Effectiveness of Communication Studies Program at Tokyo Dental College Based on Comments from Members of Public in Educational Organization.

The purpose of this study was to investigate the effectiveness of the Communication Studies Program at Tokyo Dental College as a tool in behavioral education. The number of Patient Community members who had participated in multiple sets of the program for third-year students in the same year within the 3-year period spanning 2016 to 2018 (152, 148, and 129 students in 2016, 2017, and 2018 respectively), and the period during which they had participated in multiple sets were investigated. Comments on student behavior, including on hairstyle, clothes, and attitude, were also analyzed. The total number of members who had participated in multiple sets (1 set comprised 1 lecture and 2 training sessions) was 5; and their comments were more favorable during the second (sets 3 and 4) than the first half of the 1-month program (sets 1 and 2). During the first half, the students were criticized for speaking softly, having bad posture, not concentrating, and having an attitude inappropriate for a medical worker; but in the second half, they were praised for beginning to adopt the proper attitude for a medical worker, speaking louder, having better posture, and a very serious attitude. These findings suggest that the Communication Studies Program is effective in improving student behavior.

Development of an oral health-related self-efficacy scale for use with older adults.

AIM: Self-efficacy is considered to be an important factor influencing behavior change; however, there are no existing tools to measure self-efficacy in the context of oral health among older adults. The purpose of the present study was to develop the Geriatric Self-Efficacy Scale for Oral Health (GSEOH) for use with older adults, and to evaluate its reliability and validity. METHODS: The self-administered questionnaire was completed by 646 Japanese older people. The draft version of the scale consisted of 35 items that were generated to measure the three dimensions of personal beliefs in tooth brushing, observing own oral health status and oral function. We carried out a principal components factor analysis with promax rotation, and investigated the scale's internal consistency and construct validity. RESULTS: The final version of the scale consisted of three dimensions measured with 20 items. Cronbach's alpha of the GSEOH total scale was 0.924. There were significant differences (P < 0.05) in total scores on the GSEOH for the change process of oral health behavior, and in relation to self-rated oral health. CONCLUSIONS: We developed the GSEOH, with three factors and 20 items, and confirmed its reliability and validity. More studies are necessary to investigate the cross-cultural validity and reliability with larger samples from other countries. Geriatr Gerontol Int 2017; 17: 1406-1411.

Prevalence and factors associated with xerostomia and hyposalivation among community-dwelling older people in Japan.

OBJECTIVE: This study investigated the prevalence and factors associated with xerostomia and hyposalivation among community-dwelling older people. BACKGROUND: Xerostomia and hyposalivation are common symptoms in the older population. MATERIALS AND METHODS: This study included with 894 community-dwelling, Japanese older people (355 men, 539 women; age 65-84 years) who participated in a comprehensive geriatric health examination, which included questionnaires and interviews regarding medical history, medications, Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC), depressive condition. The Zung Self-Rating Depression Scale (SDS) was used to evaluate depression. Resting salivary flow rate was evaluated by the modified cotton roll method. RESULTS: In this study, 34.8% of the participants (mean age, 73.5 ± 5.0 years) complained about xerostomia, while the prevalence of hyposalivation was 11.5%. Multiple regression analysis revealed hypnotics use [odds ratio (OR) = 1.71, 95% confidence interval (CI) = 1.13-2.61], SDS (OR = 1.05, CI = 1.04-1.07) and TMIG-IC total points (OR = 0.87, CI = 0.76-0.99) to be significantly associated with xerostomia. In contrast, female gender (OR = 2.59, CI = 1.55-4.31) and the use of agents affecting digestive organs (OR = 1.78, CI = 1.11-2.86) were associated with hyposalivation. CONCLUSION: Our findings showed that the prevalence of xerostomia and hyposalivation were approximately 1 in 3 and 1 in 10 respectively. The factors associated with psychological factors and high-level functional competence, while hyposalivation was associated with medications and gender, as well as systemic and/or metabolic differences. It is important to consider these multidimensional factors associated with xerostomia and hyposalivation.

Factors associated with self-rated oral health among community-dwelling older Japanese: A cross-sectional study.

