The aim of this cross-sectional study was to evaluate the association between the influence of occupational stress and coping style on periodontitis among Japanese workers. The study sample included 738 workers (age range: 19–65 years) at a manufacturing company in Kagawa Prefecture, Japan. To analyze occupational stress and coping style, all participants answered a self-report questionnaire composed of items on their work environment and oral health behavior. Oral examinations were performed by calibrated dentists. Among all workers, 492 (66.7%) workers were diagnosed with periodontitis, and 50 (6.8%) were diagnosed with a high stress-low coping condition. Significant differences (p < 0.05) were observed between the periodontitis and non-periodontitis groups in terms of age, gender, body mass index, smoking status, daily alcohol drinking, monthly overtime work, worker type, and stress-coping style. Logistic regression analysis showed that a high stress–low coping condition was associated with an increased risk of periodontitis (odds ratio: 2.79, 95% confidence interval: 1.05–7.43, p = 0.039). These findings suggest that a high stress-low coping condition is associated with periodontitis among the 19–65 years of age group of Japanese workers.

Oral health behaviors, risk aversion, and the health belief model are associated with health behaviors. However, there have been few studies that investigated the association between these factors and the willingness to undergo regular dental check-ups. The purpose of this cross-sectional study was to investigate the associations between the willingness of Japanese university students to undergo regular dental check-ups and oral health behaviors, the health belief model, and absolute risk aversion. An analysis was conducted with the cooperation of questionnaire respondents (n = 748) who underwent dental check-ups at Okayama University. The students answered questionnaires on oral health behaviors, the health belief model, absolute risk aversion, and willingness to undergo regular dental check-ups. The logistic regression analysis showed significant positive associations (p < 0.05) between oral health behaviors (use of the inter-dental brush and the dental floss) and the health belief model with the willingness to undergo regular dental check-ups. However, there was no significant association with absolute risk aversion (p > 0.05). These results suggest that willingness to undergo regular dental check-ups was associated with oral health behaviors and the health belief model, but not with absolute risk aversion.

Self-rated oral health (SROH) is a valid, comprehensive indicator of oral health status. The purpose of this cross-sectional study was to analyze how oral health behaviors and clinical oral status were associated with SROH and how they had changed over the course of nine years in Japanese university students. Data were obtained from 17,996 students who underwent oral examinations and completed self-questionnaires from 2011 to 2019. Oral status was assessed using the decayed and filled teeth scores, bleeding on probing (BOP), probing pocket depth, the Oral Hygiene Index-Simplified (OHI-S), oral health behaviors, and related factors. SROH improved from 2011 to 2019. The logistic regression model showed that university students who were female and had a high daily frequency of tooth brushing, no BOP, no decayed teeth, no filled teeth, and a low OHI-S score and were significantly more likely to report very good, good, or fair SROH. An interaction effect was observed between survey year and regular dental check-ups (year × regular dental check-ups). The improvement trend in SROH might be associated with changes in oral health behaviors and oral health status.

Oral disease can cause economic loss due to impaired work performance. Therefore, improvement of oral health status and prevention of oral disease is essential among workers. The purpose of this study was to investigate whether oral health-related behavioral modification intervention influences work performance or improves oral health behavior and oral health status among Japanese workers. We quasi-randomly separated participants into the intervention group or the control group at baseline. The intervention group received intensive oral health instruction at baseline and a self-assessment every three months. Both groups received oral examinations and answered the self-questionnaire at baseline and at one-year follow-up. At follow-up, the prevalence of subjects who use fluoride toothpastes and interdental brushes/dental floss were significantly higher in the intervention group than in the control group. Three variables (tooth brushing in workplace, using fluoride toothpaste, and experience of receiving tooth brushing instruction in a dental clinic) showed significant improvement only in the intervention group. On the other hand, work performance and oral status did not significantly change in either group. Our intensive oral health-related behavioral modification intervention improved oral health behavior, but neither work performance nor oral status, among Japanese workers.

The long-term effects of secondhand smoke (SHS) on dental caries among Japanese young adults remain unclear. The purpose of this cross-sectional study was to evaluate whether household exposure to SHS is associated with dental caries in permanent dentition among Japanese young adults. The study sample included 1905 first-year university students (age range: 18–19 years) who answered a questionnaire and participated in oral examinations. The degree of household exposure to SHS was categorized into four levels according to the SHS duration: no experience (−), past, current SHS < 10 years, and current SHS ≥ 10 years. Dental caries are expressed as the total number of decayed, missing, and filled teeth (DMFT) score. The relationships between SHS and dental caries were determined by logistic regression analysis. DMFT scores (median (25th percentile, 75th percentile)) were significantly higher in the current SHS ≥ 10 years (median: 1.0 (0.0, 3.0)) than in the SHS—(median: 0.0 (0.0, 2.0)); p = 0.001). DMFT ≥ 1 was significantly associated with SHS ≥ 10 years (adjusted odds ratio: 1.50, 95% confidence interval: 1.20–1.87, p < 0.001). Long-term exposure to SHS (≥10 years) was associated with dental caries in permanent dentition among Japanese young adults.

Although some studies showed that lifestyle was associated with oral health behavior, few studies investigated the association between household type and oral health behavior. The aim of this prospective cohort study was to investigate the association between household type, oral health behavior, and periodontal status among Japanese university students. Data were obtained from 377 students who received oral examinations and self-questionnaires in 2016 and 2019. We assessed periodontal status using the percentage of bleeding on probing (%BOP), probing pocket depth, oral hygiene status, oral health behaviors, and related factors. We used structural equation modeling to determine the association between household type, oral health behaviors, gingivitis, and periodontitis. At follow-up, 252 students did not live with their families. The mean ± standard deviation of %BOP was 35.5 ± 24.7 at baseline and 32.1 ± 25.3 at follow-up. In the final model, students living with their families were significantly more likely to receive regular dental checkup than those living alone. Regular checkup affected the decrease in calculus. The decrease in calculus affected the decrease in %BOP over 3 years. Living with family was directly associated with regular dental checkups and indirectly contributed to gingival status among Japanese university students.