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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.

The objective of this study was to investigate how the connection of superstructures to implants with different surface properties affects the surrounding bone. The right and left mandibular premolars and molars of 5 dogs were extracted. After 12 weeks, a machined implant was placed mesially and an anodized implant was placed distally on one side of the edentulous jaw, with the positions reversed on the opposite side. Twelve weeks after implantation, splinted superstructures were set to the implants. At 24 weeks after implantation, the implant stability quotient (ISQ) was measured, radiographs were obtained. Removal torque values were measured and histologic observation was performed. The ISQ values at 24 weeks after implantation were not significantly different between the groups. The removal torque values were significantly different between the distal anodized and distal machined implants (p &lt, 0.05). From 12 to 24 weeks, marginal bone losses were not significantly different between the groups. Fluorescent observation of tissue samples revealed bone-remodeling activity around all of the implants. The results of this study suggest that when implants with different surface properties are connected, machined implants at the most distal sites might be a potential risk factor for implant-bone binding.

The aim of this multicentre prospective study was to investigate the effect of prosthetic restoration for missing posterior teeth in patients with shortened dental arches (SDAs). SDA patients with 2-12 missing occlusal units (a pair of occluding premolars corresponds to one unit, and a pair of occluding molars corresponds to two units) were consecutively recruited from seven university-based dental hospitals in Japan. Patients chose no replacement of missing teeth or prosthetic treatment with removable partial dentures (RPDs) or implant-supported fixed partial dentures (IFPDs). Oral health-related quality of life (OHRQoL) was measured using the oral health impact profile (Japanese version - OHIP-J) at baseline and follow-up/post-treatment evaluation. Of the 169 subjects who completed baseline evaluation, 125 subjects (mean age; 63.0 years) received follow-up/post-treatment evaluation. No-treatment was chosen by 42% (53/125) of the subjects, and 58% (72/125) chose treatment with a RPD (n = 53) or an IFPD (n = 19). In the no-treatment (NT) group, the mean OHIP summary score at baseline was similar to that at follow-up evaluation (P = 0.69). In the treatment (TRT) group, the mean OHIP summary score decreased significantly after the RPD treatment (P = 0.002), and it tended to decrease, though not statistically significant (P = 0.18), after the IFPD treatment. The restoration of one occlusal unit was associated with a 1.2-point decrease in OHIP summary score (P = 0.034). These results suggest that the replacement of missing posterior teeth with RPDs or IFPDs improved OHRQoL. Prosthetic restoration for SDAs may benefit OHRQoL in patients needing replacement of missing posterior teeth.

Evaluating primary stability is important to predict the prognosis of dental implant treatment. Primary stability is decreased in a low bone density site such as osteoporosis. However, it is difficult to apply in small animal and the effect of the different implant surface topography for the primary stability at low bone density site has not yet fully been investigated. The purpose of the present study was to evaluate the influence of implant surface topography on primary stability in a standardized osteoporosis animal model. Six rabbits underwent ovariectomy and administrated glucocorticoid to induce an osteoporosis model. Sham-operations were performed in additional six rabbits. Implants with machined or oxidized-surfaces were inserted into the femur epiphyses and insertion torque (IT) and implant stability quotient (ISQ) were measured. In sham model, the IT and ISQ did not differ significantly between the both implant. However, the IT value of oxidized-surface implant was significantly higher than that of the machined implant in the osteoporosis model. Meanwhile, ISQ did not significantly differ between the machined and oxidized-surfaced implants. In conclusion, the IT of implants is higher with rough than with smooth surfaces but that there are no differences in ISQ value between different surfaces in a standardized osteoporosis bone reduced rabbit model.

The aim of this study was to evaluate the stability of implant/interconnected porous calcium hydroxyapatite complex (implant/IPCHA-complex) under functional loading. Implant/IP-CHA-complexes were placed into the mandibles of four Beagle-Labrador hybrid dogs (complex-group). On the other side, an implant was placed directly (control-group). To subject the loading, the animals were fed a hard diet throughout the loading phase of 5 months. The implant stability quotients (ISQs) and bone implant contact (BIC), and histological evaluations were performed. The ISQs of implant/IP-CHA-complex was significantly lower at placement than that of the control-implant. On the other hand, there was no significant difference between in the groups during loading. The BIC measurements, there was no significantly difference between in both groups. Histologically, newly formed bone was observed in contact with most of the implant surface in the complex-group. An IP-CHA/implant-complex would be able to achieve both bone reconstruction and implant stability under functional loading conditions.