OBJECTIVES: A cross-sectional study was carried out to investigate the determinants of self-rated oral health among community-dwelling older people in Japan. METHODS: The participants were 897 (357 men and 540 women) aged 65 years and over who participated in a comprehensive geriatric health examination, which included an oral examination, a face-to-face interview assessing cognitive function, questionnaires regarding depressive symptoms and functional capacity, and a medical examination. The oral examination measured indices of oral health status: number of present teeth, number of functional teeth, occlusal force and amount of resting saliva. Multiple logistic regression analyses were carried out to determine the factors associated with poor self-rated oral health. RESULTS: The mean age of the participants was 73.5 ± 5.0 years. The prevalence of poor and rather poor self-rated oral health was 11.5% and 29.5%, respectively. Multiple logistic regression analyses showed that the number of present teeth (odds ratio [OR] 0.97, 95% confidence intervals [CI] 0.95-0.99), difficulty in mastication (OR 3.20, CI 2.18-4.70), presence of xerostomia (OR 1.43, CI 1.02-2.01), total score on the MoCA-J (OR 1.06, CI 1.01-1.11), and reduction in frequency of leaving the house (OR 1.64, CI 1.12-2.41) were significantly associated with poor self-rated oral health. CONCLUSIONS: The present results suggested that self-rated oral health was a significant factor in oral health status as well as overall well-being among community-dwelling older Japanese people.

Effectiveness of an oral health educational program on community-dwelling older people with xerostomia.

AIM: The purpose of the present study was to evaluate the changes in oral health and function through an oral health educational program for the independent older people with xerostomia. METHODS: Community-dwelling older people with xerostomia aged over 65 years who participated in a preliminary comprehensive health survey in 2011 were recruited for the educational program. A total of 47 participants were randomly assigned into two groups, the intervention group (n = 26) and the control group (n = 21). The intervention group attended a 90-min oral health education program every 2 weeks for 3 months. The program consisted of oral hygiene instruction, facial and tongue muscle exercise, and salivary gland massage. The control group was provided only general information about oral health. The assessments of oral function, such as oral diadochokinesis of articulation, swallowing, taste threshold and salivary flow rate, were carried out before and after 3 months with or without intervention. RESULTS: A total of 38 participants (21 of intervention group and 17 of control group) completed the study protocol. In the intervention group, resting salivation significantly improved after the program. The second and third cumulated Repetitive Saliva Swallowing Test times significantly improved in the intervention group. The threshold for bitterness significantly lowered in the intervention group, whereas the sour threshold significantly heightened in the control group after 3 months (P < 0.05). CONCLUSIONS: The present study suggests that the educational program targeting oral function improvement is effective among the independent older population.

Factor analysis of the perception of clinical attire in the Dental Hospital, Tokyo Medical and Dental University.

This study analysed the perceptions of dental clinical attire among patients, dentists and dental students at the Dental Hospital, Tokyo Medical and Dental University using factor analysis to investigate what kinds of factors would underlie the perceptions and would guide evaluation of wearing items of dentist. The subjects comprised 146 patients, 97 dentists, and 81 students of the Dental Hospital. Using a five-point Likert scale, the subjects were asked to score their preferences for 35 items that might be worn by a dentist in the clinic. These scores were analysed using factor analysis and seven factors were extracted. The factors were classified into three categories; the first was a traditional factor representing the public self of dentists, next was casual factors representing the private self of individual dentists, and the other was practical factors. Using MANOVA and univariate ANOVA, differences in perceptions among the subjects were found for factors of casual items while that for traditional items not (P<0.05). Thus, clinical attire would be evaluated from the viewpoint of interplay between public self and private self of the clinician as well as practical aspects. The variation in perceptions would be influenced by wearers' gender and observers' age.

Trends in percentage of postgraduate dental trainees at dental clinics.

A facilities-group system designed to provide clinical training at dental clinics was developed after postgraduate clinical training became mandatory for dentists in Japan in 2006. As a result, there has been a steady increase in the number of dental clinics collaborating with dental school hospitals under this program. A larger number of dental clinics have also been designated as single-system facilities, program management facilities or collaborating facilities. However, it remains to be determined whether this increase in the number of dental clinics designated as clinical training facilities has led to an increase in the amount of training offered. Therefore, the purpose of this study was to investigate trends in the percentage of postgraduate dental trainees at dental clinics between fiscal years 2006 and 2010. The results showed no significant correlation among (1) the percentage of dental clinics designated as single-system collaborating facilities, (2) the percentage of training programs at dental clinics, and (3) the proportion of training program recruitment offers by dental clinics compared to the total number of recruits. These findings showed that increasing the number of collaborating dental clinics did not lead to an increase in the amount of clinical training at dental clinics. The findings also suggest that increasing the number of single-system or program management dental clinics is important in promoting clinical training at dental clinics.

