[Trends in dental caries rates in schoolchildren 12 and 13 years old in Florianópolis, Santa Catarina, Brazil, 1971-2002, in Florianópolis, Santa Catarina, Brazil].

The goal of this study was to identify dental caries prevalence and severity among all 12 and 13-year-old schoolchildren enrolled in a public school in 2002 and to establish comparisons with the results of studies conducted previously in the same school in 1971 and 1997. A cross-sectional study involving 181 children was performed. Clinical data were collected by one examiner under World Health Organization (WHO) criteria. The examiner had been through calibration training. The project was approved by the Research Ethics Committee of the Federal University in Santa Catarina. The response rate was 93.8%. Intra-examiner agreement, on a tooth-by-tooth basis, was high (Kappa> or =0.73). The prevalence rates for dental caries were 98%, 93.7% or 80.0%, and 57.4% in 1971, 1997, and 2002, respectively. The mean DMF-T index was 9.2 in 1971, 6.2 or 3.0 in 1997, and 1.4 in 2002, taking both ages as a whole. The first value from 1997 was recorded under the Klein & Palmer diagnostic criterion and the second according to the WHO criterion. Between 1971 and 2002 there was a real reduction in caries prevalence and severity among the schoolchildren, even though different diagnostic criteria were used.