title: Enamel fluorosis prevalence after a 7-year interruption in water fluoridation in Jaú, São Paulo, Brazil.
abstract: OBJECTIVE
  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.
authors.affiliation: Bauru Dental School, University of São Paulo, Brazil. mbuzalaf@fob.usp.br
authors.forename: Marília A R
authors.initials: MA
authors.lastname: Buzalaf
authors.forename: Beatriz S
authors.initials: BS
authors.lastname: de Almeida
authors.forename: Kelly P K
authors.initials: KP
authors.lastname: Olympio
authors.forename: Vanessa E
authors.initials: VE
authors.lastname: da S Cardoso
authors.forename: Sílvia H
authors.initials: SH
authors.lastname: de C S Peres
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005457:Fluoridation / Q000706:statistics & numerical data*; D009050:Fluorosis, Dental / Q000453:epidemiology*; D006801:Humans; D007180:Incisor / Q000473:pathology; D007223:Infant; D008437:Maxilla; D015995:Prevalence; D012307:Risk Factors; D018709:Statistics, Nonparametric; D013997:Time Factors