Does mandatory postgraduate clinical training worsen geographic distribution of dentists in Japan?

Postgraduate clinical training for dentists has been mandatory in Japan since 2006. Hirata et al. reported that the geographic distribution of postgraduate dental trainees by prefecture in 2006 was worse than that of practicing dentists. This suggests that the postgraduate clinical training system could intensify the problem of distribution of dentists. In this study, therefore, we reviewed the geographic distribution of postgraduate dental trainees and practicing dentists between 2006 and 2010 in detail by city, ward, town and village by using the Lorenz curve and Gini coefficient. The results showed that while there was no significant worsening of geographic distribution of postgraduate dental trainees, the distribution of practicing dentists continued to deteriorate. A number of reasons may explain these findings: the clinical training system is based on a one-year employment contract, and dentists subsequently relocate as driven by the market; and geographic distribution among cities, towns and villages has worsened as a result of the merger of municipalities. The geographic distribution of practicing dentists is expected to deteriorate further if the number of dentists takes a downward turn in the future. Therefore, it is necessary to continuously review the distribution of postgraduate dental trainees.

Masseter muscle tension and chewing ability in older persons.

AIM: Mastication is an important function to maintain, not only for oral health, but also for quality of life. An easy-to-use method to evaluate the chewing ability of elderly people in any environment is necessary. Few studies have discussed the effectiveness of the masseter muscle by palpation. The purpose of this study was to clarify the availability of masseter muscle tension assessment methods by investigating its relationship with oral health status, and comparing it with other methods of assessing chewing ability. METHODS: This cross-sectional study was carried out with 547 community-dwelling elderly subjects (246 men and 301 women; mean age 73.8 ± 6.2 years) who participated in a comprehensive annual geriatric health examination in 2010 at Kusatsu, Gunma, Japan. Chewing ability was evaluated by masseter muscle tension palpation, differences of masseter muscle thickness, occlusal force, self-reported chewing ability, and the number of remaining and functional teeth. Masseter muscle thickness was measured by ultrasonography. RESULTS: Masseter muscle thickness and occlusal force showed significant differences between males and females. The strength of masseter muscle tension palpation was significantly associated with men's occlusal force, masseter muscle thickness, the number of remaining and functional teeth, and self-reported chewing ability (P < 0.05). Female participants showed a significant association with occlusal force, masseter muscle thickness, the number of remaining teeth, and self-reported chewing ability and results of palpation (P < 0.05). CONCLUSION: These results showed that the palpation of masseter muscle tension is a reliable and easy-to-use method to evaluate the chewing ability of elderly people.

The possibility of digital imaging in the diagnosis of occlusal caries.

The aim of this study was to assess the possibility of digital image analysis of pit-and-fissure discoloration in order to diagnose caries. Digital images showing pit-and-fissure discoloration in 100 teeth of 19 patients were analyzed to obtain the fractal dimension (FD) and the proportion of the area of pit-and-fissure discoloration to the area of occlusal surface (PA). DIAGNOdent values were measured (DD), and dentists' diagnoses were also obtained. The sensitivity and specificity of FD, PA, DD, and the combination of FD and PA compared to the dentists' diagnoses were calculated. The sensitivities of FD, PA, DD, and the combination of FD and PA were 0.89, 0.47, 0.69, and 0.86, respectively, and the specificities were 0.84, 0.95, 0.91, and 0.86, respectively. Although further research is needed for the practical use, it is possible to use the analysis of digital images of pit-and-fissure molar discoloration as a diagnostic tool.

Geographic distribution of postgraduate dental trainees in Japan.

Postgraduate clinical training for dentists in Japan became mandatory in April 2006. Mandatory postgraduate clinical training for physicians has been criticized as having accelerated the imbalance in distribution of physicians. This suggests the danger that the same phenomenon might occur in distribution of dentists. It is also necessary to investigate the geographic distribution of dental trainees and practicing dentists in Japan. In this study, the number of dental trainees enrolled in each clinical training program and number that had actually received clinical training at each facility were compared by prefecture. The results suggest that disparities in the number of dental trainees among prefectures are being compensated for by movement across prefectural borders under the clinical training facilities-group system. Postgraduate dental trainees, however, showed a significantly greater imbalance in geographic distribution than practicing dentists. Continuation of the postgraduate clinical training for dentists under the existing system may accelerate this imbalance in distribution of dentists. To prevent this, practical measures should be taken in accordance with the coming review of the system, based on research regarding changes in geographic distribution of dental trainees.

