title: Zirconia in fixed implant prosthodontics.
abstract: BACKGROUND
  CAD/CAM technology in combination with zirconia ceramic has increasingly gained popularity in implant dentistry.
  
  
  OBJECTIVE
  This narrative review presents the current knowledge on zirconia utilized as framework material for implant-borne restorations and implant abutments, laboratory tests and developments, clinical performance, and possible future trends for implant dentistry are addressed.
  
  
  METHODS
  A review of available literature from 1990 through 2010 was conducted with search terms zirconia,""implants,""abutment,""crown," and "fixed dental prosthesis" using electronic databases (PubMed) and manual searching.
  
  
  RESULTS
  Latest applications of zirconia in implant dentistry include implant abutments, multiple unit and full-arch frameworks as well as custom-made bars to support fixed and removable prostheses. High biocompatibility, low bacterial surface adhesion as well as favorable chemical properties of zirconia ceramics are reported. Zirconia stabilized with yttrium oxide exhibits high flexural strength and fracture toughness due to a transformation toughening mechanism. Preliminary clinical data confirmed the high stability of zirconia for abutments and as a framework material for implant borne crowns and fixed dental prostheses. Zirconia abutment or framework damage has rarely been encountered. However, veneering porcelain fractures are the most common technical complication in implant-supported zirconia restorations. These porcelain veneer failures have led to concerns regarding differences in coefficient of thermal expansions between core and veneering porcelain and their respective processing techniques.
  
  
  CONCLUSIONS
  As presently evidence of clinical long-term data is missing, caution with regard to especially extensive implant-borne zirconia frameworks is recommended.
authors.affiliation: Department of Prosthodontics, Dental School, Albert-Ludwigs University, Freiburg, Germany. petra.guess@uniklinik-freiburg.de
authors.forename: Petra Christine
authors.initials: PC
authors.lastname: Guess
authors.forename: Wael
authors.initials: W
authors.lastname: Att
authors.forename: Joerg Rudolf
authors.initials: JR
authors.lastname: Strub
mesh_terms: D017076:Computer-Aided Design; D003442:Crowns; D000044:Dental Abutments; D003776:Dental Porcelain / Q000737:chemistry; D017267:Dental Prosthesis Design; D019094:Dental Prosthesis, Implant-Supported; D019232:Dental Restoration Failure; D003799:Dental Stress Analysis; D003801:Dental Veneers; D003830:Denture, Partial, Fixed; D006358:Hot Temperature; D006801:Humans; D015019:Yttrium; D015040:Zirconium
chemical_list: C499362:yttria stabilized tetragonal zirconia; D003776:Dental Porcelain; D015019:Yttrium; D015040:Zirconium