著者

Keisuke Kitagawa Naoki Kodama Yousuke Manda Keitaro Mori Hiroshi Furutera Shogo Minagi

出版者

Japan Prosthodontic Society

雑誌

Journal of Prosthodontic Research (ISSN:18831958)

巻号頁・発行日

pp.JPR_D_21_00171, (Released:2021-12-24)

参考文献数

44

被引用文献数

7

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Purpose: To investigate the effect of masseter muscle activity during wakefulness and sleep on tooth wear.Methods: Sixteen participants with no or mild tooth wear (NMTW group) and sixteen participants with moderate-to-severe tooth wear (MSTW group) were enrolled. The severity of tooth wear was evaluated using the occlusal and incisal indices of the tooth wear index. Surface electromyography was performed to record the electrical activity of the left masseter muscle during wakefulness and sleep. Electromyographic activity was detected using an electromyographic threshold of 5% and 20% of maximal voluntary clenching (MVC). The total duration of electromyographic activity and bruxism episodes were calculated.Results: The mean ages of the NMTW and MSTW groups were 71.75 ± 7.61 years and 71.69 ± 7.49 years, respectively. The mean cumulative duration of electromyographic activity during wakefulness using a threshold of >5% MVC was 6.44 ± 4.52 min/h and 13.62 ± 10.08 min/h for the NMTW and MSTW groups, respectively (p=0.048). The mean total durations of electromyographic activity during wakefulness and sleep using a threshold of >20% MVC were 1.08 ± 1.70 min/h and 1.05 ± 3.02 min/h, respectively, in the NMTW group and 4.78 ± 6.37 min/h and 1.61 ± 1.79 min/h, respectively, in the MSTW group (p=0.048 and p=0.003, respectively).Conclusion: These results suggest that masseter electromyographic activity during wakefulness and sleep may be related to the severity of tooth wear.

著者

Jun Watanabe Yoko Iwamatsu-kobayashi Kenji Kikuchi Tomonari Kajita Hiromitsu Morishima Kensuke Yamauchi Wataru Yashiro Hidekazu Nishimura Hiroyasu Kanetaka Hiroshi Egusa

出版者

Japan Prosthodontic Society

雑誌

Journal of Prosthodontic Research (ISSN:18831958)

巻号頁・発行日

pp.JPR_D_23_00013, (Released:2023-02-22)

参考文献数

52

被引用文献数

2

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Purpose: The hazards of aerosols generated during dental treatments are poorly understood. This study aimed to establish visualization methods, discover conditions for droplets/aerosols generated in simulating dental treatments and identify the conditions for effective suction methods.Methods: The spreading area was evaluated via image analysis of the droplets/aerosols generated by a dental air turbine on a mannequin using a light emitting diode (LED) light source and high-speed camera. The effects of different bur types and treatment sites, reduction effect of intra-oral suction (IOS) and extra-oral suction (EOS) devices, and effect of EOS installation conditions were evaluated.Results: Regarding the bur types, a bud-shaped bur on the air turbine generated the most droplets/aerosols compared with round-shaped, round end-tapered, or needle-tapered burs. Regarding the treatment site, the area of droplets/aerosols produced by an air turbine from the palatal plane of the anterior maxillary teeth was significantly higher. The generated droplet/aerosol area was reduced by 92.1% by using IOS alone and 97.8% by combining IOS and EOS. EOS most effectively aspirated droplets/aerosols when placed close (10 cm) to the mouth in the vertical direction (0°).Conclusions: The droplets/aerosols generated by an air turbine could be visualized using an LED light and a high-speed camera in simulating dental treatments. The bur shape and position of the dental air turbine considerably influenced droplet/aerosol diffusion. The combined use of IOS and EOS at a proper position (close and perpendicular to the mouth) facilitated effective diffusion prevention to protect the dental-care environment.

