title: Sealing, refurbishment and repair of Class I and Class II defective restorations: a three-year clinical trial.
abstract: BACKGROUND
  The authors conducted a clinical study to examine the effectiveness of treatments other than replacement for defective Class I and Class II resin-based composite (RBC) and amalgam (AM) restorations.
  
  
  METHODS
  The authors recruited 66 patients (age range, 18-80 years) with 271 Classes I and II defective restorations (RBC = 78 and AM = 193). They assigned restorations to one of the following treatment groups on the basis of the type of defect: sealed margins (n = 48), repair (n = 27), refurbishment (n = 73), replacement (n = 42) or untreated (n = 81). They used modified U.S. Public Health Service/Ryge criteria to determine the quality of the restorations. Two examiners assessed the restorations independently at the beginning of the study and three years after treatment (Cohen's kappa = 0.74 at baseline and 0.82 at year 3). They used five parameters in assessing the restorations: marginal adaptation, anatomical form, surface roughness, secondary caries and luster.
  
  
  RESULTS
  The authors assessed 237 restorations (RBC = 73, AM = 164) at the three-year recall examination. Restorations that underwent sealing of marginal defects exhibited significant improvements in marginal adaptation (P <or= .001). Restorations in the refurbishment group exhibited improvements in anatomical form (P <or= .005) and surface roughness (P <or= .001). Restorations in the repair group exhibited improvements with regard to anatomical form (P = .008). Replaced restorations exhibited improvements in all parameters (P < .05), while the untreated group experienced declines in all parameters (P <.05).
  
  
  CONCLUSIONS
  The results of this study show that defective RBC and AM Class I and Class II restorations undergoing sealing of margins, repair or refurbishment exhibited improvements three years after treatment.
  
  
  CONCLUSIONS
  Marginal sealing or repair or refurbishment of anatomical form and roughness are conservative and simple procedures that increase the longevity of RBC and AM restorations with minimal intervention.
authors.affiliation: Department of Restorative Dentistry, Faculty of Dentistry, University of Chile, Santiago.
authors.forename: Gustavo
authors.initials: G
authors.lastname: Moncada
authors.forename: Javier
authors.initials: J
authors.lastname: Martin
authors.forename: Eduardo
authors.initials: E
authors.lastname: Fernández
authors.forename: Marie C
authors.initials: MC
authors.lastname: Hempel
authors.forename: Ivar A
authors.initials: IA
authors.lastname: Mjör
authors.forename: Valeria V
authors.initials: VV
authors.lastname: Gordan