surfaces of DBBMs were partly resorbed. Osteoclasts recognized the DBBMs for remodeling, followed by new bone running. The histomorphometric analyses revealed that mean percentages of newly formed bone were 31.7 ± 1.2%, 21.0 ± 1.0%, 38.0 ± 0.6%, and 47.0 ± 0.6%, respectively (mean 34.5 ± 5.7%). CONCLUSIONS: Additional effects of PRF could be found because of higher percentages of newly bone formation by DBBM/PRF mixture than those by DBBM individual in previous reports.

DOI： 10.1097/ID.0000000000000306

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Acceleration of hard and soft tissue healing in the oral cavity by a single transmucosal injection of fluvastatin-impregnated poly (lactic-co-glycolic acid) microspheres. An in vitro and rodent in vivo study.
Antihyperlipidemic drug statins reportedly promote both bone formation and soft tissue healing. We examined the effect of sustained-release, fluvastatin-impregnated poly(lactic-co-glycolic acid) (PLGA) microspheres on the promotion of bone and gingival healing at an extraction socket in vivo, and the effect of fluvastatin on epithelial cells and fibroblasts in vitro. The maxillary right first molar was extracted in rats, then one of the following was immediately injected, as a single dose, into the gingivobuccal fold: control (no administration), PLGA microspheres without a statin (active control), or PLGA microspheres containing 20 or 40 μg kg(-1) of fluvastatin. At days 1, 3, 7, 14, and 28 after injection, bone and soft tissue healing were histologically evaluated. Cell proliferation was measured under the effect of fluvastatin at dosages of 0, 0.01, 0.1, 1.0, 10, and 50 μM. Cell migration and morphology were observed at dosages of 0 and 0.1 μM. Following tooth extraction, the statin significantly enhanced bone volume and density, connective tissue volume, and epithelial wound healing. In the in vitro study, it promoted significant proliferation and migration of epithelial cells and fibroblasts. A single dose of topically administered fluvastatin-impregnated PLGA microspheres promoted bone and soft tissue healing at the extraction site.

DOI： 10.1088/1748-6041/11/1/015001

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1111/cid.12205

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Primary Stability of a Hybrid Implant Compared with Tapered and Cylindrical Implants in an Ex Vivo Model.
BACKGROUND: Hybrid implants are thought to offer good stability and bone-implant contact. PURPOSE: This study sought to evaluate the primary stability of a hybrid implant compared with tapered and cylindrical implants in an ex vivo model and compare undersized drilling with standard drilling in attaining primary stability. MATERIALS AND METHODS: Hybrid (Straumann® Bone Level; BL), tapered (Straumann® Tapered Effect; TE), and cylindrical (Straumann® Standard Plus; SP) implants were inserted into 15 mm-thick porcine iliac crest blocks using standard (corticocancellous or cancellous bone) or undersized (cancellous bone only) drilling (n = 7). Stability was evaluated using maximum insertion torque (MIT), implant stability quotient (ISQ), and push-out tests. RESULTS: The mean MIT for BL and TE was significantly higher than that for SP (p < 0.05). With standard drilling in corticocancellous bone, the mean ISQ for TE was significantly higher than that for SP (p < .05). The mean MIT, ISQ, and push-out test scores for BL, TE, and SP with standard drilling in corticocancellous bone were significantly higher than those with undersized or standard drilling in cancellous bone (p < .05). CONCLUSIONS: In this ex vivo model, the hybrid implant demonstrated promising primary stability compared with the cylindrical implant. The improved stability of the hybrid implant was especially evident in cancellous bone. The influence of the cortical layer should be recognized when selecting implants for primary stability.

DOI： 10.1111/cid.12205

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s10266-014-0151-8

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Effects of CaCl₂ hydrothermal treatment of titanium implant surfaces on early epithelial sealing.
Improvement of oral epithelial adhesion to titanium (Ti) may significantly enhance the efficacy of dental implants. We aimed to investigate whether calcium chloride (CaCl2) hydrothermally treated (HT) Ti could promote sealing of the peri-implant epithelium (PIE) around the implant. Right maxillary first molars were extracted from rats and replaced with either CaCl2-HT implants (Ca-HT group), distilled water-HT implants (DW-HT group), or untreated implants (Cont group). After 4 weeks, the implant-PIE interface of the Ca-HT group exhibited a band of immunoreactive laminin-332, similar to the tooth-junctional epithelium interface, which was absent in the Cont and DW-HT groups at the upper portion. We also investigated the effect of Ca-HT on the attachment of rat oral epithelial cells (OECs). OEC adherence onto Ca-HT Ti plates was stronger with higher expression levels of adhesion proteins compared with Cont and DW-HT groups. These results indicate that HT with CaCl2 improves the integration of soft tissue cells with the Ti implant at 4 weeks after implantation, which might facilitate the development of a soft tissue barrier around the implant.

DOI： 10.1016/j.colsurfb.2015.04.025

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: Platelet-rich fibrin (PRF) has been reported to contribute to bone regeneration; however, little is known about details with deproteinized bovine bone mineral (DBBM). This study aims to evaluate additional effects of PRF on bone regeneration in sinus augmentation with DBBM. Materials and Methods: Sinus augmentations were made with DBBM/PRF mixture as lateral approach for 4 sinuses from 4 patients. Bone biopsies were obtained from posterior maxilla at the implant placements 7 or 10 months after sinus augmentations. Histological observations and histomorphometric analyses from augmented areas were performed. Results: The new bone formation was found around the DBBMs with very good contact while surfaces of DBBMs were partly resorbed. Osteoclasts recognized the DBBMs for remodeling, followed by new bone running. The histomorphometric analyses revealed that mean percentages of newly formed bone were 31.7 ± 1.2%, 21.0 ± 1.0%, 38.0 ± 0.6%, and 47.0 ± 0.6%, respectively (mean 34.5 ± 5.7%). Conclusions: Additional effects of PRF could be found because of higher percentages of newly bone formation by DBBM/PRF mixture than those by DBBM individual in previous reports.

DOI： 10.1097/ID.0000000000000306

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Osteopetrosis (OP) is a rare condition characterized by skeletal sclerosis caused by dysfunctional osteoclasts. Though many reports have described severe infantile-malignant autosomal recessive OP, few have described the prosthetic management of adult OP. This report discusses the prosthetic treatment of adult OP. Although prosthodontists should try to reconstruct occlusal function as much as possible, a conservative prosthodontic approach may be a reasonable and recommended treatment option for minimizing the risk of further osteomyelitis and osteonecrosis.

DOI： 10.1016/j.prosdent.2014.04.007

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1111/cid.12043

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Relationship between the CT Value and Cortical Bone Thickness at Implant Recipient Sites and Primary Implant Stability with Comparison of Different Implant Types.
BACKGROUND: Studies have shown that bone quality at the implant recipient site can influence primary stability. PURPOSE: The aims of this study were to explore the quantitative estimation of the primary stability of implants preoperatively using CT values and to examine the effect of different implant designs with recommended socket preparation on primary stability. MATERIALS AND METHODS: Forty-four fresh porcine femoral heads were prepared. The bone surrounding implant sockets was preoperatively evaluated by helical CT. Forty-four implants (φ 4.3 × 10 mm), 22 straight and 22 tapered, were placed according to the manufacturer's instructions. The insertion torque value (ITV), implant stability quotient (ISQ), and removal torque value (RTV) were recorded as indicators of primary implant stability. RESULTS: Significant correlations and linear relationships were found between the CT value and ITV, ISQ, and RTV for both straight and tapered implants (Spearman's correlation coefficient, p < .001; linear regression analysis, p < .01). Tapered implants had a significantly higher ITV than straight implants (analysis of covariance, p < .01). CONCLUSIONS: Obtained results suggest that the primary stability of implants could be quantitatively estimated using the CT value preoperatively, indicating the CT value of bone surrounding an implant can contribute considerably to implant planning and design choice in clinical situations.

DOI： 10.1111/cid.12261

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Purpose: The objective of this study was to evaluate the optimal thickness and porosity of novel titanium mesh membranes to enhance bone augmentation, prevent soft tissue ingrowth, and prevent membrane exposure. Materials and Methods: Six types of novel titanium meshes with different thicknesses and pore sizes, along with three commercially available membranes, were used to cover surgically created calvarial defects in 6-week-old Sprague-Dawley rats. The animals were killed after 4 or 8 weeks. Microcomputed tomographic analyses were performed to analyze the three-dimensional bone volume and bone mineral density. Soft tissue ingrowth was also evaluated histologically and histomorphometrically. Results: The novel titanium membranes used in this study were as effective at augmenting bone in the rat calvarial defect model as the commercially available membranes. The greatest bone volume was observed on 100-mu m-thick membranes with larger pores, although these membranes promoted growth of bone with lower mineral density. Soft tissue ingrowth when 100-mu m membranes were used was increased at 4 weeks but decreased again by 8 weeks to a level not statistically significantly different from other membranes. Conclusion: Membrane thickness affects the total amount of new bone formation, and membrane porosity is an essential factor for guided bone regeneration, especially during the initial healing period, although the final bone volume obtained is essentially the same. Newly developed titanium mesh membranes of 100 mu m in thickness and with large pores appear to be optimal for guided bone regeneration.