Background and objective Previous studies have reported that tooth loss is a risk factor of Alzheimer's disease (AD). However, the association between tooth loss and cognition and the impact of tooth loss on the molecular pathogenesis of AD remain elusive. In this study, we tested the effect of tooth loss on learning and memory and on the molecular pathogenesis of AD in an aged AD model mice. Materials and methods We divided 14-month-old amyloid precursor protein (APP) transgenic mice, an AD model mouse line, into upper molar extracted group (experimental) and molar intact group (control). At 18 months old, we analysed not only the changes of amyloid-beta (Aβ), pyramidal cells in the brain but also the learning and memory ability with step-through passive avoidance test. Results The amount of Aβ and the number of pyramidal cells in the hippocampus were not significantly different between the experimental and control group. Similarly, the difference of learning and memory ability could not be distinguished between the groups. Conclusion Neither molecular pathogenesis of AD nor associated learning and memory were aggravated by tooth loss in these mice. The limited results of this study which used the aged mice may help the dental profession to plan and explain treatments to patients with AD, which must be designed while taking into account the severity of the AD symptoms.

The implant stability quotient (ISQ) has been widely evaluated in clinical studies and animal experiments. However, accurate measurement is often difficult in animal models. In such cases, measurement of ISQ in bone is needed after formalin fixation. However, it is not yet clear how such fixation influences the measurement. The purpose of this study was to investigate the influence of formalin fixation on ISQ and the mechanical characteristics of bone. Fourteen tibias were harvested from rabbits; the samples from the left (length 60mm, control group) were soaked in saline and the samples from the right (length 60mm, fixation group) were fixed in 10% neutral-buffered formalin at 4°C for 4h. Three-point bending tests were done at 5mm/min to measure the maximum load and total absorbed energy. Twelve titanium implants (Brånemark System(®) Mk-III TiUnite, Nobel Biocare, Sweden) were placed into the edentulous molar site of the mandibles of 2 dogs and the ISQ was measured by Osstell(®) (control group) 3 months later. The implants involved in the bone block were then fixed for 4h (fixation group) and the ISQ measured. The maximum load values did not differ significantly between the control and fixation groups. Total absorbed energy was significantly higher in the control group than in the fixation group. ISQ did not differ significantly between the groups. These results suggest that formalin fixation of bone might affect some of the mechanical characteristics of bone, but not its ISQ.

Tooth loss is a known risk factor of Alzheimer's disease (AD). However, the association of tooth loss with the molecular pathogenesis of AD is still unknown. The hypothesis that the molecular pathogenesis of AD is enhanced by molar tooth loss was tested. Seventeen female transgenic mice (J20) were divided into the experimental (EX, n=10) and control (C, n=7) groups. In the EX group, maxillary bilateral molar teeth were extracted at the age of 6 months. In the C group, however, these teeth remained intact. Passive avoidance test was performed to evaluate learning and memory abilities right after tooth extraction (6 months old) and 4 months later (10 months old). After the test at 10 months, amyloid beta (Aβ) deposition and changes of neuronal cell number and area in the hippocampus were investigated using half of the brains. The other half was homogenized and used to determine Aβ40 and Aβ42 levels by ELISA. At the 10 months of age, learning and memory abilities were significantly impaired in the EX group compared to the C group (P

Carbonate apatite-chitosan scaffolds (CA-ChSs) were fabricated using the lyophilization technique. It was found that ChSs prepared with 200 mg chitosan powder (ChSs200) had well-structured three-dimensional architecture with high porosity and good retentive form without brittleness. In addition, it was shown that the number of osteoblast-like cells MC3T3-E1 proliferated on desalinated ChSs200 was larger than that on the non-desalinated ChSs200. CA-ChSs were fabricated by adding 100 mg carbonate apatite (CA) to 200 mg chitosan gels followed by freeze-drying (CA100ChSs200). SEM observation revealed that CA100ChSs200 had favorable three- dimensional porous structures. The number of living cells increased more rapidly on CA100ChSs200 prepared with different amounts of CA than on ChSs. ALP activity significantly increased after day 14 and reached a plateau after day 21 in ChSs200 and CA100ChSs200. It was concluded that newly developed CA100ChSs200 may be a possible scaffold material for tissue engineering.

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.

