Social determinants of health are associated with molar-incisor hypomineralization (MIH): Results from a cross-sectional study in Bavaria, Germany

This population-based study investigated the associations between Molar Incisor Hypomineralization (MIH), caries, and the social determinants of health represented by a family's socioeconomic status (SES), regional Gross Domestic Product (GDP), and regional population density in 8- to 10-year-olds from Bavaria, Germany. A total of 5418 children from 87 randomly selected schools were clinically examined. Parental questionnaires were distributed to collect information on the families' SES, and 1315 questionnaires (representing the subsample) were available. Regional GDP and population density data were retrieved from official databases. The data were analysed using marginalized zero-inflated negative binomial regression, and Incidence Rate Ratios (IRR) and adjusted Odds Ratios (aOR) were determined. In the subsample (aged 9.7 ± 0.6 years, 47 % female), the prevalence rates of MIH and caries in the primary (idmft > 0) and permanent dentitions (IDMFT > 0) were 20.0 %, 33.0 %, and 14.6 %, respectively. Regression analyses revealed that the SES (IRR: 1.14 (1.02 - 1.27)), GDP (IRR: 2.58 (1.34 - 5.00); aOR: 5.23 (3.74 - 7.32)), and population density (IRR: 1.27 (1.11 - 1.45); aOR: 1.30 (1.14 - 1.48)) were significantly associated with MIH. Significant trends were observed between the SES (IRR: 0.90 (0.85 - 0.96); aOR: 0.90 (0.82 - 0.98)), GDP (IRR: 1.52 (1.77 - 1.96); aOR: 2.82 (1.80 - 4.42)), and population density (aOR: 1.13 (1.03 - 1.25)) and caries. Similar trends were observed in the data from the total sample. The results revealed consistent positive associations between MIH and the social determinants of health. These findings challenge conventional assumptions about oral health disparities, as MIH was more prevalent in more prosperous, rather than disadvantaged populations.