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Purpose To investigate the effect of prosthodontic treatment on the ingestible food profile in adult Japanese outpatients, and to identify the related risk factors that can deteriorate the profile.Methods The participants were 277 outpatients who visited university-based specialty clinics in Japan for prosthodontic treatment. The demographic data, number of present teeth assessed via intraoral examination, and oral health-related quality of life assessed by the total Oral Health Impact Profile (OHIP-J54) scores of all participants were recorded before treatment. Ingestible food profile score (IFS) was recorded using a validated food intake questionnaire. Eligible participants who answered the questionnaire before and after treatment were categorized into five groups based on the prosthodontic treatments they received (i.e., crowns, bridges, removable partial dentures, removable complete dentures, and removable complete and partial dentures).Results Multivariate analysis of covariance revealed a statistically significant main effect of prosthodontic intervention (time course: before and after treatment) on mean IFS (p=0.035, F=4.526), even after adjusting for covariates (age, number of present teeth, and treatment modality). Multiple linear regression analysis revealed that the low number of present teeth (r=0.427, p0.001) and a high OHIP-J54 total score (r=-0.519, p0.001) of the patients at the baseline were significantly associated with their baseline IFSs, even after adjusting for confounding variables.Conclusions The findings of this multicenter follow-up study indicate the importance of prosthodontic rehabilitation in improving patients' ingestible food profiles.

BackgroundThe diagnostic assessment of the level of difficulty in treating patients who need prosthodontic care is useful to establish a medico-economically efficient system with primary care dentists and prosthodontic specialists.Materials and methodsA multi-axis assessment protocol was established using the newly established treatment difficulty indices. The protocol contains Axis I: oral physiological conditions (e.g., teeth damage and/or missing teeth); Axis II: general health and sociological conditions (e.g., medical disorders); Axis III: oral health-related quality of life (OHRQOL; e.g., oral health impact profile: OHIP); and Axis IV: psychological health (e.g., mood, anxiety, somatoform disorders). A preliminary study on the test–retest consistency of the protocol was conducted to check the levels of reliability of the indices prior to a large-scale, multi-center cohort study on the validity of the protocol.ResultsThe test–retest consistency in terms of the oral physiological condition (Axis I) after data reduction was 0.63 for patients with teeth problems, 0.95 for partially edentulous patients, and 0.62 for edentulous patients. The reliability for general health and sociological conditions (Axis II), OHRQOL (Axis III), and psychological health (Axis IV) were 0.88, 0.74, and 0.61, respectively. These values reflect either “sufficient agreement” or “excellent agreement” in accordance with the criteria established by Landis and Koch (1977) [1].ConclusionThis protocol is the first multi-axis assessment scheme introduced for prosthodontic treatment with sufficient reliability. This new system is therefore expected to have a significant impact on future dental diagnostic nomenclature systems.

Purpose The purpose of this study was to determine the durability of the peel bond of commercial resilient denture liners to a denture base resin using a thermal cycling test. Methods Eight commercial resilient denture liners (five silicone and three acrylic) were used in the study. The samples were exposed to thermal cycles between 5°C and 55°C for 1min for 0, 1,250, 2,500, 5,000 and 10,000 cycles. The test samples were placed under tension until failure in a materials testing machine using a crosshead speed of 20mm/min. The modes of debonding were characterized as tear, peel or snap. Statistical analysis was performed using one-way and two-way analysis of variance and Student–Newman–Keuls multiple comparison tests ( α =.05). Results A significant difference was found between different resilient denture liners for peel bond strength at 0 cycles. No extreme influence on the peel bond strength was observed under any of the thermal cycles. The snap mode of debonding was observed in most samples of all materials for all cycles. Conclusion All resilient denture liners tested had a sufficiently strong bond to the denture base resin. Within the limitations of this study, the results show that all of the materials were acceptable for clinical use, having met the accepted adequate bond strength for resilient denture liners of 0.45MPa.

