Exploring the association between overweight and dental caries among US children.

PURPOSE The purpose of this study was to examine the relationship between age-specific body mass index (BMI-for-age) and dental caries among US children. METHODS Body measures data and oral health data came from the 1999-2002 National Health and Nutrition Examination Survey. Outcome measures for primary and permanent dentitions were: (1) dental caries prevalence; and (2) severity (geometric mean dft and DMFT). Covariates included: (1) age; (2) gender; (3) race/ethnicity; and (4) poverty status. Analysis was limited to children 2 to 17 years old. RESULTS Approximately 36% of overweight children 2 to 6 years old and 39% of overweight children 6 to 17 years old had dental caries. Geometric mean dental caries scores for overweight children were dft=3.3 and DMFT=2.5 for primary and permanent dentitions, respectively. Controlling for covariates, there was no significant association between BMI-for-age and dental caries prevalence in either dentition. In addition, among children with a positive history of dental caries, BMI-for-age was significantly associated with dental caries severity in the permanent dentition - overweight children had a lower geometric mean DMFT than did normal weight children. CONCLUSIONS Although it was hypothesized that age-specific body mass index would be associated with increased dental caries prevalence and severity, these associations were not found. Rather, overweight was found to be associated with lower geometric mean DMFT. Future studies should address which factors specific to overweight in children might be protective against dental caries in the permanent dentition. Given the importance of overweight as a public health problem, however, clinicians are encouraged to continue providing health education and dietary counseling to their overweight child patients.