Dental caries incidence and associated factors in young adults

To assess the caries incidence from late adolescence to early adulthood and to identify the factors associated with caries incidence.

This is a secondary analysis of longitudinal caries data of young adults aged 17-23 from the Iowa Fluoride Study cohort. The inclusion criteria required completion of dental exams at both ages 17 and 23 and having cumulative exposure (AUC) variables data for at least 8 out of the 11 time periods between ages 17 and 23. Mean imputation was used to handle the missing explanatory variable data. Multiple linear regressions were conducted using a generalized linear model to assess the effects of sociodemographic and behavioral/dietary variables on the age 17-23 adjusted cavitated caries (D₂₊ MFS) increment (AdjCI_17-23 ). Multicollinearity was assessed using the variance inflation factor (VIF) and the final model was selected based on the Akaike Information Criterion (AIC) using backward selection and the net effects calculated.

The mean AdjCI_17-23 was 2.08 (SD = 4.02). The net effects (main effect plus interactions) of higher composite socioeconomic status, higher combined daily fluoride intake, higher frequency of milk intake, lower amount of sugar-sweetened beverages intake, and lower age 17 dental caries counts were associated with lower mean AdjCI_17-23 .

The incidence of caries from age 17 to 23 in this study was low. This study suggests and reinforces the need to continue to advocate for caries preventive strategies such as fluoride use, encouraging milk intake, and reducing sugar-sweetened beverage intakes.