The aim of this study was to determine the prevalence of hypoplasia, demarcated opacity and dental fluorosis among schoolchildren with deciduous and permanent dentition. The association between enamel defects and dental caries was also verified. The sample consisted of 624 schoolchildren aged 5 and 309 aged 12. The dmft and DMFT indexes were used to assess dental caries prevalence, DDE to assess enamel defects, and Dean to assess fluorosis. Chi-squared test was used to test significance (p < 0.05) and odds ratio to analyze prevalence of dental caries and enamel defects. A positive association between dental caries and enamel defects (hypoplasia, demarcated opacity and dental fluorosis) was observed for schoolchildren aged 5. However, only hypoplasia and demarcated opacity were associated with caries experience in permanent dentition. The results of this study indicated that children had increased odds of dental caries when enamel defect was present, both in deciduous and permanent dentition; further studies are needed to give evidence to this association.