The Japan Prosthodontic Society developed a multi-axis assessment protocol to evaluate the complex variations in patients who need prosthodontic care, and to classify the level of treatment difficulty. A previous report found the protocol to be sufficiently reliable. The purpose of this multi-center cohort study was to evaluate the validity of this multi-axis assessment protocol.The treatment difficulty was evaluated using the multi-axis assessment protocol before starting prosthodontic treatment. The time required for active prosthodontic treatment, medical resources such as treatment cost, and changes in the oral health-related QOL before and after treatment, were evaluated after treatment completion. The construct validity of this protocol was assessed by the correlation between the dentist's pre-operative subjective assessment of the treatment difficulty, and the level of difficulty determined by this protocol. The predictive validity was assessed estimating the correlations between a "comprehensive level of treatment difficulty" based on the four axes of this protocol and total treatment cost, total treatment time, and changes in the oral health-related QOL before and after treatment.The construct validity of this protocol was well documented except for psychological assessment. Regarding the predictive validity, the comprehensive level of treatment difficulty assessed before treatment was significantly correlated with the three surrogate endpoints known to be related to the treatment difficulty (total treatment cost, treatment time, and improvement in the oral health-related QOL). To further clarify the validity of the protocol according to patients' oral condition, a subgroup analysis by defects was performed. Analyses revealed that treatment difficulty assessment before treatment was significantly related to one or two surrogate endpoints in the fully edentulous patients and the partially edentulous patients. No significant relationship was observed in the patients with mixture of full/partial edentulism and the patients with teeth problems, possibly due to the small sample size in these groups.This study revealed that the multi-axis assessment protocol was sufficiently valid to predict the level of treatment difficulty in prosthodontic care in patients with fully edentulous defects and with partially edentulous defects.

The aim of this multicentre study was to investigate the effect of prosthetic restoration for missing posterior teeth on mastication in patients with shortened dental arches (SDAs). Partially dentate patients who had an intact teeth in anterior region and missed distal molar(s) (2-12 missing occlusal units) classified as Kennedy Class I or Class II were recruited from seven university-based dental hospitals in Japan. Of the 125 subjects who underwent baseline (pre-treatment) and follow-up/post-treatment evaluation, 53 chose no replacement of missing teeth and 72 chose treatment with removable partial dentures (n = 53) or implant-supported fixed partial dentures (n = 19). Objective masticatory performance (MP) was evaluated using a gummy jelly test. Perception of chewing ability (CA) was rated using a food intake questionnaire. In the no-treatment group, mean MP and CA scores at baseline were similar to those at follow-up evaluation (P0·05). In the treatment group, mean MP after treatment was significantly greater than the pre-treatment mean MP (P0·05). However, the mean perceived CA in the treatment groups was similar at pre- and post-treatment (P0·05). In a subgroup analysis of subjects in the treatment group, subjects with lower pre-treatment CA showed a significant CA increase after treatment (P = 0·004), but those with higher pre-treatment CA showed a significant decrease in CA (P = 0·001). These results suggest that prosthetic restoration for SDAs may benefit objective masticatory performance in patients needing replacement of missing posterior teeth, but the benefit in subjective chewing ability seems to be limited in subjects with perceived impairment in chewing ability before treatment.

doi: 10.1111/j.1741-2358.2012.00664.x Relationship between behavioral and psychological symptoms of dementia and oral health status in the elderly with vascular dementia Objectives: The aim of this study was to clarify the relationship between behavioral and psychological symptoms of dementia (BPSD) and oral status in the elderly with vascular dementia. Background: There have been some reports of a relationship between disease symptoms and oral status in the elderly with Alzheimer’s disease, but few reports have been conducted in the elderly with vascular dementia. Until now, the relationship between BPSD and oral status has been unknown. Materials and methods: An investigation was conducted concerning BPSD and oral status among 57 subjects with vascular dementia (mean age, 85.7 ± 5.5 years). The wearing of dentures and oral activities of daily living (oral ADL) were examined. Results: Subjects with activity disturbances and those with aggressiveness had significantly lower rates of denture wearing than those without these two symptoms (p

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.

doi: 10.1111/j.1741-2358.2011.00615.x Maximal voluntary tongue pressure is decreased in Japanese frail elderly persons Background and objective: To quantitatively estimate tongue function, we developed a handy device for intraoral pressure measurement. The objective of this study was to assess maximum voluntary tongue pressure (MVTP) in Japanese frail elderly persons receiving nursing care services. Materials and methods: The study included 42 men and 87 women, aged 58–100 years. To record MVTP, the participants were asked to compress the balloon (diameter: 18 mm) of the disposable intraoral pressure probe onto their palates for 7 s using the maximum voluntary effort of the tongue. Pressures were recorded three times at 1 min intervals. Results: Maximum voluntary tongue pressure was successfully measured in 111 persons. Mean (standard deviation) MVTP was 18 (12) kPa, with a range of 0–63 kPa. The remaining 18 persons could not accurately follow our instructions and MVTP could not be measured. Conclusion: In comparison with the reported standard value using the same device, the frail elderly persons included in our study were found to exert less MVTP than healthy dentate individuals. These results suggest the need for proper quantitative evaluation of oral function, including tongue capacity, at nursing care facilities.