厚生労働省は本年 6月,介護を受けたり寝たきりに なったりせず,制限なく健康な日常生活を送ることが可 能な期間を示す「健康寿命」が,2010 年で男性が 70.42 歳,女性が 73.62 歳だったとする算出結果を発表した. 一方,平均寿命は 2010 年には男性で 79.64 歳,女性 で 86.39 歳であったことから,健康寿命との差は男性 で 9.22 年,女性で 12.77 年もみられた.平均寿命と 健康寿命との差は日常生活に制限がある「不健康な期間」 で,この差が拡大すれば医療費や介護給付費を多く消費 する期間が増加することになる. われわれ補綴歯科を担う研究者・臨床医は,平成 16 年に日本学術会議第 7部咬合学研究連絡委員会が作成 した対外報告「咬合・咀嚼が創る健康長寿」が提言し た内容を踏まえ,「咬合・咀嚼が創る健康長寿」を学術 大会のメインテーマに掲げ,健康寿命の延伸に果たす咬 合・咀嚼の役割を会員や国民に強調してきた.健康長寿 を達成するためには,要支援や要介護の状態にならない ようにすること,あるいはもし要支援や要介護の状態に なったとしてもその状態がそれ以上悪くならないように することがきわめて重要であり,これが「介護の予防」 や「介護の重症化の予防」である.補綴歯科は,咬合・ 咀嚼・嚥下の「機能」を回復することを通して,われわ れが従来考えていたよりもはるかに大きなインパクトを 「介護の予防」や「介護の重症化の予防」に与えている. 「介護予防」・「介護の重症化の予防」には,1口腔機 能の向上,2運動器の機能向上,3栄養改善,の 3つ の柱が重要とされている が,これらに対して,いく つかのよく計画された介入研究の結果から,補綴歯科治 療がもたらす咬合・咀嚼・嚥下機能の回復・維持が,口 腔機能の向上はもとより,運動器の機能向上や高齢者の 栄養の改善にも大きく貢献することが次第に明らかにさ れつつある. 本論文では,補綴歯科が健康長寿に与えるインパクト について,介入研究を含めて優れた臨床研究のエビデン スから論じてみることにする.しかしながら,この分野 日補綴会誌 Ann Jpn Prosthodont Soc 4 : 397-402, 2012

To achieve greater recognition for prosthodontics in academia and among the general public as a vital health science specialty for the 21st century, and to advance this specialty's contributions to society, the Japan Prosthodontic Society has become a corporate juridical person. Today, our organization stands ready to accept the responsibility for leadership in developing initiatives to improve prosthodontic education, research, and treatment. This article examines the future prospects for our discipline in the context of current trends and prospects.

Purpose: The aim of this study is to present a new procedure in dental practice to prevent aspiration or ingestion of restorations; this procedure is economical and applicable to many kinds of indirect restoration materials.Methods: The jig comprises three rings in a line and bends at a right angle at the central ring. It is made of autopolymerizing acrylic resin that is molded with a self-made elastic mold. A 30-cm length of dental floss is tied to the ring at one side. The ring at the other side is glued with cyanoacrylate onto the non-occlusal surface of the restoration. If the ring does not properly fit the surface, a small amount of autopolymerizing resin may be brushed on it before gluing.Results: After ensuring that the jig is fixed firm enough, the operators can try-in, adjust, and retrieve the restoration without concerns regarding aspiration/ingestion. After cementation, the jig can easily be removed from the restoration by using scalers.Conclusion: This procedure allows us to decrease the risk of aspiration and ingestion of restorations in daily dental practice.

Purpose: This study was performed to clarify the possibility of bone regeneration with a cell-hybridized artificial bone by evaluating bone formation in the beagle dog femur.Methods: Bone marrow stromal cells (BMSCs) /interconnected porous hydroxyapatite (IP-CHA) composites as a cell-hybridized artificial bone were made by the injection of the BMSCs solution into IP-CHA. The distribution of BMSCs in IP-CHA was examined by scanning electron microscopy. Two BMSCs/IP-CHA composites (the BMSCs of one composite were labeled fluorescence) were placed into each of two bone sockets (φ3.7 mm×7 mm) prepared in the right femur of the beagle dog. After 4 weeks of surgery, new bone formation in the socket was examined by light microscopy and fluorescence microscopy.Results: SEM showed well distribution of the injected BMSCs in the pores of IP-CHA. At 4 weeks, new bone formation was detected at the cortical areas of the composites, and injected BMSCs were identified in the new bone area of the interconnected pores. Conclusion: The limited results of this study may suggest that BMSCs/IP-CHA composites as cell-hybridized artificial bone is a possible candidate for bone regeneration.

