Prevalence of developmental defects of enamel in Brazil: a systematic review and meta-analysis

To estimate the pooled prevalence of developmental defects of enamel (DDE), specifically molar-incisor hypomineralisation (MIH), hypomineralised second primary molars (HSPM), enamel hypoplasia, and dental fluorosis, in the Brazilian population.

A comprehensive literature search was performed through PubMed, Web of Science, Scopus, Embase, SciELO and LILACS databases following PRISMA guidelines. The grey literature search was conducted on Google Scholar. Cross-sectional studies reporting prevalence data of DDE in Brazil were included. Risk of bias was assessed using the Joanna Briggs Institute Checklist for Prevalence Studies. A random-effects meta-analysis was performed to determine the pooled prevalence. Subgroup analyses were performed to investigate potential sources of heterogeneity.

Fifty-eight studies were included in the quantitative synthesis, comprising 42,337 participants across all five Brazilian geographic regions. The pooled prevalence was 15.6% (95% CI: 13.2%-18.4%; I² = 95.6%) for MIH, 12.5% (95% CI: 8.5%-18%; I² = 96.2%) for HSPM, 4.5% (95% CI: 2.3%-8.7%; I² = 95.7%) for enamel hypoplasia and 18.3% (95% CI: 9.9%-31.3%; I² = 98.2%) for dental fluorosis. Subgroup analyses showed geographic location as a significant source of variation (p < 0.001). Enamel hypoplasia was more prevalent in primary dentition (10.4%) than permanent dentition (2.9%) (p = 0.002), whilst dental fluorosis was higher in permanent (22%; 95% CI: 9.5%-43.2%) than primary dentition (11.2%; 95% CI: 6.4%-18.8%).

DDEs are highly prevalent in Brazil, with geographic region and dentition type contributing to variability.