Molar-incisor hypomineralisation: a prevalence study amongst primary schoolchildren of Shiraz, Iran

Eur Arch Paediatr Dent. 2014 Apr;15(2):75-82. doi: 10.1007/s40368-013-0067-y. Epub 2013 Jul 17.


Aim: To investigate the prevalence of molar-incisor hypomineralisation (MIH) amongst primary schoolchildren of Shiraz, Iran, taking into account the possible influence of biographic and socio-demographic parameters.

Study design and methods: A randomised cluster sample of 9- to 11-year-old children (N = 810) had their first permanent molars and incisors (index teeth) evaluated using the European Academy of Paediatric Dentistry criteria for MIH. The examinations were conducted at schools by a calibrated examiner. Prevalence of MIH was assessed based on biographic and socio-demographic parameters including area of residency, school type, father's level of education, weight-for-age and height-for-age.

Results and statistics: Of the children examined, 164/810 (20.2%) had MIH and 53.7% of them presented with MIH lesions in all first molars. Mild defects represented by demarcated yellow brown opacities comprised 35.5% of the total MIH lesions. The prevalence of MIH was significantly greater in girls, children with healthy body weight and height, those whose fathers did not have a tertiary education and from families of low socio-economic status. Regression analyses indicated that none of the biographic and socio-demographic variables represented a significant risk factor in the occurrence of MIH except for body weight. Obesity was negatively correlated to MIH (OR = 0.45; 95% CI 0.25-0.82).

Conclusions: The prevalence of MIH in a group of Iranian children was 20.2%. Biographic and socio-demographic parameters appeared to have no significant correlation with MIH except body weight, which warrants further research.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Body Height
  • Body Weight
  • Child
  • Dental Enamel Hypoplasia / epidemiology*
  • Educational Status
  • Fathers / education
  • Female
  • Humans
  • Incisor / pathology
  • Iran / epidemiology
  • Male
  • Molar / pathology
  • Obesity / epidemiology
  • Prevalence
  • Residence Characteristics / statistics & numerical data
  • Schools / statistics & numerical data
  • Sex Factors
  • Social Class