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Trends in dental caries prevalence in 12-year-old schoolchildren between 1976 and 2001 in Bauru, Brazil
R da Silva Bastos1, K P K Olympio, V T Bijella
1Department of Paedodontics, Orthodontics and Collective Health, University of São Paulo, Bauru, SP, Brazil.
Objective:
To evaluate the trends in dental caries prevalence in 12-year-old schoolchildren between 1976 and 2001 in Bauru, Brazil. Study design. An epidemiological survey was performed by trained, calibrated examiners by the same research group in 1976, 1984, 1990, 1995 and 2001, using the decayed, missing and filled teeth (DMFT) index.
Methods:
Urban elementary schools were chosen because they provide a fair representation of the city's population in terms of socio-economic status. The study included 261, 321, 253, 377 and 211 subjects from the same regions in 1976, 1984, 1990, 1995 and 2001, respectively. The prevalence of caries and the DMFT index were used.
Results:
A remarkable decrease was seen in the DMFT index at age 12 (84.53%) between 1976 and 2001. The DMFT indices at age 12 were 9.89, 7.01, 3.97, 4.13 and 1.53 in 1976, 1984, 1990, 1995 and 2001, respectively. The percentage of schoolchildren presenting with sound permanent teeth (DMFT = 0) increased from 0.40 to 45.50% between 1976 and 2001. Over the same period, the percentage of schoolchildren with six or more decayed teeth decreased from 86.99% to 5.21%.
Conclusions:
The phenomenon of dental caries polarization is already perceptible in Bauru, Brazil. The increase in the number of schoolchildren with sound permanent teeth (DMFT = 0) suggests that the dental health policy in Bauru has had a positive effect in children's dental health, and should therefore be considered for other cities.
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