Subjective and objective assessments of short-term adverse effects induced by oral appliance therapy in obstructive sleep apnea: a preliminary study.

UNLABELLED: Abnormal occlusal sensation induced by wearing oral appliance (OA) was assessed in this study. MATERIALS AND METHODS: Twelve non-apneic healthy subjects with normal dental occlusion were used in this study. The 12 subjects slept wearing OAs at night. Occlusal sensation, biting force, occlusal contact area and muscle fatigue were evaluated every 15 minutes during 4 hours after removals of worn OAs when they waked up on the following morning. Same procedures were repeated on the same subjects after the sleep without OAs on the other day. RESULT: The differences of occlusal sensation was statistically significant up to 75 minutes after removal of OAs (p < 0.05). The difference of biting force was statistically significant immediately after removal of OAs (p < 0.05). There were statistically significant correlations (p < 0.05) between occlusal sensation and biting force in 9 of 12 subjects. Two of 12 subjects showed significant correlations (p < 0.05) between occlusal sensation and muscle fatigue. Only one of 12 subjects showed significant correlation (p < 0.05) between biting force and muscle fatigue. CONCLUSION: Abnormal occlusal sensation is probably elicited by non-physiological displacement of TMJs, nonphysiological extension of the chewing muscles and/or continuous compression toward the periodontal membranes by using OAs for hours at night.

Overweight patients with severe sleep apnea experience deeper oxygen desaturation at apneic events.

We investigated differences in the depth of hypoxia produced by apneic events of the same duration (30 seconds) amongst patients with different degrees of OSAS according to their AIs (apnea indices). The relationship between apnea duration (seconds) and fall in oxygen saturation (%) was evaluated by means of a linear regression analysis. The fall induced by a 30-second apnea event was designated as the "oxygen desaturation value 30" (ODV30). We analyzed the polysomnographic recordings of 122 OSAS patients who showed significant correlations (p<0.01) between apnea duration and subsequent fall in oxygen saturation and calculated their respective ODV30. We evaluated the influence of AI and BMI on ODV30 by multi-comparison and found out that standardized partial regression coefficients of BMI and AI were 0.578 and 0.148, respectively (multi-regression analysis, SPSS). BMI was proved to be more influential on ODV30 than AI was. On the other hand, the ODV30 of mild, moderate and severe OSAS patients was 8.84 +/- 2.62% (Mean +/- S.D.), 8.25 +/- 2.45% and 10.59 +/- 3.32%, respectively. Our study shows that fall in oxygen saturation is particularly extensive in severe OSAS patients and that fall in oxygen saturation is deepened as obesity increases. We think ODV30 is a useful variable for evaluating OSAS.

Tensile strength of dentin after bleaching treatment.

The mechanical properties of dentin are changed after bleaching, although the effects of the bleaching conditions on the tensile strength of dentin have not been determined. In the current study, a tensile test of bovine dentin was conducted after bleaching and the effects of the bleaching conditions were investigated, including the number of bleaching times, the location where the bleaching agent was applied, and the kind of illumination. The weight of organic content in dentin before and after application of the agent was also measured. The results showed that the tensile strengths did not change after three times office bleaching procedure, and the location where the bleaching agent was applied, the kind of bleaching agent and the kind of illumination did not have influence on the tensile strength. On the other hand, organic component in dentin significantly decreased after application of the agent (p<0.05). Since the bleaching agent would potentially affect tensile strength with deterioration of collagen matrix, the frequency of bleaching treatment should be minimized in clinical use.

An evaluation of self-reported oral health and health-related quality of life.

The purpose of this study was to investigate the general and oral health status of patients at a dental hospital in Tokyo and examine the correlations between general health and oral health items. One hundred and seventy-four (174) new patients at the Dental Hospital of Tokyo Medical and Dental University participated in this study. The Visual Analog Scale (VAS) was employed to investigate dental demands and symptoms, as well as satisfaction with oral and general health conditions, while SF-36 served an indicator for health-related quality of life (HRQOL). The results were statistically analyzed at a significance level of p = 0.05. The results of VAS were further examined using factor analysis. Several VAS items showed significant correlations with SF-36 subscales (p<0.05). The factor analysis of VAS items suggested a structure involving three factors: self-cognition of oral status, related function and pain, and dental fear and discomfort. The dental fear and discomfort factor showed no significant correlations with SF-36 subscales (p>0.05). Emotional elements and esthetic demands on dental status, as well as physical symptoms, influence HRQOL. Dental discomfort proved to be independent of general health status and was considered a dental-specific item that needs to be measured separately from general health status.