DOI： 10.11607/jomi.3219

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： http://dx.doi.org/10.1016/j.jpor.2013.11.001

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Patients: Dental implant treatment in patients with complicated systemic disease has been discussed, especially in the context of achieving osseointegration. However, some patients with no pre-existing systemic disease develop it later, during their implant maintenance periods. Organ transplants, and the lifelong administration of immunosuppressants that follows, are also of relevance to post-implant oral health. Thus, strategies to maintain the health of pen-implant tissue in these patients should be considered. Here, we present the case of a patient receiving a living-donor lung transplant during her implant follow-up period. The condition of the lung is affected by that of the oral cavity, so the maintenance is of utmost importance. Throughout the follow-up period, we provided periodical professional maintenance care.
Discussion and conclusion: The patient experienced no complications, alterations in her radiographic findings, or worsening of periodontal indices, despite being extensively medicated with immunosuppressants, steroids and bisphosphonate. (C) 2013 Japan Prosthodontic Society. Published by Elsevier Ireland. All rights reserved.

DOI： 10.1016/j.jpor.2013.11.001

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Mesenchymal stem cells (MSCs) have potential to differentiate into multiple cell lineages. Recently, it was shown that MSCs also have anti-inflammatory and immunomodulatory functions. In this report, we investigated the regulatory function of MSCs in the development of inflammatory bone destruction in rats with adjuvant-induced arthritis (AA rats). MSCs were isolated from rat bone marrow tissues, expanded in the presence of basic FGF, and intraperitoneally injected into AA rats. MSC administration significantly suppressed inflammatory parameters: swelling score, swelling width, and thickness of hind paw. Radiographic evaluation indicated that MSC significantly suppressed bone destruction. Histological analysis showed that administration of MSCs markedly suppressed osteoclastogenesis in AA rats. To further delineate their effects on osteoclastogenesis, MSCs were added to in vitro bone marrow cultures undergoing osteoclastogenesis. MSCs significantly suppressed osteoclastogenesis in this system. Chemokine receptor expression in MSCs was assessed by RT-PCR, and a chemotactic assay was performed using a transwell culture system. MSCs showed significant chemotaxis to MIP-1 alpha (CCL3) and SDF-1 alpha (CXCL12), chemokines preferentially expressed in the area of inflammatory bone destruction. Furthermore, MSCs expressed IL-10 and osteoprotegerin, cytokines that suppress osteoclastogenesis. These data suggest that recruitment of MSC to the area of bone destruction in AA rats could suppress inflammatory bone destruction and raise the possibility that MSCs may have potential for the treatment of inflammatory bone destruction in arthritis.

DOI： 10.1038/labinvest.2013.152

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Fibroblast attachment onto novel titanium mesh membranes for guided bone regeneration.
Titanium mesh is used in orthopedic surgery as a barrier membrane, as it offers suitable characteristics, which allow mechanical support during the formation of new bone. An ideal membrane would facilitate cell attachment onto its surface, thereby helping to stabilize the blood clot and integrate the membrane into the tissue. However, currently available titanium mesh has millimeter-level pore sizes, which lead to soft tissue ingrowth through the pores. Therefore, the aim of this study was to investigate the fibroblast attachment and migration on different designs of novel titanium mesh with micrometer pore size for guided bone regeneration treatment. Six types of novel titanium mesh membrane and three groups of commercially available membranes were used in this study. Fibroblasts were isolated from 4-day-old green fluorescence protein rats and seeded onto membrane surfaces. At 24 h, the cells attached to the membrane surfaces were fixed and stained with DAPI. The blue-stained nuclei on membrane surfaces, and both upper and lower sides were counted. It was shown that different membrane materials, structure and design differ considerably in their capacity for cell attachment to the membrane surface. The novel membranes, especially mesh with 12 pores compared with mesh with multi-pores, allowed the fibroblast attachment on the membrane surface, but hindered the fibroblast migration through the pores into the lower side of the membrane, which is associated with the defect area in the clinical condition.

DOI： 10.1007/s10266-014-0151-8

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1371/journal.pone.0090681

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objectives: To investigate bacterial adhesion to various abutment materials. Material and methods: Thirty volunteers participated in this study. Resin splints were fabricated, and five types of disks were fabricated from pure titanium, gold-platinum alloy, zirconia, alumina, and hydroxyapatite with uniform surface roughness and attached to the buccal surface of each splint. After 4 days of use by the subjects, the plaque accumulated on the disk surfaces was analyzed. The bacterial community structure was evaluated using 16S rRNA gene profiling with terminal restriction fragment length polymorphism analysis. The total bacterial count on each disk was estimated using quantitative polymerase chain reaction. Results: Terminal restriction fragment length polymorphism profiles were more similar between tested materials than between subjects, suggesting that the bacterial community structures on the abutment material were influenced more by the individuals than by the type of material. However, the total number of bacteria attached to a disk was significantly different among five materials (P < 0.001, Brunner-Langer test for longitudinal data). Fewer bacteria were attached to the gold-platinum alloy than to the other materials. Conclusions: Gold-platinum alloy appears to be useful material for abutments when considering the accumulation of plaque. However, alternative properties of the abutment material, such as effects on soft tissue healing, should also be taken into consideration when choosing an abutment material. © 2012 John Wiley & Sons A/S.

DOI： 10.1111/j.1600-0501.2012.02574.x

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The role of phosphoinositide 3-kinase in adhesion of oral epithelial cells to titanium.
BACKGROUND: Oral epithelial cells (OECs) adhesion to titanium may improve the success rate of implant restoration. PURPOSE: We investigated the mechanism by which OECs adhere to titanium dental implants. MATERIALS AND METHODS: (1) After culturing rat OECs on titanium plates (Ti) or culture dishes in the presence or absence of a phosphoinositide 3-kinase (PI3K) activator or inhibitors and/or growth factors, and OEC morphology under these conditions were analyzed. (2) Right maxillary first molars were extracted and replaced with experimental implants. The rats were treated with or without growth factors. RESULTS: (1) Cell adherence was lower of OECs on Ti than in those on culture dishes, as were the levels of integrin β4 and the continuity of F-actin structures. After PI3K inhibition, markedly reducing adherence to both substrates. In contrast, PI3K activation with activator or insulin-like growth factor restored the OEC adherence and the expression of adhesion molecules on Ti to the levels seen in OECs cultured on dishes. Cell migration was inhibited by PI3K activation. (2) High expression of integrin β4 was observed in the peri-implant epithelia of PI3K-activated rats. CONCLUSION: These findings suggest that PI3K plays an important role in the adhesion of OECs to Ti.

DOI： 10.1016/j.archoralbio.2013.07.013

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The role of phosphoinositide 3-kinase in adhesion of oral epithelial cells to titanium.
BACKGROUND: Oral epithelial cells (OECs) adhesion to titanium may improve the success rate of implant restoration. PURPOSE: We investigated the mechanism by which OECs adhere to titanium dental implants. MATERIALS AND METHODS: (1) After culturing rat OECs on titanium plates (Ti) or culture dishes in the presence or absence of a phosphoinositide 3-kinase (PI3K) activator or inhibitors and/or growth factors, and OEC morphology under these conditions were analyzed. (2) Right maxillary first molars were extracted and replaced with experimental implants. The rats were treated with or without growth factors. RESULTS: (1) Cell adherence was lower of OECs on Ti than in those on culture dishes, as were the levels of integrin β4 and the continuity of F-actin structures. After PI3K inhibition, markedly reducing adherence to both substrates. In contrast, PI3K activation with activator or insulin-like growth factor restored the OEC adherence and the expression of adhesion molecules on Ti to the levels seen in OECs cultured on dishes. Cell migration was inhibited by PI3K activation. (2) High expression of integrin β4 was observed in the peri-implant epithelia of PI3K-activated rats. CONCLUSION: These findings suggest that PI3K plays an important role in the adhesion of OECs to Ti.

