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Published on: March 29, 2018
Enamel fluorosis prevalence after a 7-year interruption in water fluoridation in Jaú, São Paulo, Brazil
Marília A R Buzalaf1, Beatriz S de Almeida, Kelly P K Olympio
1Bauru Dental School, University of São Paulo, Brazil. mbuzalaf@fob.usp.br
Objectives:
This paper analyzes the impact of a 7-year interruption in water fluoridation on the prevalence of enamel fluorosis in Jaú, state of São Paulo, Brazil.
Methods:
Fluorosis prevalence (TF index) was evaluated in permanent maxillary central incisors of children (9-14 years old) that were 36 (n=81; cohort -36), 27 (n=81; cohort -27), and 18 months old (+/-1 month; n=89; cohort -18) in October 1991, when the breakstarted, and 18months old(+/-1 month;n=70; cohort 18) after that date. Children brushed their teeth prior to examination, which was conducted under natural light by three calibrated examiners (agreement 87.8-93.8%, kappa 0.72-0.85).
Results:
The fluorosis prevalence (TF> or =1) was 7.41 percent, 3.70 percent, 7.87 percent, and 18.57 percent, respectively, for cohorts -36, -27, -18, and 18. The difference between cohort 18 and the other groups was statistically significant (Kruskall-Wallis test, P=.05).
Conclusions:
These results suggest that the fluoridated water is not an important risk factor for enamel fluorosis, since the prevalence of enamel fluorosis was low in the cohorts -36, -27, and -18 when fluoridated water was used.
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