title: Longevity and reasons for failure of sandwich and total-etch posterior composite resin restorations.
abstract: OBJECTIVE
  To investigate longevity and reasons for failure of Class II posterior composite restorations (PCRs) placed with or without a lining of glass-ionomer cement.
  
  
  METHODS
  Four hundred fifty-eight Class II PCR placed in 248 patients (110 male, 138 female, age 18 to 80) by two dentists in a general practice between 1988 and 1997 were retrospectively examined from the patient files. The restorations were placed either with a total-etch technique or with a resin-modified glass-ionomer lining placed on the dentin. Items recorded were date of placement, date of last check-up visit, tooth number, and restored surfaces. Date of replacement and reason for failure of the PCR was recorded. A restoration was clinically acceptable when still in function and acceptable at the last check-up visit. Additionally, the caries risk for each patient was estimated by the treating clinician. Life tables and Kaplan-Meier curves were used to express survival rates. A Cox regression was applied to assess the influence of variables on survival.
  
  
  RESULTS
  Three hundred seventy-six total-etch PCRs and 82 PCRs with a lining were investigated. After 9 years, survival percentages of 88.1% for total-etch restorations and 70.5% for restorations with a resin-modified glass-ionomer lining were found. The most important reasons for failure were fracture and caries. Predominantly, failures started occurring after 3 to 4 years of clinical service. Results of the Cox regression show that the presence of a lining and high risk for caries significantly increased the failure rate of the restorations.
  
  
  CONCLUSIONS
  PCRs placed with a resin-modified glass-ionomer lining clinically showed more frequent fractures than PCRs placed with a total-etch technique.
authors.affiliation: Department of Preventive and Curative Dentistry, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands. n.opdam@dent.umcn.nl
authors.forename: Niek J M
authors.initials: NJ
authors.lastname: Opdam
authors.forename: Ewald M
authors.initials: EM
authors.lastname: Bronkhorst
authors.forename: Joost M
authors.initials: JM
authors.lastname: Roeters
authors.forename: Bas A C
authors.initials: BA
authors.lastname: Loomans
mesh_terms: D000134:Acid Etching, Dental; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001641:Bicuspid; D003188:Composite Resins; D003731:Dental Caries; D003736:Dental Cavity Lining; D019232:Dental Restoration Failure; D003793:Dental Restoration, Permanent / Q000379:methods*; D017220:Dentin-Bonding Agents; D005260:Female; D005899:Glass Ionomer Cements; D006801:Humans; D053208:Kaplan-Meier Estimate; D015993:Life Tables; D008297:Male; D008875:Middle Aged; D008963:Molar; D016016:Proportional Hazards Models; D019279:Resin Cements; D012189:Retrospective Studies
chemical_list: D003188:Composite Resins; D017220:Dentin-Bonding Agents; D005899:Glass Ionomer Cements; D019279:Resin Cements; C074669:Clearfil Photo Bond