Prevalence, defect characteristics and distribution of other phenotypes in 3- to 6-year-old children affected with Hypomineralised Second Primary Molars

Purpose To assess the prevalence, severity and defect characteristics of hypomineralised second primary molars in schoolgoing children along with distribution of other phenotypes. Methods A total of 3013, 3- to 6-year-old children were examined for the presence of hypomineralised second primary molars (HSPMs) using an adapted version of EAPD Criteria (2003). The molars were evaluated for the presence, location and colour of demarcated opacities along with associated post-eruptive breakdown (PEB) and atypical restorations. A thorough examination of the entire dentition was followed for evaluation of teeth other than primary second molars for the presence of similar hypomineralised defects. Data were analysed using Chi Square, Fisher exact's and Mann-Whitney U tests at alpha = 0.05. Results A total of 3013 out of 3200 children were included having a mean age of 4.25 +/- 0.5 years and deft of 2.1 +/- 0.5. Using the adapted version of EAPD 2003 criteria for MIH, the children were evaluated for the presence of hypomineralised second primary molars, the prevalence of which was found to be 7.9%. Hypomineralisation defects were more commonly observed in the maxillary arch (53.4% vs. 42.8%, p = 0.04) with creamish white opacities involving the buccal and lingual surfaces being the most common defects (43.6%). The mean number of HSPMs per child was 1.9. Other phenotypes included demarcated opacities majorly on primary canines (6.6%) followed by primary first molars (4.6%). Conclusions Hypomineralised primary second molars are a fairly common condition affecting approximately 7.9% of the population thus warranting early recognition and management.