Data sourcesPubMed, Web of Knowledge, Scopus and Scielo.Study selectionTwo reviewers identified studies supervised by a third. Observational studies which investigated the association between developmental defects of enamel and dental caries in the primary dentition, which were assessed by clinical examination and published in English, Spanish or Portuguese.Data extraction and synthesisQuality of research was assessed using the critical appraisal checklist from the Joanna Briggs Institute. Meta-analysis was conducted using crude and adjusted association measures (relative risk and odds ratio) with 95% confidence intervals. Combined results were presented as pooled odds ratio, and where necessary were estimated using fixed and random effect models. If heterogeneity was encountered in results, a random effect model was used. Bias was assessed using a funnel plot and the Egger test.ResultsEighteen studies were included in the systematic review and sixteen in meta-analysis; two out of the 16 were cohort studies, the rest being cross-sectional. Twelve of the studies included were conducted in low-income countries. The Egger test showed a degree of bias in some of the studies included. The authors found children with diffuse opacities or hypoplasia had higher odds of having dental caries (OR 1.42, 95% CI; 1.15-1.76; OR 4.29% CI 2.24-8.15), however the presence of demarcated opacities did not show higher odds of caries (OR 2.62, 95% CI 0.85-8.12).ConclusionsThe findings demonstrated an association between developmental defects of enamel and dental caries in the primary dentition. A preventive approach to dental caries and attention to children with enamel defects appears as a useful health promotion and public health strategy. At the individual level, clinicians should be aware that children with enamel defects could require more frequent visits to the dental office in order to reduce the risk of dental caries.