Pre- and perinatal exposures associated with molar incisor hypomineralization: Birth cohort, Brazil

Objective: To analyze prenatal and perinatal stressors associated with molar incisor hypomineralization (MIH) in adolescents.Methods: Prospective cohort study collected prenatal (socioeconomic status, maternal age, number of prenatal visits, smoking, obesity during pregnancy, abortion history, gestational hypertension) and perinatal stressors (type of delivery, gestational age, birth weight, intensive care unit-ICU at birth). The outcome was MIH at 18-19 years follow-up (n = 590). MIH was defined according to the Ghanim criteria - Model I. We performed a sensitivity analysis, including opacities demarcated in index tooth, incisive or molars, Model II. Through structural equation modeling, we analyzed direct and mediating pathways between multiple stressors with outcomes.Results: MIH was observed in 15.25% (n = 90), and opacities demarcated in any index tooth were observed in 22.8% of adolescents (n = 135). In Model I, no stressor explained MIH significantly, although we watched high standardized coefficients (SC) for low birth weight (SC = 0.223, p = 0.147), lower gestational age (SC = 0.351; p = 0.254), and ICU admission (SC = 0.447, p = 0.254). In Model II, advanced maternal age (SC = 0.148; p < 0.05) and not undergoing prenatal care (SC = 0.384, p < 0.03) explained opacities demarcated in incisors or molars.Conclusion: Advanced maternal age and not undergoing prenatal care were associated with MIH lesion-like in incisors or molars.