著者

Sahar Hussein Rifat Falak Kantawalla Stephenie Dickie Piedad Suarez-Durall Reyes Enciso Roseann Mulligan

出版者

Japan Prosthodontic Society

雑誌

Journal of Prosthodontic Research (ISSN:18831958)

巻号頁・発行日

pp.JPR_D_20_00207, (Released:2021-07-15)

参考文献数

67

被引用文献数

11

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Purpose: To evaluate whether poor oral health is associated with a higher risk of malnutrition based on the Mini Nutritional Assessment (MNA) or MNA-SF (short form) in older adults. Study Selection: For this meta-analysis, cohort and cross-sectional studies with adults 65 years and older, reporting oral health outcomes (i.e. edentulism, number of teeth) and either the MNA or MNA-SF were selected. Four electronic databases were searched (Medline via PubMed, Web of Science, Cochrane Library and EMBASE) through June 2020. Risk of bias was assessed with the checklist by the Agency for Healthcare Research and Quality scale. Results: A total of 928 abstracts were reviewed with 33 studies, comprising 27,559 participants, aged ≥65 being ultimately included. Meta-analyses showed that the lack of daily oral hygiene (teeth or denture cleaning), chewing problems and being partially/fully edentulous, put older adults at higher risk of malnutrition (p < 0.05). After adjustment for socio-demographic variables, the included studies reported lack of autonomy for oral care, poor/moderate oral health, no access to the dentist and being edentulous with either no dentures or only one denture were risk factors significantly associated with a higher risk of malnutrition (p < 0.05). Conclusions: These findings may imply that once elders become dependent on others for assistance with oral care, have decreased access to oral healthcare, and lack efficient chewing capacity, there is increased risk of malnourishment. Limitations of the study include heterogeneity of oral health variables and the observational nature of the studies. Further studies are needed to validate our findings.

著者

Sayaka Tada Manabu Kanazawa Anna Miyayasu Maiko Iwaki Murali Srinivasan Shunsuke Minakuchi Gerald McKenna

出版者

Japan Prosthodontic Society

雑誌

Journal of Prosthodontic Research (ISSN:18831958)

巻号頁・発行日

pp.JPR_D_20_00170, (Released:2021-05-11)

参考文献数

23

被引用文献数

3

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Purpose: The aim of this study was to evaluate patients’ economic preferences for two different tooth replacement strategies for the edentulous mandible namely conventional complete dentures (CCDs) and implant overdentures supported by two implants (IODs), using a willingness-to-pay (WTP) analysis. Methods: Twenty-six elderly patients who had been rehabilitated with either a mandibular CCD or IOD were invited to participate in this study. All participants were provided with the details of the two treatment protocols, including advantages, disadvantages, and treatment costs. The patients were then asked to indicate their maximum WTP values for each protocol using a payment card method for contingency evaluation. Results: Fifteen patients with mandibular CCD (CCD-Group) and 12 patients with IOD (IOD-Group) participated in the study. Overall, the median and maximum WTP values recorded for IOD therapy were significantly higher than those for CCD therapy (p<0.05). Both treatment groups recorded maximum WTP values for CCD therapy, which exceeded the market cost (¥30,000 [US$280]), CCD-Group: ¥50,000 (interquartile range [IQR]: 40,000 – 65,000), and IOD-Group: ¥45,000 (IQR: 30,000–85,000)]. However, both groups registered a median and maximum WTP values for IOD therapy lower than the market cost (¥780,000 [US$7,300]), (CCD-Group: ¥500,000 [IQR: 300,000 - 750,000], IOD-Group: ¥700,000 [IQR: 500,000–800,000]). Conclusion: The maximum WTP values recorded for IOD therapy were significantly higher than CCD therapy in both treatment groups. While patients were willing to pay more than the current market costs for CCDs, they were not willing to meet the market value for IODs.

著者

Yo Akiyama Manabu Kanazawa Maiko Iwaki Tamaki Hada Yumika Soeda Ryosuke Otake Kenta Kashiwazaki Yuriko Komagamine Natsuko Murakami Atsushi Takaichi Noriyuki Wakabayashi Shunsuke Minakuchi

出版者

Japan Prosthodontic Society

雑誌

Journal of Prosthodontic Research (ISSN:18831958)

巻号頁・発行日

pp.JPR_D_22_00100, (Released:2023-02-02)

参考文献数

17

被引用文献数

2

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Purpose: Although digital removable partial dentures have been previously described, there have been no reports on how to fabricate them in one piece. This study proposes a new method for fabricating patient-specific digital removable partial dentures using a custom plate.Methods: First, a gypsum model was scanned using a laboratory scanner and a removable partial denture was designed using computer-aided design (CAD) software based on standard tessellation language data. The metal clasp was fabricated from Ti-6Al-4V using a 3D printer. For custom plate fabrication, a resin plate frame was designed using computer-aided design (CAD) software and fabricated using a 3D printer. An artificial tooth and metal clasp were fixed on the base surface of the frame, an auto-polymerizing resin was poured into the frame for the denture base, and the artificial tooth and metal clasp were packed to form a custom plate. The plate was cut using a milling machine. Subsequently, the support attached to the denture was removed and polished for complete fabrication of the denture.Conclusions: Our novel removable partial denture fabrication method is more efficient than the conventional method. The obtained removable partial dentures demonstrated satisfactory accuracy.

