title: Prevalence of malocclusion in primary dentition in a population-based sample of Brazilian preschool children.
abstract: OBJECTIVE
  The purpose of the present study was to assess the prevalence of malocclusion in the primary dentition in a randomised representative sample of Brazilian preschool children.
  
  
  METHODS
  A cross-sectional survey was carried out in Belo Horizonte, Brazil, involving 1069 male and female preschool children from 60 to 71 months of age, randomly selected from public and private preschools and daycare centers. A questionnaire addressing demographic data was sent to parents/guardians in order to characterise the sample. The oral examination of the children was performed by a single, previously calibrated dentist (kappa inter-examiner agreement value = 0.82). The criterion for the categorisation of malocclusion was at least one of the following conditions: posterior crossbite, overjet (> 2 mm), anterior crossbite, anterior open bite and deep overbite. Univariate analysis was performed using the SPSS software
  
  
  RESULTS
  The prevalence of malocclusion was 46.2%. Deep overbite was the most prevalent alteration (19.7% of the sample). Posterior crossbite was diagnosed in 13.1% of the children; 10.5% had accentuated overjet; 7.9% had anterior open bite; and 6.7% had anterior crossbite.
  
  
  CONCLUSIONS
  Malocclusion in primary dentition is becoming a significant problem. The prevalence in the present study was high, especially vertical and transversal malocclusions.
authors.affiliation: Department of Pediatric Dentistry and Orthodontics, School of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
authors.forename: A C
authors.initials: AC
authors.lastname: Carvalho
authors.forename: S M
authors.initials: SM
authors.lastname: Paiva
authors.forename: A C
authors.initials: AC
authors.lastname: Scarpelli
authors.forename: C M
authors.initials: CM
authors.lastname: Viegas
authors.forename: F M
authors.initials: FM
authors.lastname: Ferreira
authors.forename: I A
authors.initials: IA
authors.lastname: Pordeus
mesh_terms: D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D004522:Educational Status; D005260:Female; D006801:Humans; D007182:Income; D008297:Male; D008310:Malocclusion / Q000145:classification / Q000453:epidemiology*; D024343:Open Bite / Q000453:epidemiology; D010290:Parents / Q000193:education; D010865:Pilot Projects; D011159:Population Surveillance; D015995:Prevalence; D012923:Social Class; D014094:Tooth, Deciduous / Q000473:pathology*