title: A practice-based research network on the survival of ceramic inlay/onlay restorations.
abstract: OBJECTIVE
  To evaluate prospectively the longevity of ceramic inlay/onlay restorations placed in a web-based practice-based research network and to investigate risk factors associated with restoration failures.
  
  
  METHODS
  Data were collected by a practice-based research network called Ceramic Success Analysis (CSA). 5791 inlay/onlay ceramic restorations were placed in 5523 patients by 167 dentists between 1994 and 2014 in their dental practices. For each restoration specific information related to the tooth, procedures and materials used were recorded. Annual failure rates (AFRs) were calculated and variables associated with failure were assessed by a multivariate Cox-regression analysis with shared frailty.
  
  
  RESULTS
  The mean observation time was 3 years (maximum 15 years) of clinical service, and AFRs at 3 and 10 years follow up were calculated as 1.0% and 1.6%. Restorations with cervical outline in dentin showed a 78% higher risk for failure compared to restorations with margins in enamel. The presence of a liner or base of glass-ionomer cement resulted in a risk for failure twice as large as that of restorations without liner or base material. Restorations performed with simplified adhesive systems (2-step etch-and-rinse and 1-step self-etch) presented a risk of failure 142% higher than restorations performed with adhesives with bonding resin as a separate step (3-step etch-and-rinse and 2-step self-etch). 220 failures were recorded and the most predominant reason for failure was fracture of the restoration or tooth (44.5%).
  
  
  CONCLUSIONS
  Ceramic inlay/onlay restorations made from several glass ceramic materials and applied by a large number of dentists showed a good survival. Deep cervical cavity outline, presence of a glass ionomer lining cement, and use of simplified adhesive systems were risk factors for survival.
authors.affiliation: Graduate Program in Dentistry, School of Dentistry, Federal University of Pelotas, Pelotas, RS, Brazil; Department of Dentistry, Radboud University Medical Center, Nijmegen, The Netherlands. Electronic address: kauecollares@gmail.com.
authors.forename: Kauê
authors.initials: K
authors.lastname: Collares
authors.affiliation: Graduate Program in Dentistry, School of Dentistry, Federal University of Pelotas, Pelotas, RS, Brazil.
authors.forename: Marcos B
authors.initials: MB
authors.lastname: Corrêa
authors.affiliation: Department of Dentistry, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Mark
authors.initials: M
authors.lastname: Laske
authors.affiliation: Dental Practice, Norden, Germany.
authors.forename: Enno
authors.initials: E
authors.lastname: Kramer
authors.affiliation: German Society of Computerized Dentistry, Berlin, Germany.
authors.forename: Bernd
authors.initials: B
authors.lastname: Reiss
authors.affiliation: Graduate Program in Dentistry, School of Dentistry, Federal University of Pelotas, Pelotas, RS, Brazil.
authors.forename: Rafael R
authors.initials: RR
authors.lastname: Moraes
authors.affiliation: Department of Dentistry, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Marie-Charlotte D N J M
authors.initials: MC
authors.lastname: Huysmans
authors.affiliation: Department of Dentistry, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Niek J M
authors.initials: NJ
authors.lastname: Opdam
mesh_terms: D002516:Ceramics; D019232:Dental Restoration Failure; D003793:Dental Restoration, Permanent; D017220:Dentin-Bonding Agents; D005899:Glass Ionomer Cements; D006801:Humans; D007284:Inlays; D019279:Resin Cements
chemical_list: D017220:Dentin-Bonding Agents; D005899:Glass Ionomer Cements; D019279:Resin Cements
keywords: Adhesives; Ceramic; Clinical trial; Inlays; Longevity; Prospective studies; Survival