著者

Kohei Yamaguchi Kazuharu Nakagawa Kanako Yoshimi Chantaramanee Ariya Ayako Nakane Takuma Okumura Haruka Tohara

出版者

Japan Prosthodontic Society

雑誌

Journal of Prosthodontic Research (ISSN:18831958)

巻号頁・発行日

pp.JPR_D_21_00296, (Released:2022-06-22)

参考文献数

40

被引用文献数

2

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Purpose: This study aimed to investigate the relationship between tongue factors (tongue strength and tongue volume), systemic factors (grip strength and walking speed), and the extracellular water/total body water ratio.Methods: This cross-sectional study included community-dwelling adults. Body water composition and skeletal muscle mass index were measured using bioelectrical impedance analysis. Moreover, tongue grip strength, tongue volume, occlusal support condition (Eichner classification), and walking speed were measured. Multiple linear regression analysis was performed to investigate the relationship between the tongue and systemic factors as dependent variables and body water composition.Results: We included 171 community-dwelling adults (62 men and 109 women) aged 70.0 years (interquartile range: 8). Tongue strength (r=-0.22, p=0.004) and grip strength (r=-0.39, p<0.001) were correlated with the extracellular water/total body water ratio. In multiple linear regression analysis, tongue strength was associated with the extracellular water/total body water ratio (β=-0.20, p=0.034), and grip strength was associated with the extracellular water/total body water ratio (β=-0.12, p=0.047), sex, body mass index, skeletal muscle mass index, and occlusal support condition.Conclusions: A higher extracellular water/total body water ratio indicates lower tongue and grip strength. Dentists and dental hygienists should be aware of systemic factors present in patients with lower tongue and grip strength. These findings may lead to further medical investigations and diagnosis of other systemic diseases.

著者

Shiho Kino Yudai Tamada Kenji Takeuchi Atsushi Nakagomi Koichiro Shiba Taro Kusama Takafumi Yamamoto Jun Aida

出版者

Japan Prosthodontic Society

雑誌

Journal of Prosthodontic Research (ISSN:18831958)

巻号頁・発行日

pp.JPR_D_23_00091, (Released:2023-08-11)

参考文献数

48

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Purpose: A growing body of evidence suggests that oral health is associated with a wide range of health outcomes; however, opinions tend to vary because of inconsistent findings. This study aimed to simultaneously examine the association between oral health status and multiple health and well-being indicators using outcome-wide epidemiology.Methods: Data were obtained from the Japan Gerontological Evaluation Study. Oral health status was categorized as: ≥20 teeth, 10-19 teeth with dental prosthesis, 0-9 teeth with prosthesis, 10-19 teeth without prosthesis, and 0-9 teeth without prosthesis. We examined the associations between oral health status in 2013 and 35 health and well-being outcomes in 2019, including physical/cognitive health, psychological distress, subjective health, social well-being, prosocial/altruistic behaviors, and health behaviors, using two databases (n=32,827 and 15,905).Results: Compared to individuals with ≥20 teeth, those with <20 teeth had a 10-33% higher risk of mortality and a 7-10% higher risk of functional disability six years later. Additionally, individuals with fewer than 20 teeth tended to go out less frequently and eat fewer vegetables and fruits. Furthermore, individuals with 0-9 teeth without a prosthesis were more likely to have severe functional disability (risk ratio (RR):1.17, 95% confidence interval (CI):1.05-1.31), engage in fewer intellectual activities (standardized difference: 0.17, 95% CI: 0.10-0.24), and feel more hopeless (RR: 1.21, 95% CI: 1.04-1.41).Conclusions: The prevention of tooth loss and prosthodontic treatment may be associated with reduced mortality and functional disability, as well as maintenance of intellectual ability, frequency of going out, and improvements in dietary lifestyle.

