Aim: This study aimed to determine the prevalence, pattern and severity of MIH in school children resident in a suburban population in Nigeria.
Methods: This was a cross-sectional study involving pupils aged 8-10 years resident in suburban Nigeria. Details of each pupil's socio-demographic variables were collected. Intra-oral examination was conducted to determine the presence of MIH, the affected tooth and the severity of the lesion. The association between the prevalence of MIH and socio-demographic variables of each child was determined. The predictors of MIH were also determined using a binomial regression analysis.
Result: Eighty-three of the 469 children examined (17.7 %) had MIH. There was no significant association between sex (p = 0.58), socio-economic status (p = 0.09), age (p = 0.26) and MIH. There was also no significant difference in the number of teeth affected by MIH in the maxilla and mandible, and on the right and left side of the face. The most commonly affected teeth were the left mandibular molars. The occlusal surfaces of the first molars were mostly affected by MIH and the severity of MIH on the teeth examined varied from mild (80.8 %), moderate (14.0 %) to severe (5.2 %).
Conclusion: The prevalence of MIH in this study population is consistent with previous reports. The non-association between sex and MIH prevalence, the varied severity of the lesion and association between MIH affectation of the first permanent molars and central incisors give more weight to the possible role of environmental factors in the aetiology of the lesion. The non-association between MIH and socio-economic status may serve as a distinctive feature of MIH and chronological enamel hypoplasia.