Background: Self-rated oral health is a valid and useful summary indicator of overall oral health status and quality of life. However, few studies on perception of oral health have been conducted among Japanese young adults. This study investigated whether oral health behavior, subjective oral symptoms, or clinical oral status were associated with self-rated oral health in Japanese young adults. Methods: This cross-sectional survey included 2,087 students (1,183 males, 904 females), aged 18 and 19 years, at Okayama University, Japan. A self-administered questionnaire was distributed and an oral examination was performed. Results: In a structural equation modeling analysis, the score of decayed, missing and filled teeth (DMFT) significantly affected self-rated oral health (p <0.05) and the effect size was highest. Malocclusion, subjective symptoms of temporomandibular disorders (TMD) and stomatitis, and poor oral health behavior significantly induced self-rated poor oral health with small effect sizes (p <0.05). Clinical periodontal conditions and Oral Hygiene Index-simplified were not related to self-rated oral health. Conclusion: Self-rated oral health was influenced by subjective symptoms of TMD and stomatitis, oral health behavior, the score of DMFT, and malocclusion. The evaluation of these parameters may be a useful approach in routine dental examination to improve self-rated oral health in university students.

Objective Many cross‐sectional studies have reported a relationship between overweight/obesity and eating quickly, but there have been few longitudinal studies to address this relationship in younger populations. The purpose of this prospective longitudinal study was to investigate whether eating quickly was related to being overweight in Japanese university students. Methods Of 1,396 students who underwent a general examination and completed questionnaires at the start of university and before graduation, 1,314 students (676 male and 638 female) of normal body composition [body mass index (BMI) < 25 kg m⁻²] at baseline were included in the analysis. The questionnaires included speed of eating and other lifestyle factors. After a 3‐year follow‐up, the students whose BMIs were ≥ 25 kg m⁻² were defined as overweight. Results In this study, 38 participants (2.9%) became overweight. In the logistic regression analysis, the risk of being overweight was increased in males [adjusted odds ratio (OR): 2.77; 95% confidence interval (CI): 1.33‐5.79; P < 0.01] and in those who ate quickly at baseline (OR: 4.40; 95% CI: 2.22‐8.75; P < 0.001). Conclusions Eating quickly may predict risk of being overweight in Japanese university students.

Most cross-sectional studies have found a significant positive relationship between periodontal disease and prehypertension/hypertension. However, these studies had limitations and there are few prospective cohort studies in young adults. The purpose of this prospective cohort study was to investigate whether periodontal disease was related to prehypertension/hypertension in Japanese university students. Students ( n = 2,588), who underwent health examinations before entering university and before graduation, were included in the analysis. The association between periodontal disease such as the percentage of bleeding on probing (BOP) and community periodontal index (CPI) scores, and change in blood pressure status was determined. At the reexamination, the numbers of participants with prehypertension (systolic blood pressure 120–139mm Hg or diastolic blood pressure 80–89mm Hg) and hypertension (≥140/90mm Hg) were 882 (34.1%) and 109 (4.2%), respectively. In a logistic regression model, the risk of hypertension was significantly associated with male (odds ratio (OR): 6.31; 95% confidence interval (CI): 2.63–15.13; P < 0.001), no habitual physical activity at baseline (OR: 2.90; 95% CI: 1.56–5.38; P < 0.01) and periodontal disease defined as the presence of both probing pocket depth (PPD) ≥ 4mm and BOP ≥ 30% at baseline (OR: 2.74; 95% CI: 1.19–6.29; P = 0.02) in participants with prehypertension at baseline. On the other hand, the risk of prehypertension was not associated with presence of periodontal disease (OR: 0.93; 95% CI: 0.51–1.70; P = 0.82). In the short-term prospective cohort study, a significant association between presence of periodontal disease and hypertension was observed in Japanese university students.