Molar-Incisor Hypomineralization in Schoolchildren of São Luis, BrazilMaranhão: Prevalence and Associated Factors

Abstract

Objective: To determine the prevalence of molar-incisor hypomineralization (MIH) in the permanent dentition and assess the factors associated with these change in schoolchildren of São Luís, Brazil. Material and Methods: Overall, 1179 students aged 7-14 years of both sexes were included, all with permanent first molars and incisors erupted in the oral cavity. Oral clinical examination to assess the prevalence of HMI was held at school, under natural light. In the second stage, to assess factors associated with HMI, a case-control study was conducted, in which cases were children diagnosed with HMI (n = 14) and as controls, the schoolchild's brother (family control, n = 10 ) and another schoolchild in the same age group born in the same locality (community control, n = 14). A semistructured questionnaire was completed by mothers to identify possible factors associated with HMI, such as maternal education, family income, data from pregnancy and child's medical history in the first three years of life. Logistic regression analysis was used to estimate odds ratios (Odds Ratio -OR) and their confidence intervals at 95% (CI 95%) to assess crude and adjusted associations for confounders. Results: A prevalence of 2.5% of HMI was estimated. No association was found for the etiologic factors surveyed. Conclusion: The prevalence of HMI was lower than that reported in other cities in Brazil, but similar to data from other countries. At the difficulty and complexity in establishing the etiologic factors of HMI, cohort studies are required to clarify this change.

A systematic review and meta‐analysis of systemic exposure associated with molar incisor hypomineralization

“…The characteristics of the 29 eligible studies are presented in Table . Fourteen were cross‐sectional studies, ten were case‐control studies and four were cohort studies . The number of patients included in the studies varied from 45 to 4049 children with a mean age of 9 years.…”

“…One study that was excluded presented a high risk of bias . Sixteen studies presented moderate risk of bias and 12 studies showed low risk of bias (Table ).…”

“…Considering alcohol consumption during pregnancy and MIH, only two studies could be included in the meta‐analysis, and they presented contrasting findings, which resulted in a greater heterogeneity. The MIH diagnosis may be one of the factors behind the different findings: while Pitiphat et al used the criteria from EAPD 2003, Rodrigues et al used the modified DDE index, which was not specifically developed for MIH diagnosis.…”

“…Recent literature on MIH aetiology is based on retrospective study designs which evaluated the exposures associated with this enamel defect . Some studies report its aetiology based on the use of antibiotics, the occurrence of fever during pregnancy or fever in the first years of the child's life, the use of cigarette during pregnancy, maternal alcohol use, stress and respiratory infections such as asthma and pneumonia also predict MIH.…”

“…Systematic reviews investigated the systemic exposures associated with MIH, including exposures during the prenatal, perinatal and postnatal periods. Children with respiratory problems, complications during delivery, low birth weight, lack of oxygen at birth, metabolic, calcium and phosphate disturbances, asthma, respiratory tract infections, high fever and antibiotic consumption were associated with increased presence of MIH . However, none systematic review was meta‐analysed to check associations of the predictor factor and the occurrence of MIH.…”