title: All-ceramic or metal-ceramic tooth-supported fixed dental prostheses (FDPs)? A systematic review of the survival and complication rates. Part I: Single crowns (SCs).
abstract: OBJECTIVE
  To assess the 5-year survival of metal-ceramic and all-ceramic tooth-supported single crowns (SCs) and to describe the incidence of biological, technical and esthetic complications.
  
  
  METHODS
  Medline (PubMed), Embase, Cochrane Central Register of Controlled Trials (CENTRAL) searches (2006-2013) were performed for clinical studies focusing on tooth-supported fixed dental prostheses (FDPs) with a mean follow-up of at least 3 years. This was complimented by an additional hand search and the inclusion of 34 studies from a previous systematic review [1,2]. Survival and complication rates were analyzed using robust Poisson's regression models to obtain summary estimates of 5-year proportions.
  
  
  RESULTS
  Sixty-seven studies reporting on 4663 metal-ceramic and 9434 all-ceramic SCs fulfilled the inclusion criteria. Seventeen studies reported on metal-ceramic crowns, and 54 studies reported on all-ceramic crowns. Meta-analysis of the included studies indicated an estimated survival rate of metal-ceramic SCs of 94.7% (95% CI: 94.1-96.9%) after 5 years. This was similar to the estimated 5-year survival rate of leucit or lithium-disilicate reinforced glass ceramic SCs (96.6%; 95% CI: 94.9-96.7%), of glass infiltrated alumina SCs (94.6%; 95% CI: 92.7-96%) and densely sintered alumina and zirconia SCs (96%; 95% CI: 93.8-97.5%; 92.1%; 95% CI: 82.8-95.6%). In contrast, the 5-year survival rates of feldspathic/silica-based ceramic crowns were lower (p<0.001). When the outcomes in anterior and posterior regions were compared feldspathic/silica-based ceramic and zirconia crowns exhibited significantly lower survival rates in the posterior region (p<0.0001), the other crown types performed similarly. Densely sintered zirconia SCs were more frequently lost due to veneering ceramic fractures than metal-ceramic SCs (p<0.001), and had significantly more loss of retention (p<0.001). In total higher 5 year rates of framework fracture were reported for the all-ceramic SCs than for metal-ceramic SCs.
  
  
  CONCLUSIONS
  Survival rates of most types of all-ceramic SCs were similar to those reported for metal-ceramic SCs, both in anterior and posterior regions. Weaker feldspathic/silica-based ceramics should be limited to applications in the anterior region. Zirconia-based SCs should not be considered as primary option due to their high incidence of technical problems.
authors.affiliation: Division for Fixed Prosthodontics and Biomaterials, Center of Dental Medicine, University of Geneva, Geneva, Switzerland. Electronic address: Irena.sailer@unige.ch.
authors.forename: Irena
authors.initials: I
authors.lastname: Sailer
authors.affiliation: Division for Fixed Prosthodontics and Biomaterials, Center of Dental Medicine, University of Geneva, Geneva, Switzerland.
authors.forename: Nikolay Alexandrovich
authors.initials: NA
authors.lastname: Makarov
authors.affiliation: Department of Fixed and Removable Prosthodontics and Dental Material Science, University of Zurich, Switzerland.
authors.forename: Daniel Stefan
authors.initials: DS
authors.lastname: Thoma
authors.affiliation: Department of Social and Preventive Medicine, University of Berne, Berne, Switzerland.
authors.forename: Marcel
authors.initials: M
authors.lastname: Zwahlen
authors.affiliation: Department of Reconstructive Dentistry, Faculty of Odontology, University of Iceland, Reykjavik, Iceland.
authors.forename: Bjarni Elvar
authors.initials: BE
authors.lastname: Pjetursson
mesh_terms: D002516:Ceramics / Q000737:chemistry*; D003442:Crowns; D017267:Dental Prosthesis Design; D019094:Dental Prosthesis, Implant-Supported; D019232:Dental Restoration Failure; D004955:Esthetics, Dental; D006801:Humans; D016876:Metal Ceramic Alloys / Q000737:chemistry; D008670:Metals / Q000737:chemistry*
chemical_list: D016876:Metal Ceramic Alloys; D008670:Metals
keywords: All-ceramic; Biological complications; Complication rates; Failures; Longitudinal; Single crowns; Success; Survival; Systematic review; Technical complications