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

The purpose of this study was to investigate the use of different plasticizers in soft acrylic resin materials to reduce leaching of the plasticizer and thus increase the durability of tissue conditioners. Samples were prepared containing different combinations of three types of polymer/copolymer powder and four types of plasticizer liquid (DEHM, DIBA, DAA and DINA). The dynamic viscoelasticity of each sample was measured after water immersion using a dynamic mechanical analyzer. Water absorption, solubility and weight change were also measured. A significant difference was found among the materials regarding dynamic viscoelasticity, water absorption and solubility. The samples containing P-n-BMA had the most stable G' and G'' scores throughout the immersion. P-n-BMA is the most suitable powder together with DEHM as the most suitable liquid component for a tissue conditioner. These results suggest that it is possible to improve the durability of tissue conditioners by combining different polymers and plasticizers.

The purpose of this study was to evaluate preoperative CT-derived bone densities in Hounsfield units (HU) at implant sites that acquired primary stability, and to compare these values to the optimal bone densities proposed in the literature. Fifty-one patients, 18 males (37 implant sites) and 33 females (67 implant sites) between 2003 and 2010 were assessed. CT data for different jaw sections, regions, and operating procedures were compared using the Kruskal-Wallis test and Scheffe's test for multiple comparisons (P<0.05). The mean bone density in the maxilla was significantly lower than that in the mandible (P<0.05); the mean bone densities in the 4 jaw regions decreased in the following order: anterior mandible > anterior maxilla > posterior mandible > posterior maxilla. The bone densities assessed by HU fell into the range of optimal bone densities associated with acquired primary implant stability proposed in the literature.

doi: 10.1111/j.1741-2358.2011.00555.x Nutritional status and oral status of the elderly with dementia: a 2-year study Objectives: To determine the relationship between denture wearing and nutritional status in the elderly with dementia. Background: There could be a correlation between nutrition, oral health, dietary habits, patients’ satisfaction, and their socio-economic status in the elderly, and the relationship between compromised oral status and nutritional status in the elderly with dementia. Subjects and methods: A 2-year follow-up study of 63 elderly Japanese women with and without dentures from a nursing home was undertaken to investigate their oral, physical and mental, and nutritional status. Results: Each item for 2006 and 2008 in this study showed no significant difference between 2006 and 2008, except the calories/day. The elderly with dementia without complete dentures during the 2 years of the study only significantly decreased the mean of the calories/day. Conclusion: The calories/day of the elderly with dementia without dentures decreased after 2 years. Denture wearing for the elderly with dementia could be necessary to maintain a satisfactory intake of calories.

doi: 10.1111/j.1741-2358.2011.00505.x The evaluation of oral health in stroke patients Objective: As tooth loss has been suggested as a potential risk factor for stroke, oral examinations were carried out on stroke patients to review the oral condition of those patients. Method: The subjects were patients consecutively discharged from the recovery rehabilitation unit of Hiroshima City General Rehabilitation Center between April 2008 and December 2009. All patients were offered oral examination and 358 of 443 patients accepted. Patients receiving dental examination were divided into two groups: one group comprising stroke patients and the second, patients with other disorders. These two groups were then compared for the number of remaining teeth by age group. Results: Among the examined patients, the number of remaining teeth in stroke patients in their 50s and 60s was significantly lower than for patients in corresponding age groups (18.4 ± 9.4 vs. 24.5 ± 5.4 and 18.3 ± 9.2 vs. 22.2 ± 7.2, respectively, with p

