Prevalence, clinical characteristics, and treatment needs of Molar Incisor Hypomineralization (MIH) in Turkish children: a cross-sectional study

Molar Incisor Hypomineralization (MIH), with a reported global prevalence of 15.5%, is considered a significant dental public health problem due to its distinct clinical manifestations in affected teeth. This study aimed to determine the prevalence of MIH in a large sample of Turkish children attending a university pediatric dental clinic and to evaluate lesion characteristics, treatment needs, and patterns of hypersensitivity at both the patient and tooth levels. This study was designed as a clinic-based cross-sectional study. A total of 1,680 children aged 8–13 years presenting to a university pediatric dental clinic were initially examined; of these, 97 children in whom not all first permanent molars were clinically assessable were excluded. The final analytical sample therefore comprised 1,583 children. Clinical status, lesion extension, and the Treatment Need Index (TNI) were recorded for first permanent molars and incisors. Hypersensitivity was assessed clinically using the Schiff Cold Air Sensitivity Scale and dichotomized as present (scores 1–3) or absent (score 0). Prevalence and confidence intervals (CIs) were calculated using binomial methods. Group comparisons were performed using chi-square tests. Patient-level analyses were conducted using count regression models to describe the distribution of MIH-affected teeth per child, while tooth-level associations with hypersensitivity were analyzed using binary logistic regression models with adjustment for within-child clustering. MIH was diagnosed in 295 children, corresponding to a prevalence of 18.6% (95% CI: 16.6–20.5). Molars were more frequently affected (79.7%) than incisors (22.9%; p < 0.001). Hypersensitivity was predominantly concentrated in molars, with the highest proportions observed in mandibular molars (up to 24%), whereas incisors showed minimal involvement. Logistic regression showed that post-eruptive enamel breakdown and atypical caries were most strongly associated with hypersensitivity (OR = 4.94 and OR = 6.44, respectively; p < 0.001). MIH affected nearly one in five to six children in this clinic-based pediatric population. First permanent molars were the most severely affected teeth, whereas incisors were predominantly characterized by demarcated opacities. Hypersensitivity was primarily associated with destructive lesion types, particularly post-eruptive enamel breakdown and atypical caries.