著者

Yohei Hama Akemi Hosoda Chieko Kubota Ruoyan Guo Hitomi Soeda Kohei Yamaguchi Mitsuzumi Okada Shunsuke Minakuchi

出版者

Japan Prosthodontic Society

雑誌

Journal of Prosthodontic Research (ISSN:18831958)

巻号頁・発行日

pp.JPR_D_22_00137, (Released:2022-11-09)

参考文献数

46

被引用文献数

4

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Purpose: Maintaining good masticatory function from a young age promotes lifelong health, yet limited studies have explored masticatory performance in young individuals. We investigated the relationship of sex, age, and individual oral functions with masticatory performance among junior and senior high school students and young adults.Methods: This cross-sectional study included students aged 12–13, 14–15, and 16–17 years (groups S1, S2, and S3, respectively) and young adults aged 20–40 years (group YA). We assessed oral functions, the number of functional teeth, and anthropometric measurements. Masticatory performance was evaluated using color-changeable chewing gum. We analyzed sex-related differences in each group and age-related differences in each sex. Multiple linear regression analysis was performed using masticatory performance as the dependent variable to investigate related factors.Results: Among the 522 children and 100 young adults, males exhibited significantly higher masticatory performance than females in groups S1, S3, and YA. Among males, groups S2, S3, and YA exhibited significantly higher masticatory performance than group S1. Among females, group S2 exhibited higher masticatory performance than groups S1 and S3. Male sex, the maximum occlusal force and tongue pressure, and the number of functional teeth were significantly correlated with masticatory performance.Conclusions: Masticatory function development differed by sex, with males exhibiting higher masticatory performance than females. We identified that male sex, the maximum occlusal force and tongue pressure, and the number of functional teeth were significantly associated with masticatory performance. Our findings provide a basis for masticatory performance assessment in different age groups.

著者

Ryuji Hosokawa

出版者

Japan Prosthodontic Society

雑誌

Journal of Prosthodontic Research (ISSN:18831958)

巻号頁・発行日

vol.65, no.2, pp.65.2_vi, 2021 (Released:2021-06-30)

参考文献数

5

被引用文献数

2

著者

河相 安彦 矢崎 貴啓 松丸 悠一 先崎 孝三郎 浅井 秀明 今道 康夫 伊藤 允人 杉村 華織 竹尾 藍 朱 一慶 伊澤 武志 大野 洋介 山本 史朗 小平 真倫亜 宗 邦雄 島 由樹 林 幸男 桑原 克久 小林 喜平

出版者

Japan Prosthodontic Society

雑誌

日本補綴歯科學會雜誌 = The journal of the Japan Prosthodontic Society (ISSN:03895386)

巻号頁・発行日

vol.51, no.3, pp.572-581, 2007-07-10

被引用文献数

3 7

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目的: 本研究の目的は総義歯学の授業で講義型学習 (以下LBL) と問題解決型学習 (以下PBL) 双方を経験した学生の自己学習および臨床推理能力に関する教育効果と授業・教員に対する評価の両教育形式間での比較検討である.<BR>方法: 総義歯学の授業を平成15年度入学の学生に, 平成17年度3年次前期にLBL, 平成18年度4年次前期にPBLにて行った. PBLは5回にわたり, 毎回1症例についてグループディスカッションを行い, グループによるまとめを2回, 個人レポートを2回および全体発表を1回という予定で進行した. 全体発表終了後, 教育効果および授業・教員に関する27項目のアンケートを行った.因子分析により質問項目の類型を行い, 各質問項目についてLBLおよびPBLの比較を行った (Paired-t).<BR>結果: 因子分析より質問項目は4因子に類型された. LBLとPBLとの間で「学習態度」について7項目中4項目, 「臨床推理能力」について全項目, 「授業内容」について7項目中5項目, 「教員評価・そのほか」について6項目中2項目, 合計27項目中18項目 (66.6%) でPBLが有意に高い値を示した.<BR>結論: PBLはLBLに比べ自己学習および臨床推理能力の教育効果の向上に極めて有効で, 授業に関する評価も有意に高かった. 一方, 同様の授業を受けることに学生は後向きで, 消極性解消法の検討が必要であると示唆された.