Summary Tongue pressure measured with a disposable hand-held balloon probe has been used for assessing tongue function; however, no diagnostic standard for assessing other oral functions exists currently. In this study, to develop a method for multifactorial manometric evaluation of oral functions, 20 men and 20 women (21–32 years of age) were instructed to apply 7-s maximal voluntary muscular effort on a hand-held balloon probe placed against the anterior and lateral parts of the palate, buccal surface of the molars on the habitual chewing side and labial surface of the anterior teeth for measuring anterior and posterior tongue, cheek and lip pressures (LPs), respectively. Intra-session reproducibility was determined by three repeated measurements, and associations between the obtained and the conventional data on oral diadochokinesis were tested. The men exhibited higher values of all the pressure types. Further, both genders showed a positive correlation between anterior and posterior tongue pressures (PTPs) (P

Aim: The purpose of this study was to clarify the correlation between dental and nutritional status among community-dwelling elderly Japanese people. Methods: The subjects were 182 elderly individuals, aged 65–85 years, who voluntarily participated in a health seminar at Kyoto Prefectural University of Medicine. These subjects were divided into two groups according to the occlusion. The subjects in the retained contact group were those who had retained molar occlusion with natural teeth. The lost contact group were those who retained molar occlusion with removable partial dentures. Anthropometric variables such as body mass index (BMI) were collected and dietary intake was assessed using a brief self-administered diet history questionnaire (BDHQ). Results: No statistical difference in BMI or intake of macronutrients was found between these two occlusal groups. The lost contact group reported significantly lower consumption of vegetables and higher consumption of confectionaries (foods rich in sugar) than did the retained contact group (P

The purpose of this study was to measure the time-dependent chemical interaction between synthetic RGDS(PO(3)H(2))PA (P-RGD) peptide and titanium surfaces using a titanium surface plasmon resonance (SPR) biosensor and to determine the degree of peptide immobilization on the surfaces. An SPR instrument for 'single-spot' analysis was used for nanometer-scale detection of biomolecular adsorption using a He-Ne laser light according to Knoll's method. The oxidized titanium surface was etched when exposed to H(3)PO(4) solutions with a pH of 2.0 or below. The amount of P-RGD adsorbed at pH 1.9 was approximately 3.6 times as much as that at pH 3.0 (P < 0.05). P-RGD naturally adsorbed on the oxidized titanium surface as a consequence of the bonding and dissociation mechanism of the phosphate functional group. Furthermore, the control of pH played a very important role in the interaction between P-RGD and the surface. These findings show that pH control may promote progressive binding of biomolecules with the phosphate functional group to the titanium surface.

The objective of this study was to examine the association between sleep bruxism and psychological stress. The subjects consisted of 76 volunteers, who were divided into those with and without bruxism according to the diagnostic criteria for sleep bruxism outlined by the American Academy of Sleep Medicine (AASM). Stress sensitivity was evaluated before and after an experimental stress task, which involved simple mathematical calculations. It was assessed objectively by measuring the subjects' salivary chromogranin A (CgA) levels and subjectively using a ten-division visual analog scale (VAS). Compared with those observed before the stress task, the mean salivary CgA levels of the non-bruxism group (n = 54) were not significantly increased after the stress task. Conversely, the mean salivary CgA levels of the bruxism group (n = 22) were significantly increased after the stress task (P < 0.01). The mean VAS scores of the groups without (n = 54) and with (n = 22) bruxism were significantly (P < 0.01) increased after the stress task compared with those observed before the stress task, but no differences were detected between the two groups in the stress task. These findings suggest that there is an association between sleep bruxism and psychological stress sensitivity.

The aim of this study was to identify the factors related to prosthetic restoration in patients with shortened dental arches (SDA). SDA patients with 2-12 missing occlusal units were consecutively enrolled from seven university-based dental hospitals in Japan. Of the 145 subjects (mean age; 63·4 years), 41% chose no treatment and 59% sought to replace their edentulous spaces with removable partial dentures or implant-supported fixed partial dentures. Restoration decisions were related to tooth loss patterns. Only 3% of subjects missing just second molar(s) sought to receive prosthetic treatment, while the percentage increased to 58% in subjects who were missing first and second molars and 93% in subjects missing premolar(s). Logistic regression analyses found that young age, increased number of missing occlusal units, asymmetric arch and presence of chewing complaint were significant predictors for prosthetic restoration (P

