title: Environmental factors, sleep duration, and sleep bruxism in Brazilian schoolchildren: a case-control study.
abstract: OBJECTIVE
  The purpose of our study was to evaluate the association between environmental factors, sleep duration, and sleep bruxism (SB) in schoolchildren.
  
  
  METHODS
  A case-control study was performed. Individuals participating in the study were randomly chosen from public and private schools in Belo Horizonte, Brazil. A total of 120 children with bruxism and 240 without bruxism (mean age, 8 years) participated in our study. A questionnaire for parents was used to collect data based on criteria taken from the American Academy of Sleep Medicine. Conditional binary logistic regression statistical tests and χ2 tests were used for analysis.
  
  
  RESULTS
  The final logistical model found that children with a median sleep time < or = 8 h per night (odds ratio [OR], 2.561 [95% confidence interval {CI}, 1.480-4.433]), who did not enjoy a good night's sleep (OR, 3.253 [95% CI, 1.600-6.615]), who slept with noise in the room (OR, 2.699 [95% CI, 1.645-4.429]), and who had the light on (OR, 2.370 [95% CI, 1.446-3.884]), were more likely to have SB.
  
  
  CONCLUSIONS
  Children who sleep for less than 8h a night are more likely to have SB. Light and noise in the room were two predisposing factors for the occurrence of SB.
authors.affiliation: Department of Pediatric Dentistry and Orthodontics of Universidade Federal de Minas Gerais, Av. Antonio Carlos 6627, Pampulha, Belo Horizonte 31901270, Minas Gerais, Brazil. Electronic address: juniaserranegra@hotmail.com.
authors.forename: Junia Maria
authors.initials: JM
authors.lastname: Serra-Negra
authors.affiliation: Department of Pediatric Dentistry and Orthodontics of Universidade Federal de Minas Gerais, Av. Antonio Carlos 6627, Pampulha, Belo Horizonte 31901270, Minas Gerais, Brazil.
authors.forename: Saul Martins
authors.initials: SM
authors.lastname: Paiva
authors.affiliation: Department of Pediatric Dentistry and Orthodontics of Universidade Federal de Minas Gerais, Av. Antonio Carlos 6627, Pampulha, Belo Horizonte 31901270, Minas Gerais, Brazil.
authors.forename: Lívia Bonfim
authors.initials: LB
authors.lastname: Fulgêncio
authors.affiliation: Department of Pediatric Dentistry and Orthodontics of Universidade Federal de Minas Gerais, Av. Antonio Carlos 6627, Pampulha, Belo Horizonte 31901270, Minas Gerais, Brazil.
authors.forename: Bertha Angelica
authors.initials: BA
authors.lastname: Chavez
authors.affiliation: Department of Pediatric Dentistry and Orthodontics of Universidade Federal de Minas Gerais, Av. Antonio Carlos 6627, Pampulha, Belo Horizonte 31901270, Minas Gerais, Brazil.
authors.forename: Carolina Freitas
authors.initials: CF
authors.lastname: Lage
authors.affiliation: Department of Pediatric Dentistry and Orthodontics of Universidade Federal de Minas Gerais, Av. Antonio Carlos 6627, Pampulha, Belo Horizonte 31901270, Minas Gerais, Brazil.
authors.forename: Isabela Almeida
authors.initials: IA
authors.lastname: Pordeus
mesh_terms: D001938:Brazil / Q000453:epidemiology; D016022:Case-Control Studies; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D009622:Noise / Q000009:adverse effects; D010290:Parents; D012890:Sleep / Q000502:physiology; D020186:Sleep Bruxism / Q000453:epidemiology / Q000209:etiology*; D012892:Sleep Deprivation / Q000150:complications; D011795:Surveys and Questionnaires; D013997:Time Factors
keywords: Bruxism; Children; Dentistry; Epidemiology; Parafunction; Parasomnia; Sleep duration