[Educative effect of feedback after medical interview in objective structured clinical examination].

OBJECTIVE: Objective Structured Clinical Examination (OSCE) is widely used to assess the core competency of dental residents. However, the educative effect of feedback in OSCE has not been fully examined. Therefore, we investigated the educative effect of formative feedback in a medical interview station. METHODS: The subjects were 51 residents in the clinical training course of our dental hospital. After completing the medical interview station, residents were individually given formative feedback by evaluators and standardized patients. Two months later, residents were asked to fill in a questionnaire about the contents of feedback and self-rating mental strain level during OSCE. Videotaped performance and feedback were reviewed by investigators to check the answers to the questionnaire. RESULTS: Evaluators provided an average of 3.1 feedback items, and standardized patients provided an average of 1.6 feedback items for each resident. However, each resident remembered an average of 1.3 feedback items from evaluators and 0.9 from standardized patients. The lower the score of residents in the medical interview station, the more feedback items were given to residents. A significant negative correlation was found between the score of evaluators and self-rating mental strain level (Spearman rho = -0.326, p = 0.019). CONCLUSION: For effective feedback, evaluators or standardized patients should focus on 2 to 3 items of essential points in OSCE. Repetition of feedback using videotaped performance may be useful to improve communication skills for medical interview.

Patient's perception of location, form and size in case of cavity preparation.

The aim of the present study was to clarify the difference between the imagination of patients and the reality in regard to the location, the form and the size of the cavity in case of cavity preparation for dental restoration. Firstly, we manufactured the dummy dentition for simulated cavity preparation and the operator intra-orally prepared a cavity on the dummy dentition in subject to confirm its validity. Then, 5 operators intra-orally prepared prescribed cavities at the both sides of maxillary first molars on the dummy dentition in every one of 5 subjects with masking. We compared the location, the form and the area of these prepared cavities with those imagined by subjects, respectively. In 58% of cases, the subjects could accurately recognize the location of prepared teeth. And 34% of cases also determined the Class of cavity form. The imagined area was larger than the actual area and the difference was statistically significant (p < 0.001). These results suggested that the perception of the patients regarding the location and the form of the prepared cavity was inaccurate during cavity preparation and patients tended to overestimate amounts of removed tooth substance.

Effects of chloramines and sodium hypochlorite on carious dentin.

In chemo-mechanical caries removal procedures, chloramines are typically used for chemical softening of carious dentin. However, the specific effect of chloramines to be compared to sodium hypochlorite has not been sufficiently clarified. In present study, the effect of chloramines used in the Carisolv-system on carious dentin mechanical properties and morphology were investigated, using Vickers hardness test and scanning electron microscopy (SEM). Sections of permanent teeth with dentin caries were treated with chloramines, prepared by mixing amino acids (glutamic acid, lysine, and leucine) with sodium hypochlorite or with sodium hypochlorite alone or with purified water. There was a tendency that the application of the sodium hypochlorite solution softened the sound dentin and/or inner layer of carious dentin more than the application of the chloramines solution did. In SEM observations, the application of chloramines resulted in opening dentinal tubules in the outer layer of carious dentin: Occluded dentinal tubules were seen after sodium hypochlorite application. There is a possibility that the amino acids in the Carisolv-system decrease the aggressive effect of sodium hypochlorite on sound dentin and/or inner layer of carious dentin and also would enhance the disrupting effect on degenerated collagen in carious dentin outer layer.

Evaluation of an articulated measuring apparatus for use in the oral cavity.

The aim of this study was to evaluate the trial Teaching Robot for the development of a contact-type measuring apparatus for using directly in the oral cavity. A standard model was used to mimic the dentition by placing an arrangement of three bearing balls. The diameters of the balls were measured. A practical dentition model was used. The coordinates were measured on the top of the buccal cusp of the right and left first premolars and the distal contact points of the right and left first molars and the mesial contact point of the right incisor. The arch width and length were calculated. The diameters of the bearing balls and the widths and lengths of the dental arches were not significantly different from the results of the XYZAX G-800D. Therefore, we suggest that the trial Teaching Robot has superior efficiency for measurements in oral cavity.