DOI： 10.1016/j.archoralbio.2013.07.013

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Promotive effect of insulin-like growth factor-1 for epithelial sealing to titanium implants
Improvement of oral epithelial adhesion to titanium (Ti) may significantly enhance the efficacy of dental implants. Here, we investigated whether insulin-like growth factor-1 (IGF-1) improved the sealing of the peri-implant epithelium (PIE) around the implant. Right maxillary first molars were extracted from rats and replaced with experimental implants. After 4 weeks of IGF-1 treatment, the implant-PIE interface exhibited a band of immunoreactive laminin-332 (Ln-5), similar to the tooth-junctional epithelium interface, that was partially absent in the untreated group. Immunoelectron microscopy showed a characteristic Ln-5-positive band including hemidesmosomes at both the apical and upper portions of the implant-PIE interface in the IGF-1-treated group. We also investigated the effects of IGF-1/PI3K inhibitors on the dynamics of rat oral epithelial cells (OECs) grown on Ti plates. In OECs cultured with IGF-1, adhesion protein expression increased, cell adherence to Ti plates was higher, and proliferation was faster, whereas migration and apoptosis were induced in the absence of IGF-1 or in the presence of both IGF-1 and a PI3K inhibitor. These data suggest that PI3K mediates the promotive effects of IGF-1, and that IGF-1 is effective at enhancing epithelial integration around Ti implants.

DOI： 10.1002/jbm.a.34608

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Promotive effect of insulin-like growth factor-1 for epithelial sealing to titanium implants
Improvement of oral epithelial adhesion to titanium (Ti) may significantly enhance the efficacy of dental implants. Here, we investigated whether insulin-like growth factor-1 (IGF-1) improved the sealing of the peri-implant epithelium (PIE) around the implant. Right maxillary first molars were extracted from rats and replaced with experimental implants. After 4 weeks of IGF-1 treatment, the implant-PIE interface exhibited a band of immunoreactive laminin-332 (Ln-5), similar to the tooth-junctional epithelium interface, that was partially absent in the untreated group. Immunoelectron microscopy showed a characteristic Ln-5-positive band including hemidesmosomes at both the apical and upper portions of the implant-PIE interface in the IGF-1-treated group. We also investigated the effects of IGF-1/PI3K inhibitors on the dynamics of rat oral epithelial cells (OECs) grown on Ti plates. In OECs cultured with IGF-1, adhesion protein expression increased, cell adherence to Ti plates was higher, and proliferation was faster, whereas migration and apoptosis were induced in the absence of IGF-1 or in the presence of both IGF-1 and a PI3K inhibitor. These data suggest that PI3K mediates the promotive effects of IGF-1, and that IGF-1 is effective at enhancing epithelial integration around Ti implants.

DOI： 10.1002/jbm.a.34608

記述言語：その他   掲載種別：研究論文（学術雑誌）  

Bone regeneration of tibial defects in rats with enzymatic hydrogelation of gelatin derivative and recombinant human platelet-derived growth factor-BB complex.

DOI： 10.11607/jomi.2861

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Tunneling nanotube formation is essential for the regulation of osteoclastogenesis.
Osteoclasts are the multinucleated giant cells formed by cell fusion of mononuclear osteoclast precursors. Despite the finding of several membrane proteins involving DC-STAMP as regulatory proteins required for fusion among osteoclast precursors, cellular and molecular events concerning this process are still ambiguous. Here we identified Tunneling Nanotubes (TNTs), long intercellular bridges with small diameters, as the essential cellular structure for intercellular communication among osteoclast precursors in prior to cell fusion. Formation of TNTs was highly associated with osteoclastogenesis and it was accompanied with the significant induction of the M-Sec gene, an essential gene for TNT formation. M-Sec gene expression was significantly upregulated by RANKL-treatment in osteoclast precursor cell line. Blockage of TNT formation by Latrunclin B or by M-Sec siRNA significantly suppressed osteoclastogenesis. We have detected the rapid intercellular transport of not only the membrane phospholipids labeled with DiI but also the DC-STAMP-GFP fusion protein through TNTs formed among osteoclast precursors during osteoclastogenesis. Transportation of such regulatory molecules through TNTs would be essential for the process of the specific cell fusion among osteoclast precursors.

DOI： 10.1002/jcb.24433

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Tunneling nanotube formation is essential for the regulation of osteoclastogenesis.
Osteoclasts are the multinucleated giant cells formed by cell fusion of mononuclear osteoclast precursors. Despite the finding of several membrane proteins involving DC-STAMP as regulatory proteins required for fusion among osteoclast precursors, cellular and molecular events concerning this process are still ambiguous. Here we identified Tunneling Nanotubes (TNTs), long intercellular bridges with small diameters, as the essential cellular structure for intercellular communication among osteoclast precursors in prior to cell fusion. Formation of TNTs was highly associated with osteoclastogenesis and it was accompanied with the significant induction of the M-Sec gene, an essential gene for TNT formation. M-Sec gene expression was significantly upregulated by RANKL-treatment in osteoclast precursor cell line. Blockage of TNT formation by Latrunclin B or by M-Sec siRNA significantly suppressed osteoclastogenesis. We have detected the rapid intercellular transport of not only the membrane phospholipids labeled with DiI but also the DC-STAMP-GFP fusion protein through TNTs formed among osteoclast precursors during osteoclastogenesis. Transportation of such regulatory molecules through TNTs would be essential for the process of the specific cell fusion among osteoclast precursors.

DOI： 10.1002/jcb.24433

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

In Vivo and In Vitro Studies of Epithelial Cell Behavior around Titanium Implants with Machined and Rough Surfaces
BACKGROUND: The surface roughness of a dental implant affects the epithelial wound healing process and may significantly enhance implant prognosis. PURPOSE: We explored the influence of surface roughness on peri-implant epithelium (PIE) sealing and down-growth by comparing machine-surfaced (Ms) and rough-surfaced (Rs) implants. MATERIALS AND METHODS: (1) Maxillary first molars were extracted from rats and replaced with Ms or Rs implants. (2) We also compared changes in the morphology of cultured rat oral epithelial cells (OECs) grown on Ms or Rs titanium (Ti) plates. RESULTS: (1) After 4 weeks, the PIE around Ms and Rs implants showed a similar structure to junctional epithelium (JE). At 16 weeks, Rs implants appeared to form a weak epithelial seal at the tissue-implant interface and exhibited markedly less PIE down-growth than Ms implants but was deeper than that observed in natural teeth. (2) We observed less expression of adhesion proteins in OECs cultured on Rs plates than in cells grown on Ms plates. Additionally, cell adherence, migration, and proliferation on Rs plates were lower, whereas apoptosis was reduced on Ms plates. CONCLUSION: Ms implants are a better choice for integration with an epithelial wound healing process.

DOI： 10.1111/cid.12043

記述言語：英語   掲載種別：研究論文（学術雑誌）  

In Vivo and In Vitro Studies of Epithelial Cell Behavior around Titanium Implants with Machined and Rough Surfaces
BACKGROUND: The surface roughness of a dental implant affects the epithelial wound healing process and may significantly enhance implant prognosis. PURPOSE: We explored the influence of surface roughness on peri-implant epithelium (PIE) sealing and down-growth by comparing machine-surfaced (Ms) and rough-surfaced (Rs) implants. MATERIALS AND METHODS: (1) Maxillary first molars were extracted from rats and replaced with Ms or Rs implants. (2) We also compared changes in the morphology of cultured rat oral epithelial cells (OECs) grown on Ms or Rs titanium (Ti) plates. RESULTS: (1) After 4 weeks, the PIE around Ms and Rs implants showed a similar structure to junctional epithelium (JE). At 16 weeks, Rs implants appeared to form a weak epithelial seal at the tissue-implant interface and exhibited markedly less PIE down-growth than Ms implants but was deeper than that observed in natural teeth. (2) We observed less expression of adhesion proteins in OECs cultured on Rs plates than in cells grown on Ms plates. Additionally, cell adherence, migration, and proliferation on Rs plates were lower, whereas apoptosis was reduced on Ms plates. CONCLUSION: Ms implants are a better choice for integration with an epithelial wound healing process.

DOI： 10.1111/cid.12043

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Current barrier membranes: titanium mesh and other membranes for guided bone regeneration in dental applications.
Research on guided bone regeneration (GBR) is still ongoing, with evidence mainly from preclinical studies. Various current barrier membranes should fulfill the main design criteria for GBR, such as biocompatibility, occlusivity, spaciousness, clinical manageability and the appropriate integration with the surrounding tissue. These GBR characteristics are required to provide the maximum membrane function and mechanical support to the tissue during bone formation. In this review, various commercially available, resorbable and non-resorbable membranes with different characteristics are discussed and summarized for their usefulness in preclinical studies. Membranes offer promising solutions in animal models; however, an ideal membrane has not been established yet for clinical applications. Every membrane type presents both advantages and disadvantages. Titanium mesh membranes offer superb mechanical properties for GBR treatment and its current efficacy in trials will be a focus in this review. A thorough understanding of the benefits and limitations inherent to various materials in specific clinical applications will be of great value and aid in the selection of an optimal membrane for GBR.

