Comparison of the prevalence of molar incisor hypomineralization among children with different health care coverage in the cities of Buenos Aires (Argentina) and Montevideo (Uruguay).

The aim of this study was to compare the prevalence of molar incisor hypomineralization (MIH) among children with different health care coverage in Buenos Aires and Montevideo. An observational, cross-sectional and descriptive study was designed, considering children born from 1993-2003 who were seen in the Chairs of Comprehensive Children's Dentistry (Universidad de Buenos Aires) and of Pediatric Dentistry (Universidad de la República) and at five private dental offices between April and December 2010. Two groups were defined: A (Buenos Aires; n=1,090) and B (Montevideo; n=626). The clinical diagnosis was carried out with calibrated examiners (Kappa: 0.94) using the Mathu-Muju and Wright criteria. The prevalence of MIH was found to be 16.1% in A and 12.3% in B (p=0.03), with statistically significant differences between the public and private care sectors in both groups (A p=0.0008; B p=0.0004) and a positive correlation between MIH and year of birth (A p=0.001; B p=0.005). The results show that MIH is an emerging pathology and that MIH prevalence is related to year of birth and access to health care.