title: Prevalence of dental wear among 12-year-old Brazilian adolescents using a modification of the tooth wear index.
abstract: OBJECTIVE
  This study investigated the prevalence of dental wear in 12-year-old adolescents using a modification of the tooth wear index (TWI). The modifications were proposed in order to fit with the World Health Organization standard, thus allowing application of the index in broad epidemiological surveys.
  
  
  METHODS
  An epidemiological cross-sectional survey was performed by trained, calibrated examiners, using a modified version of the TWI.
  
  
  METHODS
  Urban elementary schools were chosen because they provide a fair representation of the city's population in terms of socio-economic status. The sample included 295 adolescents, selected randomly and systematically. Dental wear was assessed by calibrated examiners (kappa>0.85), using a modified version of the TWI. This modified version includes a code for teeth restored due to wear, and another code for teeth that cannot be assessed. In addition, it does not differentiate the depth of dentine involvement. Proportions and confidence intervals were used to describe the prevalence of dental wear. Mann-Whitney test was used to detect differences in the degree of dental wear between males and females. The level of statistical significance was set at 5%.
  
  
  RESULTS
  In total, 24,780 dental surfaces were evaluated. Among these surfaces, 73.10% did not present dental wear, 24.10% had incipient lesions, 2.46% had moderate lesions and 0.34% had been restored. No severe lesions were detected. Tooth wear was mainly seen on the occlusal/incisal surfaces (26.55%), involving enamel or enamel-dentine, but not the secondary dentine or pulp. The prevalence of dental wear was 26.90%. Considering the different teeth, wear was present in 53.22% of incisors, 50.51% of canines, 10.17% of premolars and 10.85% of molars. The prevalence of the different degrees of dental wear was similar in males and females (P>0.05).
  
  
  CONCLUSIONS
  The modified TWI seems to be an effective tool for use in broad epidemiological surveys, due to easier calibration and high reproducibility rates.
authors.affiliation: Department of Paedodontics, Orthodontics and Public Health of Dentistry, Bauru School of Dentistry, University of São Paulo, Bauru, SP, Brazil. shcperes@usp.br
authors.forename: S H
authors.initials: SH
authors.lastname: de Carvalho Sales-Peres
authors.forename: S
authors.initials: S
authors.lastname: Goya
authors.forename: J J
authors.initials: JJ
authors.lastname: de Araújo
authors.forename: A
authors.initials: A
authors.lastname: Sales-Peres
authors.forename: J R P
authors.initials: JR
authors.lastname: Lauris
authors.forename: M A R
authors.initials: MA
authors.lastname: Buzalaf
mesh_terms: D001938:Brazil / Q000453:epidemiology; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence; D014072:Tooth Abrasion / Q000175:diagnosis / Q000453:epidemiology*