DOI： 10.1016/j.jpor.2012.12.001

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Effect of titanium surface calcium and magnesium on adhesive activity of epithelial-like cells and fibroblasts.
In the present study, we investigated the hydrothermal treatment of titanium with divalent cation solutions and its effect in promoting the adhesion of gingival epithelial cells and fibroblasts in vitro. Gingival keratinocyte-like Sa3 cells or fibroblastic NIH3T3 cells were cultured for 1 h on experimental titanium plates hydrothermally-treated with CaCl(2) (Ca) or MgCl(2) (Mg) solution, or distilled water (DW). The number and adhesive strengths of attached cells on the substrata were then analyzed. The number of Sa3 cells adhering to the Ca- and Mg-treated plates was significantly larger than in the DW group, but the strength of this adhesion did not differ significantly between groups. In contrast, NIH3T3 cell adhesion number and strength were increased in both the Ca and Mg groups compared to the DW group. Fluorescent microscopic observation indicated that, in all groups, Sa3 had identical expression levels of integrin β4 and development of actin filaments, whereas NIH3T3 cells in the Ca and Mg groups displayed much stronger punctate cytoplasmic signals for vinculin and more bundle-shaped actin filaments than cells in the DW group. As a result, it was indicated that the hydrothermal treatment of titanium with Ca or Mg solution improved the integration of soft tissue cells with the substrata, which may facilitate the development of a soft tissue barrier around the implant.

DOI： 10.1007/s13758-012-0027-9

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Effect of titanium surface calcium and magnesium on adhesive activity of epithelial-like cells and fibroblasts.
In the present study, we investigated the hydrothermal treatment of titanium with divalent cation solutions and its effect in promoting the adhesion of gingival epithelial cells and fibroblasts in vitro. Gingival keratinocyte-like Sa3 cells or fibroblastic NIH3T3 cells were cultured for 1 h on experimental titanium plates hydrothermally-treated with CaCl(2) (Ca) or MgCl(2) (Mg) solution, or distilled water (DW). The number and adhesive strengths of attached cells on the substrata were then analyzed. The number of Sa3 cells adhering to the Ca- and Mg-treated plates was significantly larger than in the DW group, but the strength of this adhesion did not differ significantly between groups. In contrast, NIH3T3 cell adhesion number and strength were increased in both the Ca and Mg groups compared to the DW group. Fluorescent microscopic observation indicated that, in all groups, Sa3 had identical expression levels of integrin β4 and development of actin filaments, whereas NIH3T3 cells in the Ca and Mg groups displayed much stronger punctate cytoplasmic signals for vinculin and more bundle-shaped actin filaments than cells in the DW group. As a result, it was indicated that the hydrothermal treatment of titanium with Ca or Mg solution improved the integration of soft tissue cells with the substrata, which may facilitate the development of a soft tissue barrier around the implant.

DOI： 10.1007/s13758-012-0027-9

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objectives The purpose of this study was to investigate the influence of the magnitude of immediate loading on peri-implant bone in an animal model of dental implantation. Material and methods Eight weeks after the extraction of maxillary and mandibular premolars, three implants were inserted bilaterally in the mandibles of six Beagle dogs. One implant was unloaded (UL) as a control, and two implants were loaded immediately with 10N (mild loading: ML) or 50N (excessive loading: EL) laterally using a cyclic loading device twice a week for 3weeks. Fluorescent bone markers were injected to examine bone formation around the implants. The animals were sacrificed 3weeks after implantation. Peri-implant osteogenesis was assessed by histomorphometric procedures, i.e., measuring bone-implant contact (BIC) and bone density (BD). Results The UL and ML groups had no peri-implant infection, and newly formed bone was observed over a wide area from the implant neck toward the tip, and in direct contact with the implant surface. In contrast, in the EL group, newly formed bone was rarely observed around the implant neck and there were signs of infection. Both BIC and BD in the ML group were significantly greater than those in the other groups. BIC and BD in the EL group were significantly lower than those in the other groups. Conclusion A suitable magnitude of load applied immediately after dental implantation promotes peri-implant osteogenesis.

DOI： 10.1111/j.1600-0501.2011.02305.x

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objectives The purpose of this study was to investigate the influence of the magnitude of immediate loading on peri-implant bone in an animal model of dental implantation. Material and methods Eight weeks after the extraction of maxillary and mandibular premolars, three implants were inserted bilaterally in the mandibles of six Beagle dogs. One implant was unloaded (UL) as a control, and two implants were loaded immediately with 10N (mild loading: ML) or 50N (excessive loading: EL) laterally using a cyclic loading device twice a week for 3weeks. Fluorescent bone markers were injected to examine bone formation around the implants. The animals were sacrificed 3weeks after implantation. Peri-implant osteogenesis was assessed by histomorphometric procedures, i.e., measuring bone-implant contact (BIC) and bone density (BD). Results The UL and ML groups had no peri-implant infection, and newly formed bone was observed over a wide area from the implant neck toward the tip, and in direct contact with the implant surface. In contrast, in the EL group, newly formed bone was rarely observed around the implant neck and there were signs of infection. Both BIC and BD in the ML group were significantly greater than those in the other groups. BIC and BD in the EL group were significantly lower than those in the other groups. Conclusion A suitable magnitude of load applied immediately after dental implantation promotes peri-implant osteogenesis.

DOI： 10.1111/j.1600-0501.2011.02305.x

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Relationship between the bone density estimated by cone-beam computed tomography and the primary stability of dental implants.
OBJECTIVES: The aims of this study were to objectively assess bone quality with density values obtained by cone-beam computed tomography (CBCT) and to determine the correlations between bone density and primary stability of dental implants. MATERIAL AND METHODS: Eighteen Straumann implants were inserted into 18 fresh femoral heads of swine. The bone densities of implant recipient sites were preoperatively determined by the density value using CBCT. The maximum insertion torque value of each implant was recorded using a digital torque meter. Resonance frequency, which represented a quantitative unit called the implant stability quotient (ISQ), was measured using an Osstell Mentor immediately after the implant placement. Spearman's correlation coefficient was calculated to evaluate the correlations among density values, insertion torques, and ISQs at implant placement. RESULTS: The density values ranged from 98 to 902. The mean density value, insertion torque, and ISQ were 591 ± 226, 13.4 ± 5.2 Ncm, and 67.1 ± 8.1, respectively. Statistically significant correlations were found between the density values and insertion torque (r(s) =0.796, P<0.001), density values and ISQ (r(s) =0.529, P=0.024), and insertion torque and ISQ (r(s) =0.758, P<0.001). CONCLUSIONS: The bone quality evaluated by specific CBCT showed a high correlation with the primary stability of the implants. Hence, preoperative density value estimations by CBCT may allow clinicians to predict implant stability. Whether the density values obtained by the CBCT device used in the present study could be applied to other devices requires further elucidation.

DOI： 10.1111/j.1600-0501.2011.02203.x

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The difference of fibroblast behavior on titanium substrata with different surface characteristics.
Connective tissue, one of the main components of peri-implant soft tissue, is key to the formation of the peri-implant mucosal seal and helping to prevent epithelial ingrowth. Rough surfaces (Rs), machined surfaces (Ms) or microgrooved surface (MG) are used in the neck area of commercially available titanium implants. In this paper, we aimed to evaluate the influence of surface topography of titanium substratum on connective tissue fibroblasts to gain a better understanding of this effect. Fibroblasts were cultured on titanium plates with Rs, Ms and MG. Adhesion cell number at day 3 was compared and protein distribution of both F-actin and vinculin was determined to observe cellular structure and adhesion. Cell adhesion strength was compared on each surface. At day 3, the number of fibroblasts attached on each substratum was in the order of MG ≈ Ms > Rs. Fibroblasts strongly expressed vinculin in the peripheral area on Ms and MG, and showed strong F-actin architecture. Decreased expression of vinculin and weaker continuity of F-actin were observed on Rs. Fibroblasts on MG were aligned along the grooves, with a significantly higher cell density, whereas cells on Ms and Rs had no clear orientation. The cell adhesion strength was significantly lower on Rs, and no significant difference was seen between MG and Ms. Both MG and Ms showed greater adhesion cell numbers and adhesion strength of fibroblasts when compared with Rs at day 3. The cell density on MG was greater than those on other substrata.