歯の喪失は, そこにいたるまでの問題のある食習慣や生活習慣などの結果としての病態であるといえる. その意味から, 無歯顎者は健康でなくなるリスクの高い人たちともいえる. また, 無歯顎という病態そのものが, 咀嚼障害や審美障害をもたらし, 社会的活動性を制限することから, より健康でなくなるリスクを高める可能性がある. これまでの報告から, 歯が20本以上もしくは16本以上残存している高齢者は, そうでない高齢者に比べて有意に長命であることが示されている. さらに, 義歯装着と生命予後との関係について, われわれが行った調査では, 上下顎で残存歯による咬合のない高齢者では, 義歯を装着していない者は装着している者に比べて1.52倍 (95%CI: 1.25-1.83) 有意に死亡率が高いことが示されている. このように, 歯や咬合の有無が生命予後に影響を及ぼす可能性が明らかになったことは, 今後われわれがなすべき研究のひとつの方向性を示しており, ここでは, 考えられるそのいくつかについて, 文献的考察ならびにわれわれの調査結果を含めて提示した. このような疫学的研究に基づいた仮説とその立証が, 超高齢社会における歯科補綴学の意義を明確にしていくうえで重要な取り組みの1つであると考える.

It has been well recognized that geriatric dentistry will become more important in the 21st century because of the increase of the elderly population and their longevity of life. Geriatric dentistry should tackle prevention, medication, and welfare as one. The main theme of prevention is health promotion to obtain high quality of life by maintaining their own teeth and occlusion. The purpose of medication is to enhance the quality of life by repairing masticatory function and esthetics. Moreover, dentists should take part in the care for the elderly with complex medical conditions through oral health care and rehabilitation of eating. Technology assessment is one of the most useful ways to examine the quality of medicine and quality of life. In this paper, technology assessment has been performed to evaluate complete denture treatment using our original scores. The subjects were classified into two groups, one group of 28 persons (12males, 16 females, mean age 71.5 years) who were treated by complete denture treatment at the university hospital and another group of 30 (13 males, 17 females, mean age 72.3 years) who were treated by complete denture treatment at private offices in Kure City. The complete denture score was obtained by examination of quality of medicine, the chewing function and satisfaction scores of complete denture prosthesis defined treatment outcome, and the QOL score was used to identify their own quality of life. As a result, complete denture score in the group at the university hospital was significantly higher than that in the other group. Significant relationship was detected between the complete denture and satisfaction scores (p

The purpose of this in vitro study was to evaluate the antimicrobial effects of tissue conditioners containing an antibiotic ceramic, silver-zeolite (ZM)(Zeomic® AJ 10N, Shinagawa Fuel Co., Nagoya, Japan). Five commercially available tissue conditioners were selected and specimens with ZM (2 wt%) was prepared. Tissue conditioners without ZM and plastic plate were used as a positive control and a negative control respectively. Staphylococcus aureus FDA 209 P, Pseudomonas aeruginosa KM 338 and Candida albicans IFO 1385 were selected as test bacteria. Bacterial suspension (approximately 106 cells) was poured onto the materials (plate-shaped, 10×10×5mm) and they were incubated at 37°C for 0, 24 and 48 hours. Then the number of viable bacteria in the suspension was counted as colony forming unit (CFU). These procedures were also carried out for the materials stored in artificial saliva for 1 week. No CFU of S. aureus, P. aeruginosa and C. albicans was detected on all ZM containing materials. Only S. aureus and C. albicans could form no colony on the positive control materials. Storage in artificial saliva showed no influence on antibiotic effects of these materials. These results indicate that ZM containing tissue conditioners have antimicrobial effects against not only S. aureus and C. albicans but also P. aeruginosa and these effects may persist in saliva.

