Molar Incisor Hypomineralization and Periodontitis in Adolescents: A Population-Based Study

To investigate the association between molar incisor hypomineralization (MIH) and periodontitis in adolescents.

A population-based study was undertaken of Brazilian adolescents aged 18 and 19 years (n = 2515). MIH was assessed according to Ghanim's criteria. The outcomes were Periodontitis Indicators, a continuous latent variable estimated on the basis of the common variance shared by the indicators bleeding on probing (BoP), probing pocket depth (PPD ≥ 4 mm) and clinical attachment level (CAL ≥ 3 mm), as well as periodontitis cases defined according to CDC-AAP. Structural equation modelling was used, and the models were adjusted for lower socioeconomic status, sex, smoking, triglycerides/high-density lipoprotein (TG/HDL) (mg/dL) and visible plaque index. Two other approaches were used for sensitivity analysis: (i) logistic regression, considering the effect of MIH on periodontitis (CDC/AAP) at the individual level, and (ii) multilevel regression to evaluate the association of MIH with CAL and PPD, considering the tooth as the unit of analysis, adjusted for other tooth-level and individual-level variables.

The prevalence of MIH was 16.86% (n = 423). Individuals with MIH had higher values of the Periodontitis Indicators through a direct pathway (standardized coefficient [SC] = 0.193, p < 0.001) and indirectly mediated by biofilm (SC = 0.263, p < 0.001). MIH was also associated with periodontitis according to CDC-AAP (SC = 0.071, p < 0.001) and indirectly mediated by biofilm (SC = 0.344, p < 0.001). Consistently, lower socioeconomic status, sex, TG/HDL and biofilm were associated with both periodontal outcomes. Tooth-level sensitivity regression analysis confirmed the association observed in individual-level analyses.

Our findings suggest that adolescents with MIH are susceptible to periodontitis, and it is therefore important to monitor their periodontal health.