DOI： 10.1007/s10266-011-0029-y

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Relationship between the bone density estimated by cone-beam computed tomography and the primary stability of dental implants.
OBJECTIVES: The aims of this study were to objectively assess bone quality with density values obtained by cone-beam computed tomography (CBCT) and to determine the correlations between bone density and primary stability of dental implants. MATERIAL AND METHODS: Eighteen Straumann implants were inserted into 18 fresh femoral heads of swine. The bone densities of implant recipient sites were preoperatively determined by the density value using CBCT. The maximum insertion torque value of each implant was recorded using a digital torque meter. Resonance frequency, which represented a quantitative unit called the implant stability quotient (ISQ), was measured using an Osstell Mentor immediately after the implant placement. Spearman's correlation coefficient was calculated to evaluate the correlations among density values, insertion torques, and ISQs at implant placement. RESULTS: The density values ranged from 98 to 902. The mean density value, insertion torque, and ISQ were 591 ± 226, 13.4 ± 5.2 Ncm, and 67.1 ± 8.1, respectively. Statistically significant correlations were found between the density values and insertion torque (r(s) =0.796, P<0.001), density values and ISQ (r(s) =0.529, P=0.024), and insertion torque and ISQ (r(s) =0.758, P<0.001). CONCLUSIONS: The bone quality evaluated by specific CBCT showed a high correlation with the primary stability of the implants. Hence, preoperative density value estimations by CBCT may allow clinicians to predict implant stability. Whether the density values obtained by the CBCT device used in the present study could be applied to other devices requires further elucidation.

DOI： 10.1111/j.1600-0501.2011.02203.x

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The difference of fibroblast behavior on titanium substrata with different surface characteristics.
Connective tissue, one of the main components of peri-implant soft tissue, is key to the formation of the peri-implant mucosal seal and helping to prevent epithelial ingrowth. Rough surfaces (Rs), machined surfaces (Ms) or microgrooved surface (MG) are used in the neck area of commercially available titanium implants. In this paper, we aimed to evaluate the influence of surface topography of titanium substratum on connective tissue fibroblasts to gain a better understanding of this effect. Fibroblasts were cultured on titanium plates with Rs, Ms and MG. Adhesion cell number at day 3 was compared and protein distribution of both F-actin and vinculin was determined to observe cellular structure and adhesion. Cell adhesion strength was compared on each surface. At day 3, the number of fibroblasts attached on each substratum was in the order of MG ≈ Ms > Rs. Fibroblasts strongly expressed vinculin in the peripheral area on Ms and MG, and showed strong F-actin architecture. Decreased expression of vinculin and weaker continuity of F-actin were observed on Rs. Fibroblasts on MG were aligned along the grooves, with a significantly higher cell density, whereas cells on Ms and Rs had no clear orientation. The cell adhesion strength was significantly lower on Rs, and no significant difference was seen between MG and Ms. Both MG and Ms showed greater adhesion cell numbers and adhesion strength of fibroblasts when compared with Rs at day 3. The cell density on MG was greater than those on other substrata.

DOI： 10.1007/s10266-011-0029-y

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Evaluations of epithelial sealing and peri-implant epithelial down-growth around "step-type" implants.
OBJECTIVE: Implant designs that can stimulate and integrate with an epithelial wound-healing process may significantly enhance the efficacy of dental implants. Here, we evaluated the potential of "step-type" implant systems to improve the sealing between the peri-implant epithelium (PIE) and the implant surface, and investigated the effect of implant structure on PIE down-growth. MATERIALS AND METHODS: Right maxillary first molars were extirpated from rats and implanted with either a straight-type or a step-type implant varying in step height and/or width (N(s): 0.8 mm height, 0.1 mm width; W(s): 0.8 mm height, 0.2 mm width; H(s): 0.4 mm height, 0.1 mm width). Maxillae were harvested at various time points over 16 weeks to evaluate laminin-5 distribution as an indicator of wound healing and PIE formation, horse-radish peroxidase (HRP) penetration as a measurement of epithelial sealing, and PIE down-growth formation. RESULTS: In all implant models, the PIE formed from the oral sulcular epithelium and spread apically along the implant surface. In the W(s) group, HRP penetration was detected only in the coronal region of the PIE at 4 weeks, whereas in the straight-type, it was observed in the apical region and the connective tissue. At 16 weeks, the W(s) implants exhibited markedly less PIE down-growth than the Con, N(s) or H(s) implants, and were equivalent to that observed in natural teeth. CONCLUSION: The step-type implant system may have the potential for improving epithelial sealing at the tissue-implant interface, as well as reducing apical PIE down-growth, thus enhancing dental implant efficacy.

DOI： 10.1111/j.1600-0501.2011.02163.x

記述言語：日本語  

記述言語：日本語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Local application of fluvastatin improves peri-implant bone quantity and mechanical properties: a rodent study.
Statins are known to stimulate osteoblast activity and bone formation. This study examines whether local application of fluvastatin enhances osteogenesis around titanium implants in vivo. Ten-week-old rats received a vehicle gel (propylene glycol alginate (PGA)) or PGA containing fluvastatin (3, 15, 75 or 300 microg) in their tibiae just before insertion of the implants. For both histological and histomorphometric evaluations undecalcified ground sections were obtained and the bone-implant contact (BIC), peri-implant osteoid volume and mineralized bone volume (MBV) were calculated after 1, 2 and 4 weeks. Using the same models mechanical push-in tests were also performed to evaluate the implant fixation strength. After 1 week the MBV and push-in strength were significantly lower in the 300 microg fluvastatin-treated group than in the other groups (P<0.01). At 2 weeks, however, the BIC and MBV were both significantly higher in the 75 microg fluvastatin-treated group than in the non-fluvastatin-treated groups (P<0.01). Similar tendencies were observed at week 4. Furthermore, the data showed a good correlation between the MBV and the push-in strength. These results demonstrate positive effects of locally applied fluvastatin on the bone around titanium implants and suggest that this improvement in osseointegration may be attributed to calcification of the peri-implant bone.

DOI： 10.1016/j.actbio.2009.10.045

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The effect of a single remote injection of statin-impregnated poly (lactic-co-glycolic acid) microspheres on osteogenesis around titanium implants in rat tibia.
The aim of this study was to evaluate the effects of newly developed injectable poly (lactic-co-glycolic acid) (PLGA) microspheres containing fluvastatin on osteogenesis around titanium implants in the rat tibia. After confirmation of the sustained-release profile of fluvastatin from the microspheres by an in vitro assay, the microspheres were administered to the back skin of the rats by a single transdermal injection. At 2 and 4 weeks after the implant surgery, the fluvastatin groups showed enhanced new bone formation around the titanium implants without any influence on the serum biochemistry. In addition, the fluvastatin groups showed increased three-point bending strengths of their femurs. The results of this study indicate that a single remote injection of PLGA/fluvastatin microspheres safely and successfully stimulated bone formation around titanium implants and increased the mechanical properties of bone.

DOI： 10.1016/j.biomaterials.2010.01.016

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Simvastatin enhances bone formation around titanium implants in rat tibiae

DOI： 10.1111/j.1365-2842.2009.02011.x

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Simvastatin enhances bone formation around titanium implants in rat tibiae

DOI： 10.1111/j.1365-2842.2009.02011.x

記述言語：日本語  

記述言語：日本語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The alternation of peri-implant bone response exposed to static lateral load

DOI： 10.1299/jbse.4.326

記述言語：英語   掲載種別：研究論文（学術雑誌）  

In the present study, peri-implant tissue alteration was studied histologically, and then differences in the gene expression pattern of certain proteins were analyzed using cDNA microarray analysis, under the influence of static lateral load. Beagle dogs were divided into two groups: control and load. Three months after the extraction of mandibular premolars, two implants were placed in each side of the mandible. Each group was further divided into subgroups for loading times of 1, 7 and 14 days. Immediately after the implant installation, a loading device was adhered between the abutments of neighboring implants. Afterward, the expansion screw of the load group was activated by 360-degree rotation, resulting in 0.7 mm horizontal expansion. After sacrificing the dogs, peri-implant tissue was collected, then microarray analysis for the detection of gene expression was performed, as well as histology. Histology indicated that the peri-implant tissue broke down under the influence of the load. Microarray analysis demonstrated the presence of load-sensitive gene expression even after 1 day. Differences in gene expression patterns in concert with static lateral load were demonstrated, even at an early stage post-operation. Further study may help in the diagnosis of pathological overload.

DOI： 10.1299/jbse.4.326

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

PATIENT: A 58-year-old woman presented with a chief complaint of masticatory dysfunction caused by the missing of lower right molars and the detachment of fixed partial denture at the upper right molar region. For this case, implant-retained fixed partial denture with hybrid ceramics facing cast crowns for lower right molar region and conventional fixed partial denture for upper right molar region, considering both the secondary caries and the extrusion of upper right second molar, were fabricated. The patient was followed for >4 years after treatment, and separation between mandibular implant prosthesis and the lower right second premolar was observed during the follow-up period. The interdental separation was treated by refabrication of the prosthesis of the second premolar. DISCUSSION: Physical teeth movement may cause separation between natural tooth and implant-retained prosthesis. CONCLUSION: Functional problems caused by the loss of occlusal support were successfully rehabilitated using implant-retained fixed partial denture.