著者

Ting Wang Jukka Pekka Matinlinna Michael Francis Burrow Khaled Elsayed Ahmed

出版者

Japan Prosthodontic Society

雑誌

Journal of Prosthodontic Research (ISSN:18831958)

巻号頁・発行日

pp.JPR_D20_00031, (Released:2021-02-22)

参考文献数

84

被引用文献数

2

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Purpose: Fiber-reinforced composites (FRCs) have received considerable attention, owing to their potential use in dental prostheses or bone fracture fixation applications. The aim of this systematic review was to analyze and report the biological properties of FRCs reported in the existing literature. Study selections: A systematic search of four databases (PubMed/MEDLINE, Scopus, Web of Science, and Cochrane library) was performed to identify all relevant studies published between 1962 and 2019. The search was limited to laboratory-based studies published in English. Citation mining was also performed through cross-referencing of included studies and hand searching of relevant journals. Results: A total of 1283 potentially relevant articles were initially identified, and thirty-three articles were full-text screened. In the final ten studies included for review, four investigated bacterial adhesion and growth abilities on FRCs, four investigated the fibroblastic cytotoxicity of different surface-treated FRCs, and two investigated the osseointegration between bone and FRCs. Owing to the heterogeneity of fiber types, FRC-coating, and lack of standardized testing protocols, a meta-analysis was not feasible. The included studies indicated that glass fibers, and in particular E-glass fibers, are superior to ceramics and other FRCs in terms of bacterial adherence, fibroblast cytotoxicity, and cell viability. Conclusions: Glass-fiber-reinforced composites are cytocompatible materials that possess satisfactory biological properties and can be used in dental prosthesis and craniofacial implants. Further research is necessary to regulate the matrix ion release/degradation of FRCs to prolong the initially demonstrated properties.

著者

Michael H. Walter Jens Dreyhaupt Torsten Mundt Ralf Kohal Matthias Kern Angelika Rauch Frank Nothdurft Sinsa Hartmann Klaus Böning Julian Boldt Helmut Stark Daniel Edelhoff Bernd Wöstmann Ralph Gunnar Luthardt Wolfgang Hannak Stefan Wolfart Guido Heydecke Florentine Jahn Peter Pospiech Birgit Marré

出版者

Japan Prosthodontic Society

雑誌

Journal of Prosthodontic Research (ISSN:18831958)

巻号頁・発行日

vol.64, no.4, pp.498-505, 2020 (Released:2020-08-08)

参考文献数

29

被引用文献数

7

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Purpose: This analysis focused on periodontal health in shortened dental arches (SDAs). Methods: In a randomized controlled clinical trial, patients with missing molars in one jaw and at least one premo-lar and canine on both sides were eligible for participation. In the partial removable dental prosthesis (PRDP) group ( n = 79), molars were replaced with a precision attachment retained PRDP. In the SDA group ( n == 71), the SDA up to the second premolars was either left as is or restored with fixed den- tal prostheses. Outcome variables were vertical clinical attachment loss (CAL-V), pocket probing depth (PPD), bleeding on probing (BOP) and plaque index (PLI). For CAL-V and PPD, the changes at six mea- suring points per tooth were analyzed. For BOP and PLI, patient related rates were calculated for each point in time. Statistical methods included linear regression analyses. Results: In the intention-to-treat (ITT) analysis for CAL-V in the study jaw, the 10 year patient related mean changes were 0.66 mm in the PRDP group and −0.13 mm in the SDA group. The resulting mean patient related group difference of 0.79 mm (95% CI: 0.20 mm–1.38 mm) was significant ( p = 0.01). There were no significant differences in the ITT analyses for PPD. For BOP and PLI, significant group differences with more favorable results for the SDA group were found. Conclusions: In view of lacking substantial differences for CAL-V and PPD, the overall differences were considered of minor clinical relevance. The results add confirmatory evidence to the shortened dental arch concept and its clinical viability (controlled-trials.com ISRCTN97265367).

著者

松下 恭之 佐々木 健一 郡 英寛 江崎 大輔 春田 明日香 古谷野 潔

出版者

Japan Prosthodontic Society

雑誌

日本補綴歯科學會雜誌 = The journal of the Japan Prosthodontic Society (ISSN:03895386)

