Body Mass Index and caries: analysis from the FACCT study

Objectives To determine the prevalence of dentinal caries and obesity in 8-year-old schoolchildren and to explore the association between Body Mass Index (BMI) and dentinal caries. Methods In 2016-17 a sample of 8-year-olds in Cork/Kerry and Dublin were clinically examined for caries in the primary dentition. Caries was identified when the lesion had extended into dentine. Standardised methods were used to record height and weight. BMI categories of normal weight, overweight and obese were determined using the International Obesity Task Force Classification. Parents/caregivers provided information on demographics, home water supply, oral health behaviours, frequency of snacking on foods high in sugars and physical activity via questionnaire. Associations between BMI and caries were investigated using logistic regression models adjusted for exposure to fluorides, age, gender, parent’s education, county, healthcare cover, snacking frequency, physical activity, fluoridation status, first dentist visit. Significance level was p<0.05. Results A total of 2291 8-year-old children were examined for this study, mean age 8.3(0.37) years-old. The prevalence of dentinal caries in the primary dentition was 59%. The proportion of children identified with a normal body weight was 74%, overweight 9% and obese 16%. The prevalence of caries in children with normal weight was 58% compared to 64% and 63% for the children in the overweight and the obese categories, respectively (p=0.08). In fully adjusted regression models, children who were overweight had 1.37 times the odds of having dental caries compared to children with normal weight (95% CI:0.95-1.97; p=0.09) while children with obesity had 1.11 times the odds (95% CI:0.85-1.44; p=0.43). Conclusions These preliminary analyses indicate that BMI may be associated with the presence of dentinal caries=. After adjusting for variables including snacking frequencies and physical activity, BMI remained associated with dental caries. Further research should be conducted to explore this relationship.