The effect of the variation of the curvature of the cast circumferential clasp arm on clasp stiffness and stress was evaluated using three-dimensional finite element analysis.The results were as follows:1. The curvature of the clasp arm under the condition of different lengths affected stiffness and stress.1) The clasp arm using a non-tapered pattern with a small curvature showed less stiffness and lower stress than the arm with a large curvature.2) The clasp arms using the original patterns, which were established from our previous study (taper 0.8, T/W ratio: 1/2 or 1/3), showed constant stiffness and low stress instead of change of curvature.3) The clasp arm using Rapid flex pattern with large curvature showed lower stress than the arm with a small curvature.2. The clasp arm with an adequate curvature in the condition of the same length showed low stress. This seemed to be the effect of torsion elasticity which was regarded to distribute the stress in the clasp arm.

A new protocol for classifying of TM disorders was developed in order to classify the types of TM disorders followed by the criteria of Japanese Society for Temporomandibular Joint.This protocol consists of following several characteristics.1. It may be possible to shorten filling up time because of a filling up way of systematic procedure and selecting minimum items.2. It may be possible to classify TM disorders quickly because an instruction for filling up and a table for classifying the type of TM disorders are attached.3. It may be easy to evaluate the process of change of symptoms.4. It attaches a table of examination for finding differential diagnosis of TM disorders.5. It may be possible to fill up the results for various examinations of jaw function.6. It may be possible to use the construction of data base for the protocol for TM disorders by Japanese Society of Stomatognathic Function.

In order to establish a diagnostic system for temporomandibular (TM) disorder patients, data were collected on the mandibular border movement at incisal point from TM disorder patients and analized by multi valiable analysis comparing with data from the subjects with no TM disorder symptom.Seven parameters were identified as useful ones for the discrimination between TM disorder group and control group. With these parameters, 71% of TM disorder group and 91% of control group were correctly discriminated, respectively.These findings suggest that application of multi valiable analysis may be useful for a diagnosis of TM disorder patients.

An attempt was done to evaluate clinical figures in the first examination of mandibular dysfunction patients with two or more symptoms of temporomandibular joint (TMJ) pain, TMJ sounds and limitation of mandibular movement followed by no organic change in the TMJ. The results were as follows:1. A great prevalence of female was seen and the ratio of female/male was 9 to 1.2. In age distribution, the patients of 10 years old to 19 and 20 to 29 were predominant.3. Most patients were treated by restorative therapies and few of them had experiences of several general diseases.4. Evaluating the chief complaints associated with the first symptoms, TMJ pain was much predominant in comparison with TMJ sounds.5. Clinical symptoms were expressed by TMJ pain, TMJ sounds and limitation of mandibular movement with other symptoms as headache, neck and shoulder pain and ear symptoms.6. Most patients had natural dentitions. Premature contacts were seen in centric relation in all patients and more than half of them had occlusal interferences in eccentric relations.7. The remarkable presence of oppressive pains in masticatory muscles was observed. The finding that factors which might be associated with muscle tensions were seen in many patients suggest the correlation between mandibular dysfunction and muscle hyperactivity.

The clinical effect of full coverage occlusal splint during 13 weeks insertion was investigated in 30 mandibular dysfunction patients with two or more symptoms of temporomandibular joint (TMJ) pain, TMJ sounds and limitation of mandibular movement followed by no organic change in the TMJ, who were reported in part 1 of this study.A remarkable effect of occlusal splint was obtained and 86.7% of the 30 patients were improved totally. Especially, the symptoms, TMJ pain and shoulder stiffness were much improved, but less effective was seen to buccal pain and temporal headache. The period of producing the effect of occlusal splint was different to each symptom, but no change was seen after 10 weeks in any symptoms.These results clearly show the effect of full coverage occlusal splint for mandibular dysfunction patients and useful suggestion of occlusal splint therapy to this disease was obtained.

To clarify the dietary intake of full denture wearers, a hundred and ten wearers with upper and lower full denture were investigated by the questionnaire on the acceptability for chewing.The following results were obtained.1. The difficulty of chewing a hundred kinds of foods were determined numerically (0 to 100).2. A table including twenty kinds of foods for full denture wearers was set up to scorerize the chewing ability of each wearer.3. The score of chewing ability was well related to the acceptability for chewing function.