巻号頁・発行日

vol.52, no.1, pp.1-9, 2008-01-10

参考文献数

41

被引用文献数

7 1

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オッセオインテグレーションインプラントは, 表面性状の改善や埋入システムの確立により, 5年程度の中期経過では100%に近い生存率も報告されている. しかし一方で長期の使用に伴い, 破折などの機械的偶発症と支持骨の吸収などの生物学的偶発症が増加することが報告されている. この原因は多様だが, インプラントに付与した咬合から生じたオーバーロードが偶発症の主な因子のひとつとして上げられている。<br>インプラントの咬合において, オーバーロードを引き起こすと考えられるリスクファクターについて疫学研究と基礎的研究のレビューを通して, 現状を整理した.<br>天然歯とインプラントが混在する場合の咬合については, 当初被圧変位量の差を考慮すべきとされたが, 現在これを積極的に肯定する研究は少なく, むしろ被圧変位量の分だけ低くした咬合を付与した場合に, 顎関節や隣在歯などへの影響を危惧する報告も散見される. 現状では, 天然歯と同様の接触を与えても臨床的な問題は少ないと考えられる.<br>側方ガイドや咬合力の側方成分, カンチレバー, 広すぎる咬合面幅によるオフセットローディングなどの非軸方向荷重については, 曲げモーメントとして作用するため, 軸方向荷重よりもその影響は強いと思われる. しかしながら生物学的に影響ありとした疫学データは見られない.<br>天然歯とインプラントの連結については, メタ解析の結果により骨吸収へのリスクが示唆されている.

著者

Harukazu Kanehira Akinori Agariguchi Hisashi Kato Shigeki Yoshimine Hiroshi Inoue

出版者

Japan Prosthodontic Society

雑誌

日本補綴歯科学会雑誌 (ISSN:03895386)

巻号頁・発行日

vol.52, no.3, pp.375-380, 2008-07-10 (Released:2008-10-10)

参考文献数

49

被引用文献数

17 31

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Purpose: To evaluate the causes of temporomandibular disorder (TMD) by examining the relationships between 3 major TMD symptoms, parafunction, and stress, a questionnaire survey was performed during dental examinations in corporations.Methods: The survey was performed using 6 questions on the following topics: 1. Trismus; 2. Joint noise; 3. Pain; 4. Clenching in the daytime; 5. Nocturnal bruxism; and 6. Stress.There were 3,225 subjects, 2,809 males and 416 females and the mean age of the subjects was 40.12 years. The relationships between questions 1 to 5 and question 6 were examined by the chi-square test.Results: There were significant correlations (question 1, p=0.001; questions 2-5, p<0.001).Conclusion: Clearly, there was an influence of psychological factors, such as stress, on TMD, and such factors were considered to play important roles in its etiology, progression, and treatment. The results of this study suggest that well-controlled studies of TMD are necessary.

著者

原田 美紀 猪子 芳美 清水 公夫 森田 修己

出版者

Japan Prosthodontic Society

雑誌

日本補綴歯科學會雜誌 = The journal of the Japan Prosthodontic Society (ISSN:03895386)

巻号頁・発行日

vol.48, no.5, pp.733-740, 2004-10-10

被引用文献数

5 5

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目的: 本研究は, 閉塞型睡眠時無呼吸症候群 (OSAS) 患者に下顎前方位型口腔内装置 (PMA) を用い, 切歯点の移動と口腔咽頭腔前後径が直接関係するという仮説を検証し, PMAの治療効果を示す睡眠時の動脈血酸素飽和度を検討することである.<BR>方法: OSAS患者19名にPMAを適用し, PMA装着前と装着時における側方頭部X線規格写真撮影と動脈血酸素飽和度測定を行い, 側方頭部X線規格写真より, 口腔咽頭腔前後径 (PNS-AS, SPAS, MAS, IAS) と切歯点の移動量を計測し, 動脈血酸素飽和度より動脈血酸素飽和度低下指数 (ODI) 4%値および晦中飽和酸素濃度90%未満低下時間比 (CT<SUB>90</SUB>) を算出した.分析は, 切歯点移動量と咽頭腔前後径変化量についてはSpearmanの順位相関を, PMA装着前と装着時のODI4%値, CT<SUB>90</SUB>, 咽頭腔前後径についてはWilcoxonの符号付順位検定を用いて検討した.<BR>結果: 切歯点の前方移動量と口腔咽頭腔前後径のIAS部増加量との間に相関が認められた (r=0.61, p=0.01).PMA装着時のODI4%値とCT<SUB>90</SUB>は有意に減少し (p<0.01), 咽頭腔前後径のSPAS, MAS, IASは, 有意に増加した (P<0.01).<BR>結論: OSAS患者に対するPMA装着による下顎前方移動は, 口腔咽頭腔前後径を拡大させ, 動脈血酸素飽和度の改善に寄与することが示された.