Objectives: The aim of this study was to examine the relation between the degree of tongue-coating and oral function. Background: Tongue-coating is a moss-like deposit which forms over the tongue surface, and includes micro-organisms, food residues, and abrasive epithelia. It is considered that motor function of the tongue and lips and saliva secretion decrease in the aged and have some effect on the accumulation of tongue-coating. Although saliva secretion has been reported as a factor amongst these oral functions in contributing to tongue-coating, the correlation with the motor function of oral structures is unknown. Subjects and methods: The factors that contribute to the accumulation of tongue-coating were examined in 48 subjects of advanced age (mean age 80.8 ± 7.8 years) with no severe levels of periodontal disease. Changes in the degree of tongue-coating were also examined after oral functional training in these subjects. The frequency of oral cleaning, status of oral hygiene, motor function of the tongue, and masticatory performance were examined as potential factors associated with the degree of coating. Results: The results showed that tongue pressure and the frequency of oral diadochokinesis measured by pronouncing the single syllable ‘ka’ as an indicator were statistically significantly correlated with the degree of tongue-coating. Several factors in oral function improved with training, and also the degree of tongue-coating decreased in 27 subjects. Conclusion: These results suggest a correlation between the degree of tongue-coating and a reduction in lingual motor function and, in addition, possible improvement in level of coating by functional training of the tongue.

– Objectives: An important purpose of denture treatment is the improvement of nutritional intake. This is especially important for the dependent elderly who have a high risk of protein-energy malnutrition. To evaluate the impact of denture treatment on such a population, we compared body weight as an indicator of nutritional status before and 6 months after prosthodontic treatment. Methods: This study was conducted in a long-term care geriatric hospital in Hiroshima, Japan from October 2004 to September 2006. One hundred and four patients received complete or partial denture treatment in both jaws. Nineteen patients were lost to the study because of the development of severe physical conditions or death. Among the remaining 85 patients, 66 used their new prostheses and 19 did not. Body weight and serum albumin levels were examined at prosthesis insertion and 6 months after treatment. Results: Six months after prosthodontic treatment body weight changes were significantly different between users and non-users regardless of denture type and, in addition, serum albumin level were significantly increased among individuals using partial denture in either or both jaws (P

Basic fibroblast growth factor (bFGF) and inorganic polyphosphate (poly(P)) have been recognized as therapeutic agents that enhance bone regeneration. It has also been shown that poly(P) may enhance the mitogenic activity of bFGF. The purpose of this study is to evaluate the combined effect of bFGF and poly(P) on bioactivities of osteoblasts and initial bone regeneration in vitro and in vivo. MC3T3-E1 cells were treated with bFGF, poly(P) or bFGF+poly(P), then subjected to cell proliferation assay, alkaline phosphatase (ALP) activity measurement, quantitative real-time reverse transcription-polymerase chain reaction and Alizarin S Red staining. In an in vivo study, bFGF-, poly(P)- and bFGF+poly(P)-modified interconnected porous hydroxyapatite (IPHA) complexes were fabricated, and placed into the femurs of rabbits to evaluate new bone formation histologically and histomorphometrically. The highest enhancement of cell proliferation were observed in those treated with bFGF+poly(P) on days 5 and 7. Cells treated with bFGF+poly(P) also exhibited increased ALP activity on days 5 and 10, up-regulated mRNA levels of osteocalcin and osteopontin, and enhanced calcification when compared to the non-treated cells. In vivo, the highest bone formation ratio was observed in bFGF+poly(P)-modified IPHA complexes. This study indicated that co-application of bFGF and poly(P) may provide enhanced bone formation by modulating cell proliferation and the mineralization process. It is anticipated that a combined application of bFGF and poly(P) can provide a novel method for bone regeneration in clinical use.

Hydroxyapatite and carbonate apatites with different carbonate contents were synthesized, mixed with atelocollagen, and made into sponge scaffolds. The scaffolds were implanted into the bone sockets of the femurs of male New Zealand white rabbits for 2, 3, 12 and 24 weeks. carbonate apatite-collagen scaffold with 4.8 wt% carbonate content appeared to have similar crystallinity and chemical composition to human bone. When the scaffolds were implanted into the rabbit femurs, histological observation indicated that the carbonate apatites-collagen scaffolds with relatively higher carbonate contents were gradually deformed throughout the implantation period, and showed uniform surrounding bone after 24 weeks and could not be distinguished. The carbonate apatite-collagen scaffold with 4.8 wt% carbonate content showed the highest bone area ratio of all of the scaffolds. It is suggested that a carbonate apatite-collagen scaffold with carbonate content similar to that of human bone may have optimal bone formation ability.

