Objective: To investigate the association between molar-incisor hypomineralization (MIH) and enamel hypoplasia.
Study design: The sample consisted of 311 orthodontic files of patients aged between 12 and 18 years, divided into two groups: patients with MIH (109) and without MIH (202). MIH and enamel hypoplasia were diagnosed via panoramic radiographs and intraoral photographs, followed by clinical examination of the MIH-affected patients as per the modified EAPD scoring criteria. Chi-square test and t test were used to assess intergroup comparisons regarding sex, age and race. Fisher's Exact test was used to compare the groups regarding the presence of enamel hypoplasia and the Adjusted Odds Ratios (OR) were calculated.
Results: There was an association between MIH and enamel hypoplasia. The prevalence of enamel hypoplasia (5.5%) was significantly higher in patients with MIH compared to the control group (0.49%). MIH lesions increase 12.45-fold the risk of having enamel hypoplasia.
Conclusion: Patients with MIH have a higher prevalence of enamel hypoplasia and these defects seem to share the same etiological factor.
Keywords: Enamel hypoplasia; Molar incisor hypomineralization; Paediatric dentistry; comparison.