Prevalence, Severity and Treatment Needs of Molar Incisor Hypomineralization Among a Cohort of Lebanese Children: A Cross-Sectional Study

Objectives: The aim of the study was to assess the prevalence, severity and treatment needs of molar incisor hypomineralization (MIH) among a cohort of children in Lebanon. Methods: A cross-sectional study was performed in Akkar district in northern Lebanon on 1237 school children between 10 and 12 years old (mean age 11.11 ± 0.80 years) who were recruited from eight private schools. Clinical evaluations were performed after teeth cleaning and drying using sterile gauze. Examiners assessed all teeth present in the oral cavity using the MIH index of the EAPD. If MIH was diagnosed, a further grading was made according to the MIH-TNI index. Results: In total, 212 children (17.14% [95% CI:15.0, 19.2]) were diagnosed with MIH. Of these, 200 children with completed documentation were included in the further statistical analysis. Out of the affected cases, mild lesions were the most common at 41% (n = 82). Although males exhibited higher cumulative numbers of affected teeth (52.5%, n = 267), with notably greater proportions in moderate (17.7%) and severe (16.7%) cases, the difference between genders was not statistically significant (p = 0.069). Treatment needs increased with severity, in which mild lesions primarily required preventive care (41.0%), while moderate lesions required restorative treatments (34.0%); in contrast, severe lesions (25.0%) often necessitated extensive interventions, such as crowns, pulp therapies or even extractions. Although descriptive patterns suggested an increase in more complex treatment needs in older age groups, the association was not statistically significant (p = 0.26). Conclusions: The prevalence of MIH observed in this cohort study aligns with internationally reported values. Early detection, preventive management, and timely restorative interventions are essential to minimize the long-term impact of MIH.