Potential Association of Molar-Incisor Hypomineralization (MIH) with Dental Agenesis and Infraoccluded Deciduous Molars: Is MIH Related to Dental Anomaly Pattern (DAP)? An Observational Cross-Sectional Study

Abstract

Background: Dental Anomaly Pattern (DAP) is a collection of morphologic, numeric, and eruptive anomalies of teeth that are often observed together, suggesting a potential genetic relationship. Our objective was to assess the potential associations of Molar-Incisor Hypomineralization (MIH), a common developmental defect of enamel mineralization with a controversial etiology, with two specific components of DAP: (1) agenesis (AG) and (2) infraoccluded deciduous molars (IODM). Establishing such an association between MIH and one or both anomalies would provide evidence supporting a genetic link between MIH and DAP. Methods: We examined pretreatment intraoral standardized photographies and panoramic radiographs from 574 children aged 8–14 years, 287 having MIH and 287 without MIH, comparing the frequencies of AG and IODM in both groups. The subject samples were sourced from the databases of the orthodontic department at a university hospital. Results: The frequencies of AG in the MIH and non-MIH groups were 7% and 8%, respectively (p = 0.751). The corresponding frequencies of IODM were 27% and 19.2%, respectively (p = 0.082). That is, children with MIH did not exhibit an increased frequency of AG or IODM compared to those without MIH. Conclusions: These findings do not support the inclusion of MIH in DAP. Nevertheless, further analysis of possible associations is necessary to definitively validate or invalidate this hypothesis.