title: Selection of dental materials and longevity of replaced restorations in Public Dental Health clinics in northern Sweden.
abstract: OBJECTIVE
  To investigate the selection of direct restorative materials and longevity of replaced restorations in relation to operator and patients characteristics.
  
  
  METHODS
  A cross-sectional study of treatment in practice, recording all new placements and replacements of direct restorations was performed during 2 weeks comprising all dentists within the Public Dental Health clinics in the county council of Västerbotten.
  
  
  RESULTS
  A total of 2834 data collection sheets, one for each placed restoration, were received with a dropout of 10%. Restorations analyzed in the study were placed in permanent teeth in patients older than 15 years. First restorations placed due to primary caries were 671 and replacements 1536. Class II was the most frequently treated cavity followed by class I. The median longevity of replaced restorations was for amalgam, resin based composite and glass ionomer 16, 6 and 11 years, respectively. High caries risk patients showed shorter longevity for resin based composite restorations than low or moderate risk patients. Secondary caries as reason for failure for class II resin based composite restorations occurred significantly later than loss or fracture. Significantly longer longevity was observed for replaced restorations executed by more experienced dentists.
  
  
  CONCLUSIONS
  The use of amalgam was negligible and the material was predominantly replaced by resin based composites in first and replaced restorations. Class II was the most frequent placed and replaced restorations. Caries risk and experience of operator influenced longevity of replacements.
authors.affiliation: Department of Odontology, Umeå University, 901 87 Umeå, Sweden. Karin.Sunnegardh@odont.umu.se <Karin.Sunnegardh@odont.umu.se>
authors.forename: Karin
authors.initials: K
authors.lastname: Sunnegårdh-Grönberg
authors.forename: Jan W V
authors.initials: JW
authors.lastname: van Dijken
authors.forename: Ulrika
authors.initials: U
authors.lastname: Funegård
authors.forename: Anders
authors.initials: A
authors.lastname: Lindberg
authors.forename: Mats
authors.initials: M
authors.lastname: Nilsson
mesh_terms: D000328:Adult; D002983:Clinical Competence; D003188:Composite Resins; D003430:Cross-Sectional Studies; D003723:Dental Amalgam; D003731:Dental Caries / Q000628:therapy; D003737:Dental Cavity Preparation / Q000145:classification; D003740:Dental Clinics; D003763:Dental Leakage; D019232:Dental Restoration Failure; D003793:Dental Restoration, Permanent / Q000379:methods* / Q000706:statistics & numerical data*; D005260:Female; D005899:Glass Ionomer Cements; D006801:Humans; D008297:Male; D008875:Middle Aged; D011636:Public Health Dentistry; D019233:Retreatment; D013548:Sweden; D013997:Time Factors
chemical_list: D003188:Composite Resins; D005899:Glass Ionomer Cements; D003723:Dental Amalgam