title: Developmental defects of enamel in primary teeth - findings of a regional German birth cohort study.
abstract: BACKGROUND
  The aim was to assess the prevalence, distribution and associated risk factors of developmental defects of enamel (DDE) in 3-year-old Thuringian children in 2013 as part of a prospective cohort study.
  
  
  METHODS
  The subjects (n = 377) were all participants in a Thuringian oral health programme. Children of the birth cohort 2009/2010 were invited to dental examination in the first year of life, followed up with continuous dental care over the next 3 years. Dental caries was scored using the WHO diagnostic criteria expanded to the d1-level without radiography. Enamel defects were assessed according to the modified DDE Index. Data were analysed statistically (multivariate logistic regression).
  
  
  RESULTS
  The children were aged 3.3 ± 0.7 years and 52.5 % of them were male. Caries prevalence was 15.6 % and caries experience 0.9 ± 3.3 d1-4mfs. The prevalence of DDE was 5.3 % with an average of 2.7 (±1.4) affected teeth. Second primary molars were the most affected teeth and demarcated opacities the most prevalent type. No child had Amelogenesis imperfecta and six children showed hypomineralised second primary molars. Enamel defects were associated with preterm birth (p = 0.024; OR = 4.9) and hospitalisation in the first year of life (p = 0.013; OR = 4.6).
  
  
  CONCLUSIONS
  A relatively small proportion of 3-year-old Thuringian children suffered from DDE, with second primary molars as the most affected teeth and demarcated opacities as the most prevalent type of defect. Preterm birth and hospitalisation in first year of life can be considered as risk factors for DDE in the primary dentition.
  
  
  BACKGROUND
  German Clinical Trials Register, DRKS00003438.
authors.affiliation: Department of Preventive Dentistry and Pediatric Dentistry, Jena University Hospital, Bachstr. 18, Jena, Germany. Yvonne.Wagner@med.uni-jena.de.
authors.forename: Yvonne
authors.identifier: http://orcid.org/0000-0002-1184-2006
authors.initials: Y
authors.lastname: Wagner
mesh_terms: D002675:Child, Preschool; D003731:Dental Caries / Q000453:epidemiology*; D003743:Dental Enamel; D003744:Dental Enamel Hypoplasia; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence; D011446:Prospective Studies; D014094:Tooth, Deciduous
keywords: Enamel defects; Enamel hypomineralisation; Prevalence; Primary dentition