Supplementary Material for: Predictors of Developmental Defects of Enamel in Primary Maxillary Central Incisors using Bayesian Model Selection

Introduction Localized non-inheritable developmental defects of tooth enamel (DDE) are classified as enamel hypoplasia (EH), opacity (OP) and post-eruptive breakdown (PEB) using the Enamel Defects Index. To better understand the etiology of DDE, we assessed the linkages amongst exposome variables for these defects during the specific time duration for enamel mineralization of the human primary maxillary central incisor enamel crowns. In general, these two teeth develop between 13-14 weeks in utero and 3-4 weeks’ postpartum of a full-term delivery, followed by tooth eruption at about 1 year of age. Methods We utilized existing datasets for mother-child dyads that encompassed 12 weeks’ gestation through birth and early infancy, and child DDE outcomes from digital images of the erupted primary maxillary central incisor teeth. We applied a Bayesian modeling paradigm to assess the important predictors of EH, OP, and PEB. Results The results of Gibbs variable selection showed a key set of predictors: mother’s prepregnancy body mass index (BMI); maternal serum concentrations of calcium and phosphorus at gestational week 28; child’s gestational age; and both mother’s and child’s functional vitamin D deficiency (FVDD). In this sample of healthy mothers and children, significant predictors for OP included the child having a gestational period > 36 weeks and FVDD at birth, and for PEB included a mother’s prepregnancy BMI < 21.5 and higher serum phosphorus concentration at week 28. Conclusion In conclusion, our methodology and results provide a roadmap for assessing timely biomarker measures of exposures during specific tooth development to better understand the etiology of DDE for future prevention