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

PATIENT: A 58-year-old woman presented with a chief complaint of masticatory dysfunction caused by the missing of lower right molars and the detachment of fixed partial denture at the upper right molar region. For this case, implant-retained fixed partial denture with hybrid ceramics facing cast crowns for lower right molar region and conventional fixed partial denture for upper right molar region, considering both the secondary caries and the extrusion of upper right second molar, were fabricated. The patient was followed for >4 years after treatment, and separation between mandibular implant prosthesis and the lower right second premolar was observed during the follow-up period. The interdental separation was treated by refabrication of the prosthesis of the second premolar. DISCUSSION: Physical teeth movement may cause separation between natural tooth and implant-retained prosthesis. CONCLUSION: Functional problems caused by the loss of occlusal support were successfully rehabilitated using implant-retained fixed partial denture.

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

High and low bone turnover situations, both of which are typically observed as postmenopausal and senile osteoporosis, were created by ovariectomy (OVX), and then an investigation of whether or not the difference of bone turnover affected peri-titanium (Ti) implant osteogenesis in rats was conducted. Female rats were divided into four groups. The experimental and control groups underwent OVX or sham operations at 15 or 27 weeks of age, as high or low bone turnover groups, respectively. Ti implants were inserted into the tibiae at 30 weeks, then fluorochromes were injected 10 or 20 days after the implantation for histometry. The implants were retained for 30 days and then ground sections were prepared. Afterward, the cortical bone growth rate, bone contact ratio (BCR) of the implant in both the cortical bone area and medullary canal area, and the average trabecular bone thickness around the implant were evaluated. Biochemical markers of bone turnover were also measured. Biochemical measurements indicated both increasing osteocalcin production in OVX rats and decreasing tartrate-resistant acid phosphatase activity in the low-turnover group. Histometrical measurements showed decreasing cortical growth and low BCR in the medullary canal of the low-turnover group. The high-turnover group demonstrated BCR as high as that of the control group. There was no significant difference in the average trabecular bone thickness around the implant among the groups. As a result, two types of osteoporotic situations were confirmed and it was shown that the difference of bone turnover was clearly due to the diverse osteogenesis around the Ti implant.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

High and low bone turnover situations, both of which are typically observed as postmenopausal and senile osteoporosis, were created by ovariectomy (OVX), and then an investigation of whether or not the difference of bone turnover affected peri-titanium (Ti) implant osteogenesis in rats was conducted. Female rats were divided into four groups. The experimental and control groups underwent OVX or sham operations at 15 or 27 weeks of age, as high or low bone turnover groups, respectively. Ti implants were inserted into the tibiae at 30 weeks, then fluorochromes were injected 10 or 20 days after the implantation for histometry. The implants were retained for 30 days and then ground sections were prepared. Afterward, the cortical bone growth rate, bone contact ratio (BCR) of the implant in both the cortical bone area and medullary canal area, and the average trabecular bone thickness around the implant were evaluated. Biochemical markers of bone turnover were also measured. Biochemical measurements indicated both increasing osteocalcin production in OVX rats and decreasing tartrate-resistant acid phosphatase activity in the low-turnover group. Histometrical measurements showed decreasing cortical growth and low BCR in the medullary canal of the low-turnover group. The high-turnover group demonstrated BCR as high as that of the control group. There was no significant difference in the average trabecular bone thickness around the implant among the groups. As a result, two types of osteoporotic situations were confirmed and it was shown that the difference of bone turnover was clearly due to the diverse osteogenesis around the Ti implant.

記述言語：日本語  

Dental Implant-bone Interface -Influence of the Surface Geometry-

DOI： 10.4139/sfj.49.682

記述言語：英語   掲載種別：研究論文（学術雑誌）  

THIS STUDY EXAMINED THE INFLUENCE of diabetes mellitus on bone formation around cylindrical titanium (Ti) implants (1.0 mm in diameter and 1.5 mm in length) inserted transcortically and extending into the medullary canal of rat tibiae using light and fluorescence microscopies and image processing. Forty-eight male Wistar King A rats (age 5 weeks) were used in this experiment. Streptozotocin was injected intraperitoneally to induce diabetes and the serum glucose concentration was checked to ensure the induction of diabetes prior to implant placement and at the time of sacrifice. The animals were sacrificed 7, 28, 56, or 84 days after placement. Toluidine blue-stained undecalcified sections were prepared for histological observation and image analysis. The Ti implants in the control group became increasingly encapsulated with a bone layer. The implants in the diabetes-induced (DI) group were also surrounded with a thin bone layer. Abundant adipocytes were observed in the DI group as compared with the control group. Quantitative evaluation indicated that the control group showed a significantly higher percent of bone contact, and thickness of surrounding bone and area than the DI group. Consequently, the present study suggests that uncontrolled diabetes would hinder bone formation around Ti implants in rats.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

THIS STUDY EXAMINED THE INFLUENCE of diabetes mellitus on bone formation around cylindrical titanium (Ti) implants (1.0 mm in diameter and 1.5 mm in length) inserted transcortically and extending into the medullary canal of rat tibiae using light and fluorescence microscopies and image processing. Forty-eight male Wistar King A rats (age 5 weeks) were used in this experiment. Streptozotocin was injected intraperitoneally to induce diabetes and the serum glucose concentration was checked to ensure the induction of diabetes prior to implant placement and at the time of sacrifice. The animals were sacrificed 7, 28, 56, or 84 days after placement. Toluidine blue-stained undecalcified sections were prepared for histological observation and image analysis. The Ti implants in the control group became increasingly encapsulated with a bone layer. The implants in the diabetes-induced (DI) group were also surrounded with a thin bone layer. Abundant adipocytes were observed in the DI group as compared with the control group. Quantitative evaluation indicated that the control group showed a significantly higher percent of bone contact, and thickness of surrounding bone and area than the DI group. Consequently, the present study suggests that uncontrolled diabetes would hinder bone formation around Ti implants in rats.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語  

The purpose of this study was to investigate the tissue reaction to three kinds of membranes, Gore-Tex Augmentation Material (GTAM), Vicryl, and Dura Mater, placed on bone defects around the titanium implants. Nine adult dogs weighing 15kg were used in this study. The dogs were sacrificed either 2, 4, or 12 weeks after placement. Vicryl was exposed 2 weeks after placement. Histologically, it was found that Vicryl was completely resorbed, Dura Mater was replaced with connective tissue at 12 weeks, and bone defects using GTAM and Dura Mater but not Vicryl were partially filled with newly-formed bone tissue. Active bone formation was observed in the space between membranes and pre-existing bone tissue.

DOI： 10.2186/jjps.41.188

記述言語：英語   掲載種別：研究論文（学術雑誌）  

THE PURPOSE OF THIS STUDY was to evaluate the radiologic, histologic, and histometric findings for a retrieved hydroxyapatite (HA)-coated implant which had been placed into a fresh extraction socket with autogenous bone graft 3 months previously. A periapical radiograph disclosed a vertical bone loss around the implant cervix. Examination of histologic sections disclosed that granulation tissue including bone chips around the cervix, and newly-formed bone tissue around the grafted bone tissue on the HA coated surface. In the confocal laser scanning microscopic findings toluidine blue-negative bone tissue showed autofluorescence. Histometric analysis indicated that the average percent bone contact was 29.2% (ranged 26.4% to 34.1%). Suspected reasons for failure were an early exposure of the barrier membrane, its early removal, the implant placement into an infected site, inadequate antibiotic premedication, and/or poor control of infections around teeth prior to implant surgery and around implants before and after placement of barrier membrane.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

THE PURPOSE OF THIS STUDY was to evaluate the radiologic, histologic, and histometric findings for a retrieved hydroxyapatite (HA)-coated implant which had been placed into a fresh extraction socket with autogenous bone graft 3 months previously. A periapical radiograph disclosed a vertical bone loss around the implant cervix. Examination of histologic sections disclosed that granulation tissue including bone chips around the cervix, and newly-formed bone tissue around the grafted bone tissue on the HA coated surface. In the confocal laser scanning microscopic findings toluidine blue-negative bone tissue showed autofluorescence. Histometric analysis indicated that the average percent bone contact was 29.2% (ranged 26.4% to 34.1%). Suspected reasons for failure were an early exposure of the barrier membrane, its early removal, the implant placement into an infected site, inadequate antibiotic premedication, and/or poor control of infections around teeth prior to implant surgery and around implants before and after placement of barrier membrane.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The bone reaction to hydroxyapatite (HA) implants inserted transcortically and extending into the medullary canal of rat tibiae was quantitatively assessed using light microscopy, confocal laser scanning microscopy and an image processing system. Sixty-five male rats (6 weeks old) were divided into two groups, 60 for histological observation and image analysis and five for time-labelling. In the histological observation, control sections of 168 days showed a few bone trabeculae in the fatty bone marrow, and Ti implants had become gradually encapsulated with a thick bone tissue layer; however, HA implants became almost completely encapsulated with a thin bone tissue layer during the 168 day experimental period. Histometrical analysis of the percent bone contact revealed that Ti implants showed a continuous increasing curve, and HA implants showed rapid increase in the initial healing period up to 14 days, with 96% bone contact reaching a plateau at 84 days after operation. There was a significant difference in the percent of bone contact between Ti and HA implants throughout the experimental period. Confocal laser scanning microscopic observations revealed the presence of calcein at the 14th day and only slight alizarin colour layer in the bone tissue at the 28th day, both indicating bone formation. These findings suggest that the activity of bone formation was higher at the 14th day than at the 28th day. Also, the percentage of bone contact of HA is superior to titanium throughout the experimental period, and the ascending patterns of both implants are quite different to each other. (C) 1997 Elsevier Science Limited. All rights reserved.

