Enamel Fluorosis Prevalence after a 7‐year Interruption in Water Fluoridation in Jaú, São Paulo, Brazil

Abstract

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. 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). 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). 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.