Prevalência de hipomineralização molar-incisivo e fatores associados em escolares de um município do sudeste brasileiro

Abstract

Although studies worldwide have investigated potential factors involved in the occurrence of molar incisor hypomineralization (MIH), the findings are varied and inconclusive. Thus, the aim of this study was to determine the prevalence and investigate the factors associated with the occurence of molar incisor hypomineralization in a group of schoolchildren aged eight and nine years. A cross-sectional study was conducted with a population-based sample. The random sample, stratified between public and private schools, consisted of 1181 children residents in Lavras, Minas Gerais, Brazil. Prior to the main study, a pilot study was carried out to test the methodology. Data were collected via clinical examination and self-administered questionnaires completed by mothers. Mothers completed a self-administered questionnaire with questions on prenatal, perinatal and postnatal aspects, and another questionnaire on socioeconomic and demographic aspects. MIH was diagnosed using the criteria of the European Academy of Pediatric Dentistry. During the clinical examination, the presence of caries in permanent and primary dentitions, according to the recommendations of the World Health Organization (WHO) and developmental defects of enamel (DDE) in the second primary molars using the Developmental Defects of enamel Index (DDE index) also were evaluated. Oral examinations were performed by a single examiner who had undergone a training exercise. Data analysis involved descriptive statistics, bivariate tests and Poisson regression with robust variance (p<0.05, IC95%). This study was approved by the Ethics Committee of the Federal University of Minas Gerais, Brazil (CAAE 10659812.0.0000.5149).The prevalence of MIH was 20.4%. MIH was more frequent among children with dental caries in permanent dentition (PR: 2,67; 95%CI: 1,98-3,61); those with DDE on the primary second molars (PR: 2,54; 95%CI: 1,87-3,45) and those who experienced asthma and/or bronchitis in the first 4 years of life (PR: 1,93; 95%CI: 1,45-2,56). In conclusion, the prevalence of MIH was high in the present sample. The occurrence of MIH was more frequent in children with caries experience in the permanent dentition, those with enamel defects on primary second molars and those who had asthma experience in the first four years of life, even after controlling for potential confounding factors.