記述言語：日本語  

The influence of diabetes on the implant-bone interface of titanium (Ti) implants, inserted transcortically and extending into the medullary canal of rat tibiae, was examined, and the differences in bone reaction were quantitatively assessed using an image processing system. Thirty male Wister King A rats (aged 5 weeks) were used in this experiment, and they were divided into 2 groups, 15 for the control and 15 for the diabetes-induced (DI) group. They were sacrificed 7, 28 and 84 days after implant placement. Toluidine blue-stained undecalcified sections were prepared for histological observation and image analysis. The Ti implants in the bone marrow area had been almost encapsulated in a thick bone layer. The Ti implants in the DI group had been partially surrounded by a thin bone layer, but the thickness of the surrounding bone had decreased. Quantitative evaluation indicated that the control group showed an increase of the percent of bone contact, the thickness of surrounding bone and the area of surrounding bone throughout the experimental period, while the DI group showed a decrease of the thickness of surrounding bone and the area of surrounding bone except for the percent of bone contact.

DOI： 10.2186/jjps.41.94

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The bone reaction to hydroxyapatite (HA) implants inserted transcortically and extending into the medullary canal of rat tibiae was quantitatively assessed using light microscopy, confocal laser scanning microscopy and an image processing system. Sixty-five male rats (6 weeks old) were divided into two groups, 60 for histological observation and image analysis and five for time-labelling. In the histological observation, control sections of 168 days showed a few bone trabeculae in the fatty bone marrow, and Ti implants had become gradually encapsulated with a thick bone tissue layer; however, HA implants became almost completely encapsulated with a thin bone tissue layer during the 168 day experimental period. Histometrical analysis of the percent bone contact revealed that Ti implants showed a continuous increasing curve, and HA implants showed rapid increase in the initial healing period up to 14 days, with 96% bone contact reaching a plateau at 84 days after operation. There was a significant difference in the percent of bone contact between Ti and HA implants throughout the experimental period. Confocal laser scanning microscopic observations revealed the presence of calcein at the 14th day and only slight alizarin colour layer in the bone tissue at the 28th day, both indicating bone formation. These findings suggest that the activity of bone formation was higher at the 14th day than at the 28th day. Also, the percentage of bone contact of HA is superior to titanium throughout the experimental period, and the ascending patterns of both implants are quite different to each other. (C) 1997 Elsevier Science Limited. All rights reserved.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/(SICI)1097-4636(199711)37:2<235::AID-JBM13>3.0.CO;2-D

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/S0142-9612(96)00051-8

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Bone-titanium contact was examined in young and mature rats on various days after insertion of pure titanium into the tibia. Under light microscopy, on the 14th day, lamellar mature bone was initially formed, and was seen to make direct contact with the titanium in both groups. In young rats on the 28th day, bone-titanium contact was greater than that in mature animals. On 1-mu m sections, an amorphous zone 0.5-1.0 mu m thick was found around the titanium, and a slender cell layer lay parallel to the implant, forming the superficial layer of the amorphous zone. Ultrastructurally, these slender cells were identified as osteoblastlike cells and made direct contact with the implant via a 20-50-nm thin amorphous zone. Below this cell layer, a collagen-containing, poorly mineralized zone was present and bordered by lamellar bone with a lamina limitans-like structure. However, this cell layer was absent in places, and therefore the thick amorphous zone without slender cell layer consisted ultrastructurally of a 20-50-nm thin amorphous zone and a poorly mineralized zone bordered by the lamellar bone. Sometimes this poorly mineralized zone was absent, and in such cases, the lamellar bone contacted the titanium by the thin amorphous zone formed on the lamina limitans-like structure. Thus, although bone was seen to make contact with the titanium implant, ultrastructurally a 20-50-nm thin amorphous zone, a slender cell layer, and/or a poorly mineralized zone were interposed between the bone and titanium. (C) 1996 John Wiley & Sons, Inc.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Bone-titanium contact was examined in young and mature rats on various days after insertion of pure titanium into the tibia. Under light microscopy, on the 14th day, lamellar mature bone was initially formed, and was seen to make direct contact with the titanium in both groups. In young rats on the 28th day, bone-titanium contact was greater than that in mature animals. On 1-mu m sections, an amorphous zone 0.5-1.0 mu m thick was found around the titanium, and a slender cell layer lay parallel to the implant, forming the superficial layer of the amorphous zone. Ultrastructurally, these slender cells were identified as osteoblastlike cells and made direct contact with the implant via a 20-50-nm thin amorphous zone. Below this cell layer, a collagen-containing, poorly mineralized zone was present and bordered by lamellar bone with a lamina limitans-like structure. However, this cell layer was absent in places, and therefore the thick amorphous zone without slender cell layer consisted ultrastructurally of a 20-50-nm thin amorphous zone and a poorly mineralized zone bordered by the lamellar bone. Sometimes this poorly mineralized zone was absent, and in such cases, the lamellar bone contacted the titanium by the thin amorphous zone formed on the lamina limitans-like structure. Thus, although bone was seen to make contact with the titanium implant, ultrastructurally a 20-50-nm thin amorphous zone, a slender cell layer, and/or a poorly mineralized zone were interposed between the bone and titanium. (C) 1996 John Wiley & Sons, Inc.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

A CLINICAL STUDY WAS CONDUCTED of 59 patients treated with 78 hydroxyapatite (HA)-coated blade implants from August 1986. Five implants in 5 patients were broken at the neck portion, and one implant in one patient was removed from the jaw bone. The histological findings around a broken implant which was removed from the mandible are presented, These sections showed good adaptation of the bone to the implant without a fibrous layer. Histomorphometric evaluation of bone-to-implant contact showed 73.5%. The scanning electron microscopy image of the fractured surface revealed a fatigue fracture. The suspected cause of the fracture was stress concentration at the cervix portion, because of excessive mobility or deleterious change of abutment teeth. Consequently, the osseointegration/biointegration implants should not be connected with natural teeth.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

A CLINICAL STUDY WAS CONDUCTED of 59 patients treated with 78 hydroxyapatite (HA)-coated blade implants from August 1986. Five implants in 5 patients were broken at the neck portion, and one implant in one patient was removed from the jaw bone. The histological findings around a broken implant which was removed from the mandible are presented, These sections showed good adaptation of the bone to the implant without a fibrous layer. Histomorphometric evaluation of bone-to-implant contact showed 73.5%. The scanning electron microscopy image of the fractured surface revealed a fatigue fracture. The suspected cause of the fracture was stress concentration at the cervix portion, because of excessive mobility or deleterious change of abutment teeth. Consequently, the osseointegration/biointegration implants should not be connected with natural teeth.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/(SICI)1097-4636(199604)30:4<523::AID-JBM11>3.0.CO;2-I

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

会議種別：シンポジウム・ワークショップ パネル（公募）  

開催地：Seoul   国名：大韓民国  

会議種別：シンポジウム・ワークショップ パネル（公募）  

開催地：熊本   国名：日本国  

会議種別：シンポジウム・ワークショップ パネル（公募）  

開催地：熊本   国名：日本国  

会議種別：シンポジウム・ワークショップ パネル（公募）  

開催地：熊本   国名：日本国  

記述言語：日本語   会議種別：シンポジウム・ワークショップ パネル（公募）  

開催地：東京都   国名：日本国  

記述言語：英語   会議種別：シンポジウム・ワークショップ パネル（公募）  

開催地：Jeju   国名：大韓民国  

開催年月日： 2009年9月

会議種別：口頭発表（一般）  

開催地：大阪   国名：日本国  

会議種別：シンポジウム・ワークショップ パネル（公募）  

開催地：福岡市   国名：日本国  

会議種別：口頭発表（一般）  

開催地：北九州市   国名：日本国  

記述言語：日本語   会議種別：シンポジウム・ワークショップ パネル（公募）  

開催地：大阪市   国名：日本国  

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：岡山県倉敷市   国名：日本国  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：英語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：英語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：英語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：英語  