出版者

Japan Prosthodontic Society

雑誌

Journal of Prosthodontic Research (ISSN:18831958)

巻号頁・発行日

vol.60, no.1, pp.12-19, 2016-01-25 (Released:2016-03-31)

被引用文献数

539

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Purpose: Polyetheretherketone (PEEK) is a polymer that has many potential uses in dentistry. The aim of this review was to summarize the outcome of research conducted on the material for dental applications. In addition, future prospects of PEEK in the field of clinical dentistry have been highlighted. Study selection: An electronic search was carried out via the PubMed (Medline) database using keywords ‘polyetheretherketone', ‘dental' and ‘dentistry' in combination. Original research papers published in English language in last fifteen year were considered. The studies relevant to our review were critically analyzed and summarized. Results: PEEK has been explored for a number of applications for clinical dentistry. For example, PEEK dental implants have exhibited lesser stress shielding compared to titanium dental implants due to closer match of mechanical properties of PEEK and bone. PEEK is a promising material for a number of removable and fixed prosthesis. Furthermore, recent studies have focused improving the bioactivity of PEEK implants at the nanoscale. Conclusion: Considering mechanical and physical properties similar to bone, PEEK can be used in many areas of dentistry. Improving the bioactivity of PEEK dental implants without compromising their mechanical properties is a major challenge. Further modifications and improving the material properties may increase its applications in clinical dentistry.

著者

Kento Odaka Shota Kamiyama Naoki Takano Yoshihiko Uematsu Satoru Matsunaga

出版者

Japan Prosthodontic Society

雑誌

Journal of Prosthodontic Research (ISSN:18831958)

巻号頁・発行日

pp.JPR_D_23_00074, (Released:2023-08-24)

参考文献数

37

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Purpose: This study aims to develop a numerical prediction method for the average and standard deviation values of the largely varied fatigue life of additively manufactured commercially pure titanium (CPTi grade 2) clasps. Accordingly, the proposed method is validated by applying it to clasps of different shapes.Methods: The Smith-Watson-Topper (SWT) equation and finite element analysis (FEA) were used to predict the average fatigue life. The variability was expressed by a 95% reliability range envelope based on the experimentally determined standard deviation.Results: When predicting the average fatigue life, the previously determined fatigue parameters implemented in the SWT equation were found to be useful after conducting fatigue tests using a displacement-controlled fatigue testing machine. The standard deviation with respect to stroke and fatigue life was determined for each clasp type to predict variability. The proposed prediction method effectively covered the experimental data. Subsequently, the prediction method was applied to clasps of different shapes and validated through fatigue tests using 22 specimens. Finally, the fracture surface was observed using scanning electron microscopy (SEM). Many manufacturing process-induced defects were observed; however, only the surface defects where the maximum tensile stress occurred were crucial.Conclusions: It was confirmed that the fatigue life of additively manufactured pure titanium parts is predictable before the manufacturing process considering its variability by performing only static elasto-plastic FEA. This outcome contributes to the quality assurance of patient-specific clasps without any experimental investigation, reducing total costs and response time.

著者

Kazuya Yoshida

出版者

Japan Prosthodontic Society

雑誌

Journal of Prosthodontic Research (ISSN:18831958)

巻号頁・発行日

vol.62, no.2, pp.239-244, 2018 (Released:2018-05-08)

参考文献数

35

被引用文献数

30

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Purpose: Many patients with oromandibular dystonia, which is characterized by involuntary masticatory, lower facial, and/or tongue muscle contractions, experience relief of symptoms through sensory tricks such as eating chewing gum or candy. The aim of this study was to identify the factors influencing the effects of splints in patients with oromandibular dystonia.Methods: Occlusal splints were inserted in 128 patients (89 women, 39 men) with oromandibular dystonia (102 with jaw closing dystonia, 20 with lingual dystonia, 5 with jaw deviation dystonia, 4 with jaw opening dystonia, 3 with lip dystonia, and 2 with jaw protrusion dystonia). Patients who showed improvement with the use of splints and continued to wear them for at least 3 months were defined as responders. In contrast, patients who showed little or no effect and/or were unable to insert splints were defined as non-responders. Differences in demographic and clinical data were statistically compared between responders and non-responders.Results: Ninety-eight patients (76.6%) were responders (subjective improvement: 30.5%). Thirty patients (23.4%) were non-responders (subjective improvement: 7.2%). The responders were significantly older than the non-responders (53.8 years vs 47.0 years; p < 0.05). Patients with jaw closing dystonia showed the most favorable results. The proportion of patients with sensory tricks was significantly higher in responders than in non-responders (66.3% vs 26.7%; p < 0.05).Conclusions: The sensory trick splint is especially helpful for patients with jaw closing dystonia. It is useful, although partially effective, as an alternative therapy in patients for whom other therapies have been unsatisfactory.

