title: Prevalence of sleep bruxism in a group of Brazilian schoolchildren.
abstract: OBJECTIVE
  This was to investigate the prevalence of sleep bruxism in Brazilian schoolchildren.
  
  
  METHODS
  A cross-sectional study was carried out examining 652 randomly selected children aged from 7 to 10 years of age from both public and private schools in Belo Horizonte, Brazil. Sleep bruxism among children was reported by parents by means of a pretested questionnaire based on the criteria of the American Academy of Sleep Disorders. The Social Vulnerability Index from Municipal database was used to determine social classification of families. A chi-square test was used with a significance level of 5%.
  
  
  RESULTS
  Sleep bruxism was present in 230 children, showing a prevalence of 35.3%. Among the 652 children, 340 (52.0%) were girls and 312 (48.0%) were boys, predominatly of 8-year-olds (84.2%). Sleep bruxism was present in 56.5% of the girls and 43.5% of the boys. The majority of the families were of a low social vulnerability (54.2%), whereas another 45.8% were of a high social vulnerability. More than half of the children without sleep bruxism (55.2%) were of low socio-economic background.
  
  
  CONCLUSIONS
  The high prevalence of 35.3% demonstrates the need for further research on this issue.
authors.affiliation: Dept. of Paediatric Dentistry and Orthodontics of Federal University of Minas Gerais, Av Antonio Carlos, 6627, Faculdade de Odontologia, Belo Horizonte, MG, Brasil, 31270-901. juniaserranegra@hotmail.com
authors.forename: J M
authors.initials: JM
authors.lastname: Serra-Negra
authors.forename: S M
authors.initials: SM
authors.lastname: Paiva
authors.forename: A P
authors.initials: AP
authors.lastname: Seabra
authors.forename: C
authors.initials: C
authors.lastname: Dorella
authors.forename: B F
authors.initials: BF
authors.lastname: Lemos
authors.forename: I A
authors.initials: IA
authors.lastname: Pordeus
mesh_terms: D001938:Brazil / Q000453:epidemiology; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D017533:Marital Status / Q000706:statistics & numerical data; D011159:Population Surveillance; D015995:Prevalence; D057566:Self Report; D020186:Sleep Bruxism / Q000453:epidemiology*; D012923:Social Class; D011795:Surveys and Questionnaires; D035862:Vulnerable Populations / Q000706:statistics & numerical data