記述言語：日本語  

記述言語：日本語  

記述言語：英語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：日本語  

記述言語：英語  

記述言語：日本語  

記述言語：英語  

記述言語：日本語  

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記述言語：日本語   出版者・発行元：(株)ヒョーロン・パブリッシャーズ  

記述言語：日本語   出版者・発行元：(株)ヒョーロン・パブリッシャーズ  

記述言語：日本語   出版者・発行元：(株)ヒョーロン・パブリッシャーズ  

記述言語：英語   出版者・発行元：(公社)日本補綴歯科学会  

記述言語：日本語   出版者・発行元：大阪口腔インプラント研究会  

記述言語：日本語   出版者・発行元：(公社)日本口腔インプラント学会  

口腔インプラント治療は欠損補綴において重要な選択肢となっている.インプラント体を口腔内で機能させるためには骨組織との結合性が重要であることは以前から知られているが,その機能を長期間継続させるには軟組織による封鎖性が不可欠であることも忘れてはいけない.この封鎖機構は,天然歯周囲に存在する生物学的幅径と類似した構造を有している.しかし,インプラント周囲における封鎖機能は,天然歯周囲と比較して明らかに低く脆弱である.その原因として,骨に直接埋入される口腔インプラントの周囲では歯根膜が存在せず,解剖学的に血流が不足していることが挙げられる.さらに組織学的にインプラント体と接着する上皮などの封鎖構造が天然歯と比べて明らかに限局的で少なく,上皮細胞のチタンに対する接着性がそもそも低いことなどから,わずかに存在する接着構造も封鎖機能が低いとされている.そのため,このインプラント周囲における軟組織封鎖性を向上させるため,インプラント体の材質,表面性状,さらに周囲組織の細胞活性に関するさまざまな研究が現在も進められているわけである.このような基礎的研究に対する理解は,適応症例の選別やインプラント体や手技の選択,さらには軟組織を考慮したメインテナンスの実践に役立ち,インプラント治療の長期間の成功につながると期待している.(著者抄録)

記述言語：英語   出版者・発行元：(公社)日本口腔インプラント学会  

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記述言語：日本語   出版者・発行元：(株)第一歯科出版  

記述言語：日本語   出版者・発行元：(公社)日本補綴歯科学会  

公益社団法人日本補綴歯科学会では,教育問題検討委員会を中心として一般社団法人日本歯科専門医機構が求める,補綴歯科専門医を育成するためにふさわしい教育カリキュラムの構築を進めてきたが,このたびカリキュラムが概ね完成したことから,第131回学術大会でそのあらましを報告した.セミナーでは時間の制約もあり,お伝えできなかった項目もあることから,本稿は改めて会員の先生方に教育カリキュラムの内容を知っていただく目的で執筆した.補綴歯科専門医制度のカリキュラム設計は,ファンダメンタルとして補綴歯科専門医の基本知識・技能を学修する基本研修があり,そのうえに大きく分けて症例を基準とした「ケースシリーズベース評価」と,補綴歯科専門医が満たすべき能力の視点からの「コンピテンスベース評価」の二本立ての評価を行う.これらの評価や学習到達度については,いわば実習帳ともいうべき「補綴歯科専門医研修評価記録」に整理する.本稿では主に補綴歯科専門医研修評価記録の記載方法について概説しつつ,機構認定の補綴歯科専門医資格取得に必要な単位,試験について解説する.現在このカリキュラムは各研修機関で試用を行っており,内容の矛盾点や運用上の問題点の改善のために随時改訂を行っていく予定であるが,基本骨格については概ね固まっていると考えていただいて差し支えない.若手補綴歯科医の指導や,教育を受ける若手歯科医師の参考にしていただきたい.(著者抄録)

掲載種別：書評論文，書評，文献紹介等  

Purpose: The aim of this study was to review the literature on current surface modification strategies used to improve the binding efficiency of an emerging biological material, polyetheretherketone (PEEK), with bone and soft tissues. Study selection: This review was based on articles retrieved from PubMed, Google Scholar, Web of Science, and Scien-ceDirect databases. The main keywords used during the search were “polyetheretherketone (PEEK),” “implant,” “surface modification,” “biomaterials,” “bone,” “osseointegration,” and “soft tissue.” Results: The suitability of PEEK surface modification strategies has been critically analyzed and summarized here. Many cell and in vivo experiments in small animals have shown that the use of advanced modification technologies with appropriate surface modification strategies can effectively improve the surface inertness of PEEK, thereby improving its binding efficiency with bone and soft tissues. Conclusions: Surface modifications of PEEK have revealed new possibilities for implant treatment; however, most results are based on in vitro or short-term in vivo evaluations in small animals. To achieve a broad application of PEEK in the field of oral implantology, more in vivo experiments and long-term clinical evaluations are needed to investigate the effects of various surface modifications on the tissue integration ability of PEEK to develop an ideal implant material.

DOI： 10.2186/jpr.JPR_D_22_00138

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記述言語：英語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

DOI： 10.3390/healthcare10061067.

記述言語：日本語   出版者・発行元：(公社)日本口腔インプラント学会  

本邦では口腔外科や補綴,歯周病のいずれかに軸足を置く歯科医師がインプラント治療を担当することが多いように思われる.そのため,特に自身がメインフィールドとする領域以外の治療において正確な難易度を判定する手法があれば,安心安全なインプラント治療を提供することができると考えられる.現在,いくつかのインプラント治療難易度判定ツールが提案されているが,これまでに用いられてきた種々の分類法では難易度をうまく表現できない問題も存在する.たとえば,骨の質,量ともに問題なく咬合にも問題ない下顎臼歯部1歯中間欠損などはイージーケースといっても差し支えないと思われるが,一方で未経験者にとっては,骨をドリリングすること自体が難しく感じられるだろう.このように,ある症例が簡単か難しいかは,術者の感じ方や経験で大きく異なる.また,このような術者間で感じ方に差がある技術的難易度とは別個に,全身状態や治療部位,患者の個性に基づく難易度が存在する.これらの項目に問題がある場合にインプラント治療の成功率が低下することは,多くの場合質が高いエビデンスで裏づけされている.日本口腔インプラント学会研究推進委員会では,Evidence-Based Difficulty Assessment Toolともいえる,術者の経験によらないインプラント治療の難易度分類を試みている.本稿ではその試案を提示する.(著者抄録)

記述言語：日本語   出版者・発行元：(株)デンタルダイヤモンド社  

記述言語：日本語   出版者・発行元：(公社)日本補綴歯科学会  

比較的少数歯の中間欠損症例で,ブリッジあるいはパーシャルデンチャーのどちらでも欠損補綴が可能であるような場合,最終補綴装置の選択に迷うことも少なくない.機能性,審美性,清掃性を備え,かつ長期的な使用に耐えうる補綴装置を製作するためには,比較的シンプルな症例であっても様々なことを考慮して選択・設計を行う必要がある.本稿では「少数歯の中間欠損症例における補綴装置の選択」をテーマとし,ブリッジまたはパーシャルデンチャー,あるいはその両方により対処した症例を供覧して補綴装置の選択理由や選択時の考慮事項について述べる.(著者抄録)

記述言語：英語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

DOI： https://doi.org/10.1016/j.jpor.2016.01.004

記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

記述言語：英語   掲載種別：記事・総説・解説・論説等（学術雑誌）  

Purpose: The aim of this study was to provide an overview on the biology and soft tissue sealing around dental implants and teeth. Study selection: This is a narrative review performed through scientific articles published between 1977 and 2014, indexed in MEDLINE and PubMed databases. The study selected articles that focused on epithelial sealing around dental implant or teeth with cell biology and histology of soft tissue. Results: Implant therapy has been widely applied in dental rehabilitation for many years, with predictable long-term results. The longevity and functionality of dental implants is dependent on both osseointegration around the implant body and the establishment of a soft tissue barrier that protects the underlying hard tissue structures and the implant itself. The health and stability of the peri-implant mucosa also affects the esthetics of the implant. The healing and maintenance of the epithelial and connective tissues around implants are increasingly recognized as being fundamental to implant success. However, there has been little research into the function or formation of the soft tissue seal around dental implants, and the roles of this unique mucosal interface remain unclear. Conclusions: This narrative review explores the extent of the current knowledge of soft tissue barriers around implants from both a basic and clinical perspective, and aims to consolidate this knowledge and highlight the most pertinent questions relating to this area of research.

記述言語：英語   掲載種別：記事・総説・解説・論説等（学術雑誌）