著者

Paula Pontevedra Carlos Lopez-Suarez Veronica Rodriguez Celia Tobar Jesus Pelaez Maria J Suarez

出版者

Japan Prosthodontic Society

雑誌

Journal of Prosthodontic Research (ISSN:18831958)

巻号頁・発行日

pp.JPR_D_22_00237, (Released:2023-03-28)

参考文献数

55

被引用文献数

1

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Purpose: To evaluate and compare the survival, success rates, and biological and technical complications of three-unit posterior monolithic and veneered zirconia and metal-ceramic (MC) posterior fixed partial dentures (FPDs) fabricated using a digital workflow and computer-aided design and computer-aided manufacturing (CAD/CAM) over a 5-year follow-up.Methods: Ninety patients in need of three-unit posterior FPDs were randomized to receive monolithic zirconia (MZ), veneered zirconia (VZ), and MC restorations (n = 30 each). Teeth preparations were scanned using an intraoral scanner, and restorations were milled and cemented with resin cement. Clinical performance and periodontal parameters were assessed at baseline and yearly up to 5 years after insertion. Data analysis was performed using the Kaplan-Meier method, Friedman test, and Wilcoxon signed-rank test with Bonferroni correction and Mann-Whitney U test.Results: The 5-year survival rates of the MZ, VZ, and MC FPDs were 87%, 97%, and 100%, respectively (P = 0.04). Most complications were biological in nature. Only one MZ FPD fractured 58 months after placement. All the restorations were assessed as satisfactory at each recall. Differences were found in the gingival index score over time in the VZ and MC groups. The margin index remained stable throughout the follow-up period in both zirconia groups.Conclusions: The results of this study suggest that using a digital workflow to fabricate posterior FPDs is an adequate treatment option and that monolithic zirconia could be a viable alternative to metal-ceramic or veneered zirconia. However, further long-term studies are necessary to provide stronger evidence in patients with bruxism.

著者

Takahiko Sakai Hefei Li Tatsuki Shimada Suzune Kita Maho Iida Chunwoo Lee Tamaki Nakano Satoshi Yamaguchi Satoshi Imazato

出版者

Japan Prosthodontic Society

雑誌

Journal of Prosthodontic Research (ISSN:18831958)

巻号頁・発行日

pp.JPR_D_22_00053, (Released:2022-08-25)

参考文献数

38

被引用文献数

12

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Purpose: This study aimed to develop an artificial intelligence (AI) model to support the determination of an appropriate implant drilling protocol using cone-beam computed tomography (CBCT) images.Methods: Anonymized CBCT images were obtained from 60 patients. For each case, after implant placement, images of the bone regions at the implant site were extracted from 20 slices of CBCT images. Based on the actual drilling protocol, the images were classified into three categories: protocols A, B, and C. A total of 1,200 images were divided into training and validation datasets (n = 960, 80%) and a test dataset (n = 240, 20%). Another 240 images (80 images for each type) were extracted from the 60 cases as test data. An AI model based on LeNet-5 was developed using these data sets. The accuracy, sensitivity, precision, F-value, area under the curve (AUC) value, and receiver operating curve were calculated.Results: The accuracy of the trained model is 93.8%. The sensitivity results for drilling protocols A, B, and C were 97.5%, 95.0%, and 85.0%, respectively, while those for protocols A, B, and C were 86.7%, 92.7%, and 100%, respectively, and the F values for protocols A, B, and C were 91.8%, 93.8%, and 91.9%, respectively. The AUC values for protocols A, B, and C are 98.6%, 98.6%, and 99.4%, respectively.Conclusion: The AI model established in this study was effective in predicting drilling protocols from CBCT images before surgery, suggesting the possibility of developing a decision-making support system to promote primary stability.