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Distribution and Clinical Characteristics of MIH in Schoolchildren From the Central Peruvian Jungle: A
Mayra Belen Barahona-Hernandez1, Roxana Patricia López-Ramos2, Julio César Sánchez-Sotomayor3
1Department of Paediatric Stomatology, Faculty of Dentistry, Universidad Nacional Mayor de San Marcos, Lima, Peru, unmsm.edu.pe.
Background:
Molar incisor hypomineralisation (MIH) is a developmental enamel defect that predominantly affects first permanent molars and frequently involves incisors. However, evidence on MIH prevalence and clinical presentation in jungle regions is limited.
Aim:
To determine the distribution and clinical patterns of MIH among schoolchildren in the Central Jungle region of Peru.
Materials And Methods:
This cross-sectional study included 1500 schoolchildren aged 6-12 years from two public schools in Peru's Central Jungle region, recruited through stratified random sampling. Two calibrated examiners diagnosed MIH using European Academy of Paediatric Dentistry (EAPD) criteria (inter-examiner κ = [0.87]; intra-examiner κ = [0.89]). Categorical variables were analysed using Pearson's chi-squared and Fisher's exact tests (α = 0.05, 95% CI).
Results:
MIH prevalence was 18.8% (95% CI: [17.0-20.0]). First permanent molars were predominantly affected (upper: 84.8%, 285/336; lower: 90.9%, 288/317) compared to incisors. Pattern I distribution occurred in 78.7% of cases, while patterns II/III (21.3%) showed significant male predominance (p = 0.008). Molars exhibited significantly greater severity (p = 0.001) with white-cream opacities (28.5%) and predominantly Type III lesions, presenting higher post-eruptive breakdown and atypical caries rates. Incisors displayed mainly mild Type I demarcated opacities. Upper lateral incisors demonstrated left-sided predominance (p = 0.016).
Conclusion:
MIH prevalence was 18.8% among schoolchildren in Peru's Central Jungle region. First permanent molars were predominantly affected (upper: 84.8%; lower: 90.9%) compared to incisors. Pattern I distribution occurred in 78.7% of cases, while patterns II/III (21.3%) showed significant male predominance. Molars exhibited greater clinical severity with white-cream opacities, Type III lesions, and higher rates of post-eruptive breakdown and atypical caries, whereas incisors presented mainly mild demarcated opacities.
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