Despite sufficient knowledge of good oral hygiene habits, dental students still suffer from oral health problems owing to dietary habits, obesity, and a sedentary lifestyle. This cross-sectional study was conducted to evaluate an association of BMI (body mass index), diet, physical activity, and oral hygiene practices with DMFT (decayed, missing, and filled teeth) of male dental students and interns at King Faisal University, Saudi Arabia, from August to September 2020. One hundred and eighty-five male participants completed the study questionnaire. The questionnaire consisted of sociodemographic information and nineteen close-ended questions about current diet, physical activity, and oral hygiene practices. Students' height (cm) and weight (kg) were measured to calculate BMI. The principal investigator performed the oral clinical examinations for the DMFT status in the dental clinic. The chi-square test was used for the dichotomous variables and a t-test was used for the continuous variables. Linear and multinomial logistic regression were performed to detect the significant predictors of the DMFT score. The mean age of participants was 22.29 ± 2.13 years, and the BMI was 24.94 ± 3.36 (Kg/m2). Parents' higher education and income levels were significantly (p < 0.001) associated with a higher BMI. Most dietary variables, especially sugar products, and low physical activity, were significantly (<0.047) associated with higher BMI. All oral hygiene practices, except miswak and mouthwash, were significantly (<0.003) associated with higher BMI. Decayed and missing teeth were significantly (<0.001) higher in the overweight and obese. A simple linear regression analysis demonstrated association between BMI and decayed teeth, with an R = 0.35 (<0.001); BMI and missing teeth had an R = 0.12 (p = 0.867); BMI and filled teeth had an R = 0.15 (p = 0.033), and BMI with DMFT had an R = 0.33 ((<0.001). This study demonstrated a strong significant association of the decayed and missing teeth with higher BMI levels. In addition, BMI was significantly associated with diet and physical activity, despite acceptable oral hygiene practices.
Keywords: BMI; DMFT; dental students; dietary habits; oral hygiene practices; physical activity.