Kampo medicine, which developed uniquely in Japan on the basis of Chinese medicine ─ one of the systems of traditional Eastern medicine ─ has inherited the concept of mibyou. In contrast, in the field of preventive dentistry within Western medicine, the concept of the “three levels and five stages of prevention” based on the natural history of disease was proposed in 1958 by Leavell and Clark. This framework was subsequently applied mainly to dental caries, periodontal disease, and tooth loss by Dunning in 1962. The classification of preventive levels from primary to tertiary prevention, together with the five stages of preventive measures, has since become well established in preventive medicine in Japan. Accordingly, when Kampo prescriptions are considered from the perspectives of the natural history of disease and levels of health proposed by Leavell and Clark, as well as the stages of prevention for dental diseases proposed by Dunning and the concept of treating mibyou, Kampo medicine is considered to be particularly suitable for specific protection in primary prevention and for early detection and early treatment in the initial stages of disease in secondary prevention.

  To revise criteria for dental caries disease type O2 at 1.6-year dental health examinations (1.6-year checkups), this study aimed to investigate the relationship between the incidence of dental caries and risk factors in 3-year-old children. In total, 3324 children, who had undergone both 1.6- and 3-year dental health examinations in A City, had no dental caries at the 1.6-year checkup, and there were no missing data. Using the presence or absence of dental caries at the 3-year checkup as the dependent variable, we performed binary logistic regression analysis. Explanatory variables included sex, family size, daytime childcare, breastfeeding, bottle use, parental smoking, parental tooth-brushing assistance, frequency of eating/drinking between meals, fluoride application, thumb sucking, and number of primary teeth. The factor most significantly associated with dental caries development in terms of the odds ratio was care by grandparents, followed in order by breastfeeding, frequency of eating/drinking between meals, family size, paternal smoking, maternal smoking, parental tooth brushing, and number of primary teeth. A cutoff value was determined using the receiver operating characteristic curve created with the above eight items. When dividing cases into those with two or fewer items and those with three or more items, the sensitivity was 65.8% and specificity was 69.2%. The risk factors for dental caries incidence identified in this study may contribute to revising the criteria for dental caries disease type O2.

  Ensuring safe dental care requires effective infection control measures, particularly during procedures that generate droplets. Although suction devices reduce droplet exposure, the use of extraoral vacuum devices remains limited because of installation costs, noise, and spatial constraints. To provide visually intuitive infection control education, we developed a 20‑minute educational video incorporating droplet‑visualization footage obtained from simulated dental procedures. The video consisted of three parts: fundamentals of infection control, characteristics of droplets produced during dental treatments, and the effectiveness and limitations of intra- and extraoral vacuum devices. To evaluate changes in awareness and behavioral intentions, 260 dentists at a university hospital completed a questionnaire immediately after viewing the video. Logistic regression analysis showed that the intention to increase future use was highest for extraoral vacuum devices (76.3%), and odds ratios for all other PPE and suction devices were significantly lower than for the reference category (FWER‑adjusted p<0.05). To indirectly assess behavioral changes in clinical settings, noise levels in five dental clinics were measured before and after the training. The frequency of noise exceeding 65 dB, an indirect indicator of extraoral vacuum operation, showed a significant post‑training increase, although noise does not directly confirm device usage. These findings suggest that visually explicit educational materials, particularly those that make droplet behavior observable, can enhance dentists’ awareness of infection control and may encourage behavioral changes, such as the increased use of extraoral vacuum devices.

  In this study, we aimed to evaluate the accessibility of dental care services for the ≥75-year-old population across Japan using two indicators: a distance- and time-based accessibility index rate, relying on straight-line distances from dental clinics and automobile travel time accounting for road networks and topographical conditions (dAIR and tAIR-car), respectively. Moreover, we examined the associations of these indices with dental-care use rates and dental expenditure.

  We used 500-m mesh population data for individuals aged at least 75 years from the 2020 Population Census, along with medical institution data from the 2020 National Land Numerical Information. In this analysis, we included a total of 68,806 dental clinics nationwide. Using ArcGIS Pro, we calculated the size of older adult populations living outside service catchment areas, defined by 16-km dAIR and 15-min tAIR-car.

  The results indicated that, based on the nationwide average, 2.27% of the population aged ≥75 years resided outside a 15-min automobile catchment area. We observed higher tAIR-car values in prefectures such as Kochi, Iwate, Wakayama, and Akita, displaying high aging rates and challenging topographical conditions. Furthermore, the 15-min tAIR-car exhibited weak negative correlations with dental-care use rates and dental expenditures, suggesting that reduced geographic accessibility is associated with decreased dental-care service use.

  This study represents an accessibility evaluation based on realistic travel feasibility, which is difficult to ascertain using conventional distance-based measures. Thus, the findings will hopefully contribute to a better understanding of the current state of dental care access among older adults.

  This cross-sectional study aimed to determine the prevalence of oral frailty and associated factors among Japanese residents of Vietnam.

  A total of 125 participants were analyzed using a self-reported online questionnaire, which included questions about: sociodemographic factors, lifestyle, language skills, mental health, nutritional status, risk of severe periodontal diseases, social participation, and physical activities. The outcome variable, oral frailty, was assessed using the oral frailty checklist (OF-5). More than two “yes” responses to five questions were considered indicative of oral frailty.

  The prevalence of oral frailty in this population was 22.4%. Irregular sleep (p=0.003), English-speaking skills (p=0.049), risk of severe periodontal diseases (p<0.001), and psychological distress (p<0.001) showed significant correlations with oral frailty. Logistic analysis revealed that those with risks of severe periodontal diseases (OR, 5.26; 95%CI, 1.61–17.21; p=0.006) and psychological distress (OR, 5.04; 95%CI, 1.54–16.47; p=0.007) were more likely to develop oral frailty than those without them.

  The findings suggest that risks of severe periodontal diseases and psychological distress may serve as indicators of oral frailty in this population.

  An observational study was conducted to investigate symptoms of oral immune-related adverse events (irAEs) in nine patients receiving immune checkpoint inhibitors (ICI) alone or in combination with other drugs. The most common oral symptom after ICI administration was the lichenoid reaction, with the buccal mucosa as the most common site of onset. Severities of oral mucositis (OM), oral pain, and dry mouth were greater in patients receiving both ICI and other drugs compared with those receiving ICI alone. Numbers of days from the first to final ICI administration until the onset of OM were examined; however, no significant differences were observed between the two groups. The number of ICI administrations and doses before symptom onset also showed no significant differences between the two groups. Local steroids (ointments and gargles) were effective in treating oral mucositis, suggesting the potential benefit of topical steroid therapy.