The aim of this study was to explore the relationship between patterns of missing occlusal units (OUs) and oral health-related quality of life (OHRQoL) in subjects with the shortened dental arches (SDAs). Subjects with SDAs were recruited consecutively for 1 month from six university-based prosthodontic clinics. In total, 115 SDA subjects participated (mean age, 58.5 +/- 10.0 years; 71% female). The location and number of missing teeth were examined and the number of missing OUs was calculated. To evaluate OHRQoL, the Japanese version of the Oral Health Impact Profile (OHIP-J) was administered and the summary score of OHIP-J was calculated. The SDA subjects were categorized depending upon the anterior-posterior lengths of the missing or remaining OUs. Regression analyses were performed to investigate the OHIP-J differences between groups of subjects with various anterior-posterior SDA lengths. The analyses revealed that subjects who only lost the second molar contact exhibited significantly better OHRQoL than those who lost more teeth [coefficient: 11.1, 95% confidence interval (CI): 2.8-19.2, P = 0.02]. Furthermore a statistically significant group difference was observed between the groups with and without the first molar occlusal contact (coefficient: 12.8, 95% CI: 1.4 to 24.1, P = 0.03). In conclusion, although our results are of exploratory nature and need validation, patterns of missing OUs are likely to be related to the OHRQoL impairment in SDA subjects with the presence of first molar contact having a particularly important role.

Although cyclic ADP-ribose (cADPR), a novel Ca2+-mobilizing mediator, is suggested to be involved in the functions of neutrophils in rodents, its role in human neutrophils remains unclear. The present study examined the ability of cADPR to mobilize Ca2+and mediate formyl methionyl leucyl phenylalanine (fMLP)-stimulated increase in cytosolic free Ca2+concentration ([Ca2+]i) and migration in human neutrophils. cADPR induced Ca2+release from digitonin-permeabilized neutrophils, and the release was blocked by 8Br-cADPR, an antagonist of cADPR. Immunophilin ligands, FK506 and rapamycin, but not cyclosporine A, inhibited cADPR-induced Ca2+release. 8Br-cADPR partially reduced fMLP-induced [Ca2+]irise and abolished the rise in combination with 2APB, an IP3-receptor antagonist. Anti-CD38Ab and NADase that interfere with cADPR formation, reduced the fMLP-induced [Ca2+]irise. When β-NAD+, a substrate of ADP-ribosyl cyclase, and cADPR were added to the medium, the former gradually increased [Ca2+]iand the latter potentiated the fMLP-induced [Ca2+]irise. The β-NAD+–induced [Ca2+]irise in Ca2+-free medium was inhibited by anti-CD38Ab, 8Br-cADPR, FK506, ruthenium red, and thapsigargin. mRNAs of nucleoside transporter (NT), ENT1, ENT2, CNT, and CNT3 were expressed in neutrophils; and their inhibitors, inosine, uridine, and s-(4-nitrobenzyl)-6-thioinosine, reduced the [Ca2+]irise induced by β-NAD+and fMLP. fMLP-stimulated migration was inhibited by the removal of Ca2+from the medium or by the addition of 8Br-cADPR, anti-CD38Ab, NADase, and NT inhibitors. These results suggest that cADPR was synthesized extracellularly by CD38, transported into the cells through NTs, and then Ca2+was mobilized by FK506-binding protein–dependent process. This process may be involved in fMLP-induced intracellular Ca2+signaling and migration in human neutrophils. Keywords:: cyclic ADP-ribose (cADPR), FK506-binding protein (FKBP), cytosolic Ca2+dynamics, nucleoside transporter, migration

Objective: To investigate the influence of maximal bite force, maximal tongue pressure, number of mastications and swallowing on the oro-pharyngeal residue in the elderly. Background: Oro-pharyngeal residue in the elderly is an indication of dysphagia. Pharyngeal residue is especially critical as it may cause aspiration pneumonia, which is one of the major causes of death in elderly. Materials and methods: Videofluorographic recordings were performed on 14 elderly volunteers (six males, eight females, age range 65–93 years) without any history or symptoms of dysphagia. The subjects were instructed to consume 9 g of barium containing bread in two manners; free mastication and swallow (FMS: masticate and swallow freely), and limited mastication and swallow (LMS: swallow once after 30 chewing actions). The amount of oral and pharyngeal residue was evaluated using a 4-point rating scale. Maximal occlusal force was measured by a pressure sensitive sheet, and maximal tongue pressure using a handy probe. Multiple regression analysis was performed to examine the influence of these items on the amount of oral and pharyngeal residue in FMS and LMS. Results: In FMS, age was found to be a factor which increased oral residue (p = 0.053), and the number of swallowing (p = 0.017) and the state of the prosthesis (p = 0.030) reduced the pharyngeal residue. In LMS, tongue pressure was a factor which reduced oral residue (p = 0.015) and increased pharyngeal residue (p = 0.008). Conclusion: It is suggested that in the elderly tongue pressure contributed to propulsion of the food bolus from oral cavity into the pharynx, and multiple swallowing contributed to the reduction in the amount of pharyngeal residue.

