RESUMEN
OBJECTIVE: The aim of this study was to assess the prevalence and severity of dental erosion among 12-year-old schoolchildren in Joaçaba, southern Brazil, and to compare prevalence between boys and girls, and between public and private school students. METHODS: A cross-sectional study was carried out involving all of the municipality's 499, 12-year-old schoolchildren. The dental erosion index proposed by O'Sullivan was used for the four maxillary incisors. Data analysis included descriptive statistics, location, distribution, and extension of affected area and severity of dental erosion. RESULTS: The prevalence of dental erosion was 13.0% (95% confidence interval = 9.0-17.0). There was no statistically significant difference in prevalence between boys and girls, but prevalence was higher in private schools (21.1%) than in public schools (9.7%) (P < 0.001). Labial surfaces were less often affected than palatal surfaces. Enamel loss was the most prevalent type of dental erosion (4.86 of 100 incisors). Sixty-three per cent of affected teeth showed more than a half of their surface affected. CONCLUSION: The prevalence of dental erosion in 12-year-old schoolchildren living in a small city in southern Brazil appears to be lower than that seen in most of epidemiological studies carried out in different parts of the world. Further longitudinal studies should be conducted in Brazil in order to measure the incidence of dental erosion and its impact on children's quality of life.