title: Impact of caries onset on number and distribution of new lesions in preschool children.
abstract: BACKGROUND
  Caries in preschool children remains an important public health issue.
  
  
  OBJECTIVE
  To determine (i) which teeth and tooth surfaces are most susceptible to dental caries by age 3, (ii) where do caries lesions develop during 2-year follow-up, and (iii) to evaluate the impact of caries onset on the distribution of new caries experience.
  
  
  METHODS
  One thousand and fifty seven consecutively born children were recruited in Flanders (Belgium). Parents completed validated questionnaires on oral health-related behaviour and trained dentists examined the children at ages 3 and 5.
  
  
  RESULTS
  Children with visible caries experience at age 3 were significantly more vulnerable in developing additional caries during follow-up. In this group, new caries experience developed primarily in the occlusal and distal surfaces of the mandibular first molars and the occlusal surfaces of the maxillary second and first molars, whereas in the caries-free group, the occlusal surfaces of both mandibular and maxillary second molars ranked first.
  
  
  CONCLUSIONS
  This paper confirms the higher vulnerability for further caries development in those children with caries experience at age 3. Visible caries develops most frequently in the occlusal surfaces of the second molars: in high-risk children already by age 3 and in children who were caries free at baseline by age 5.
authors.affiliation: Department of Oral Health Sciences, KU Leuven, Belgium. roos.leroy@med.kuleuven.be
authors.forename: Roos
authors.initials: R
authors.lastname: Leroy
authors.forename: Dominique
authors.initials: D
authors.lastname: Declerck
mesh_terms: D001530:Belgium; D002675:Child, Preschool; D004245:DMF Index; D003731:Dental Caries / Q000145:classification* / Q000503:physiopathology; D003733:Dental Caries Susceptibility / Q000502:physiology*; D003743:Dental Enamel / Q000473:pathology; D003804:Dentin / Q000473:pathology; D004522:Educational Status; D005500:Follow-Up Studies; D015438:Health Behavior; D006801:Humans; D007180:Incisor / Q000473:pathology; D008963:Molar / Q000473:pathology; D009909:Oral Health; D010290:Parents / Q000193:education; D018570:Risk Assessment; D012923:Social Class; D019228:Tooth Crown / Q000473:pathology