Objective: The present study compared surface electromyographic (sEMG) activity obtained from the submental muscle group for a tongue press and a head lift exercise as potential therapeutic exercises for dysphagic elderly. Materials and methods: Fifty-three healthy volunteers with a mean age of 35.3 participated in this study. Subjects were required to perform an isometric task, pressing their tongue against the hard palate, and an isotonic task requiring sustained lingual force against the hard palate. Pressure sensors were used to measure the amount of lingual pressure against the hard palate. Submental sEMG data from these tasks were compared with those obtained from the isometric and isotonic aspects of a head lift exercise. Results: No sEMG differences were identified between the isometric tongue press task and head lift exercise. Isotonic tongue press exercises resulted in significantly higher maximum and mean sEMG values compared with the isotonic head lift exercise (p

The purpose of this study was to investigate the chemical interaction between titanium implant surface and amino acids. Pure titanium disks were pretreated with 10 N HCl and ultrapure water at room temperature for 30 minutes each. Disks were then modified with one of the three amino acids--L-aspartic acid, L-serine, or L-threonine--at 37 degrees C for 12 hours. Modification with oxalic acid was used as a control. By means of X-ray photoelectron spectroscopy (XPS), amino acid powders and the modified surfaces without or with ultrasonic water rinsing were chemically analyzed. It was revealed that the N 1s peak which originated from amino acids was not or hardly detected in the wide scan spectra of amino acid-modified surfaces. Moreover, the COO- peak which originated from oxalic acid could hardly be detected in the narrow scan spectrum of the C is region of oxalic acid-modified surface with ultrasonic water rinsing. Based on the results of this study, it was concluded that amino acids could not chemically bond to the titanium surface.

Background: Inadequate dentition for mastication is one of the major issues associated with systemic health for institutionalized elderly people, but its prognostic value and related deaths have not been fully examined. Methods: Four hundred and three patients aged 65 and older were recruited from nine nursing homes and were prospectively followed up for morbidity and mortality for 5 years in Japan. These patients were classified into three groups according to dental status: patients who had adequate dentition with natural teeth only or natural teeth with partial dentures (Group A); those who were edentulous but wearing full dentures (Group B); and those who had inadequate dentition without dentures (Group C). Results: Dental status was strongly related to age, cognitive function and activities of daily living. After allowing for confounding effects, the 2-year risk of mortality among those in Group C was 1.84 times that of Group A (95% confidence interval 1.01–3.36, P = 0.047). Furthermore, the 5-year mortality rate in Group C was higher than that in Group A, whereas that was not significant with a hazard ratio of 1.30 (0.90–1.88, P = 0.168). The main causes of death were respiratory infections, which explained 14.1% of all causes of death in Group A, 14.3% in Group B and 18.3% in Group C. Any associations between a specific cause of death and the different dental status did not reach a significant level. Conclusion: Inadequate dental status is associated with high overall mortality. Our findings suggest that systemic attention to dental status should be recommended in institutionalized elderly people.

OBJECTIVES: To clarify the influence of aging and denture use on swallowing in healthy edentulous people aged 75 and older. DESIGN: A cross-sectional research design was used with participants from Hiroshima University Hospital, Hiroshima University, and Hiroshima City. SETTING: Participants were examined in Hiroshima University Hospital, Hiroshima, Japan. PARTICIPANTS: Thirteen edentulous elderly volunteers (7 male, 6 female; aged 75–86, mean age 81.2) and 19 dentulous elderly volunteers (12 male, 7 female; aged 80–87, mean age 81.2) as a control group participated in this study. Participants reported no clinical symptoms relating to dysphagia, neurological impairments, or degenerative diseases. MEASUREMENTS: Participants were asked to swallow a 10-mL barium sulfate solution three times. Edentulous older people were asked to swallow the solution while wearing dentures and with dentures removed. Functional swallowing was recorded on cine-film with a digital subtraction angiography system. Lateral cinefluorography images were obtained from seated subjects. Using a cine-projector, visual images were evaluated qualitatively and quantitatively. RESULTS: No participants exhibited aspiration. The occurrence of laryngeal penetration in the edentulous older people not wearing dentures was the only significant difference (P