title: Prevalence and distribution of demarcated opacities and their sequelae in permanent 1st molars and incisors in 7 to 13-year-old Brazilian children.
abstract: OBJECTIVE
  To determine the prevalence of demarcated opacities in permanent 1st molars and incisors in 7 to 13-year-old Brazilian children.
  
  
  METHODS
  The study population comprised 292 children from a middle social class public school in Rio de Janeiro, Brazil. Children with all 1st permanent molars erupted were eligible for participation. Clinical examination was performed by two calibrated examiners who recorded demarcated opacities, post-eruptive breakdown, atypical restorations, and extractions due to demarcated opacities. Forty-three children had at least one molar that could not be examined, which left 249 children for the data analysis.
  
  
  RESULTS
  One hundred children (40.2%) had one or more 1st molars with demarcated opacities with a mean number of 1.98 (SD 1.09) affected molars. The number of affected incisors increased with increasing number of affected molars. Twenty-two (18.6%) of 118 children with unaffected 1st molars had affected incisors. Demarcated opacities were the most frequent defect, and 1st molars and upper central incisors were the most frequently affected teeth. Among children with demarcated opacities in 1st molars, 20 (20%) had post-eruptive breakdown.
  
  
  CONCLUSIONS
  A high prevalence of demarcated opacities, possibly resulting in disintegration of the tooth crown, has been found in Brazilian children.
authors.affiliation: Department of Preventive and Community Dentistry, School of Dentistry, State University of Rio de Janeiro, Rio de Janeiro, Brazil. soviero@compuland.com.br
authors.forename: Vera
authors.initials: V
authors.lastname: Soviero
authors.forename: Dorte
authors.initials: D
authors.lastname: Haubek
authors.forename: Carolina
authors.initials: C
authors.lastname: Trindade
authors.forename: Thais
authors.initials: T
authors.lastname: Da Matta
authors.forename: Sven
authors.initials: S
authors.lastname: Poulsen
mesh_terms: D000293:Adolescent; D001938:Brazil / Q000453:epidemiology; D002648:Child; D003743:Dental Enamel / Q000473:pathology*; D003744:Dental Enamel Hypoplasia / Q000453:epidemiology* / Q000473:pathology; D019229:Dentition, Permanent; D005260:Female; D006801:Humans; D007180:Incisor / Q000473:pathology*; D008297:Male; D008963:Molar / Q000473:pathology*; D015995:Prevalence; D017001:Tooth Demineralization / Q000453:epidemiology* / Q000473:pathology