title: Putative factors associated with molar incisor hypomineralisation: an epidemiological study.
abstract: OBJECTIVE
  The aim of the study was to examine the aetiological factors involved in the development of molar incisor hypomineralisation (MIH).
  
  
  METHODS
  The study population comprised 4,049 children (2,029 girls, 2020 boys) aged 7-12 years. Children were examined for MIH in the school environment. Putative aetiological factors were evaluated using a questionnaire sent to children's families. The questionnaire included questions on prenatal, perinatal, and postnatal systemic conditions. Multivariate analysis was performed using multiple logistic regression, and Pearson's Chi-square test was used to evaluate nominal or ordinal variables with Fisher's exact test used in cases of small sample sizes. A level of p < 0.05 was considered statistically significant.
  
  
  RESULTS
  MIH was observed in 7.7 % of the study population. A total of 3,827 completed questionnaires were returned, yielding a response rate of 95.3 %. MIH was found to be associated with prematurity (7 %), gastrointestinal problems (3.9 %), pneumonia (6.3 %), frequent fever (26.1 %), measles (14.7 %), and chickenpox (29.3 %) before age 4 years.
  
  
  METHODS
  Prevalence did not vary significantly between girls and boys (p > 0.05). Prematurity, gastrointestinal problems, pneumonia, frequent high fever, measles, and chickenpox before age 4 years were found to be significantly related with MIH (p < 0.05).
  
  
  CONCLUSIONS
  The aetiology of MIH is not clear yet, and the results of this study support the results of previous studies regarding the putative causal effect of several factors.
authors.affiliation: Department of Paediatric Dentistry, Faculty of Dentistry, Ankara University, Ankara, Turkey, hayriyesonmez@hotmail.com.
authors.forename: H
authors.initials: H
authors.lastname: Sönmez
authors.forename: G
authors.initials: G
authors.lastname: Yıldırım
authors.forename: T
authors.initials: T
authors.lastname: Bezgin
mesh_terms: D003744:Dental Enamel Hypoplasia / Q000453:epidemiology; D016021:Epidemiologic Studies; D005334:Fever / Q000453:epidemiology; D006801:Humans; D007180:Incisor; D008963:Molar; D015995:Prevalence