title: A clinical evaluation of posterior composite restorations: 17-year findings.
abstract: OBJECTIVE
  Since an increasing number of composite restorations in posterior teeth are placed as a routine, this study was conducted to evaluate long-term survival of these restorations placed in general practice.
  
  
  METHODS
  Patients from a private dental office that received restorations in posterior teeth between 1987 and 1988 with P-50 (3M) or Herculite XR (Kerr) resin composites were selected and invited to participate. Restorations were placed under rubber dam isolation. Dentine walls were covered with glass ionomer cement, and composites were placed according to manufacturer's instructions. Thirty-eight patients agreed to participate and signed an informed consent prior to the evaluation. Two calibrated operators worked independently in the evaluation, using modified USPHS criteria. Survival of restorations or subsets of restorations grouped on the basis of variables (material, tooth, cavity type and size) was determined using Kaplan-Meier survival curves.
  
  
  RESULTS
  Ninety-eight failures were recorded among the 282 restorations providing a crude estimate of 34.8% failures. The survival rate was not significant for material (p=0.92) but was significant between tooth (lower premolars and lower molars, p<0.0001), cavity type (p<0.001) and size (p<0.001). The majority of restorations exhibited A or B scores for the evaluated criteria. The main failure cause was fracture of both composites.
  
  
  CONCLUSIONS
  The clinical performance of posterior resin composite restorations evaluated was acceptable after 17-year evaluation. However, the probability of failure of resin composite restorations in molars, Class II, and large restorations is higher.
authors.affiliation: Graduate Program in Dentistry, Cariology Area, Faculty of Dentistry of Piracicaba, State University of Campinas, Piracicaba, SP, Brazil.
authors.forename: Paulo Antônio
authors.initials: PA
authors.lastname: da Rosa Rodolpho
authors.forename: Maximiliano Sérgio
authors.initials: MS
authors.lastname: Cenci
authors.forename: Tiago Aurélio
authors.initials: TA
authors.lastname: Donassollo
authors.forename: Alessandro Dourado
authors.initials: AD
authors.lastname: Loguércio
authors.forename: Flávio Fernando
authors.initials: FF
authors.lastname: Demarco
mesh_terms: D000328:Adult; D001641:Bicuspid / Q000473:pathology; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding / Q000379:methods; D003737:Dental Cavity Preparation / Q000145:classification; D018772:Dental Marginal Adaptation; D019232:Dental Restoration Failure; D003793:Dental Restoration, Permanent / Q000145:classification / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D005899:Glass Ionomer Cements / Q000737:chemistry; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008689:Methacrylates / Q000737:chemistry; D008963:Molar / Q000473:pathology; D011140:Polyurethanes / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D013499:Surface Properties; D016019:Survival Analysis
chemical_list: D003188:Composite Resins; D005899:Glass Ionomer Cements; D008689:Methacrylates; D011140:Polyurethanes; D019279:Resin Cements; C065770:Herculite XR; C065771:P50 composite resin; C067788:scotchbond 2; C070604:XR Bond; D017438:Bisphenol A-Glycidyl Methacrylate