Prevalence of Molar Incisor Hypomineralization Among Iranian Children: Systematic Review and Meta-Analysis

Document Type : Review Article(s)

Authors

1 Student Research Committee, Qazvin University of Medical Sciences, Qazvin, Iran

2 Department of Pediatric Dentistry, Dental School, Qazvin University of Medical Sciences, Qazvin, Iran

3 Non-Communicable Diseases Research Center, Research Institute for Prevention of Non-Communicable Diseases, Qazvin University of Medical Sciences, Qazvin, Iran

Abstract

Background: Molar incisor hypomineralization (MIH) represents a qualitative developmental defect of the enamel that most commonly manifests in the permanent first molars, with possible extension to the permanent incisors. Several studies have investigated MIH across different regions of Iran. The aim of this systematic review and meta-analysis was to determine the overall prevalence of MIH in Iran.
Methods: Scientific databases such as PubMed, Scopus, and ISI Web of Science, as well as Iranian databases including Magiran (Magiran.com) and Idml.research.ac.ir, were searched until April 2025. Studies with a cross-sectional design on the prevalence of MIH were included. To calculate the pooled prevalence, random effects models were used. Assessment of heterogeneity was performed using meta-regression and sensitivity analyses.
Results: Fourteen eligible studies were included in the quantitative analysis. The pooled prevalence of MIH in Iran was calculated at 21.6% (95% CI, 15.5 to 27.7%). The prevalence was 23.5% (95% CI, 12.8 to 34.2%) in girls and 22.4% (95% CI, 15.9 to 24.9%) in boys. According to meta-regression, MIH prevalence increased with increasing age, but this was not statistically significant (P = 0.518).
Conclusion: We observed high heterogeneity in the reported prevalence of MIH among the primary studies. MIH is a widespread dental condition in Iran, with a pooled prevalence of 21.6%, which appears higher than the global prevalence. Therefore, it is necessary to improve dental healthcare providers’ awareness regarding this condition and to consider MIH during routine dental examinations.

Keywords

Main Subjects

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Journal of Oral Health and Oral Epidemiology
Volume 15
Pages 1-9

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History

  • Receive Date: 05 May 2025
  • Revise Date: 31 August 2025
  • Accept Date: 06 December 2025

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