title: Effect of the widespread use of fluorides on the occurrence of hidden caries in children.
abstract: BACKGROUND
  It has been suggested that the widespread use of fluorides could interfere in the prevalence of clinically undetected occlusal dentine caries.
  
  
  OBJECTIVE
  The objective of this study was to determine the role of public water fluoridation and fluoride dentifrice on the prevalence of hidden caries in 8-10-year-old children.
  
  
  METHODS
  Clinical and radiographic data on schoolchildren collected in an epidemiologic study in Porto Alegre, Brazil, at two moments, 1975 (n = 228) and 1996 (n = 213), were analysed. Only the first permanent molars were studied. Only children of the 1996 examinations had benefited from fluoridated water soon after birth and had regular access to fluoride dentifrices. The criterion applied for hidden caries, when data from 1975 to 1996 were compared, was clinical sound surfaces that presented a radiolucent zone in the dentine.
  
  
  RESULTS
  The prevalence of clinically sound surfaces and percentage of hidden caries was 0.51 and 26.4% in 1975 and 2.67 and 12.9% in 1996, respectively. The prevalence of hidden caries differed statistically between the two periods (P < 0.05).
  
  
  CONCLUSIONS
  The results do indicate that the widespread use of fluoride via public water supply and dentifrices decreases the prevalence of hidden caries.
authors.affiliation: Department of Preventive and Social Dentistry, Faculty of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, Brazil. lhashizume@yahoo.com
authors.forename: Lina N
authors.initials: LN
authors.lastname: Hashizume
authors.forename: Telma C
authors.initials: TC
authors.lastname: Mathias
authors.forename: Débora M
authors.initials: DM
authors.lastname: Cibils
authors.forename: Marisa
authors.initials: M
authors.lastname: Maltz
mesh_terms: D001938:Brazil / Q000453:epidemiology; D002327:Cariostatic Agents / Q000627:therapeutic use*; D002648:Child; D015331:Cohort Studies; D004245:DMF Index; D003731:Dental Caries / Q000453:epidemiology*; D003743:Dental Enamel / Q000187:drug effects; D003802:Dentifrices / Q000627:therapeutic use; D003804:Dentin / Q000187:drug effects; D004522:Educational Status; D016021:Epidemiologic Studies; D005260:Female; D005457:Fluoridation / Q000706:statistics & numerical data; D005459:Fluorides / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008963:Molar / Q000187:drug effects; D010290:Parents / Q000193:education; D015995:Prevalence; D016300:Radiography, Bitewing
chemical_list: D002327:Cariostatic Agents; D003802:Dentifrices; D005459:Fluorides