title: A preliminary prospective evaluation of all-ceramic crown-retained and inlay-retained fixed partial dentures.
abstract: OBJECTIVE
  The purpose of this preliminary prospective study was to evaluate the clinical outcome of crown-retained and inlay-retained fixed partial dentures (FPDs) made from a new lithium-disilicate glass-ceramic (IPS e.max Press, Ivoclar Vivadent).
  
  
  METHODS
  Eighty-one 3-unit FPDs were placed in 68 patients. The FPDs replaced teeth in the anterior (8%) and posterior region (92%). All teeth were prepared according to a standardized protocol. The size of the proximal connector of the FPDs was 12 mm2 (anterior) or 16 mm2 (posterior), respectively. Crown-retained FPDs were cemented either with glass ionomer (n = 20) or resin composite (n = 16), while all inlay-retained FPDs (n = 45) were cemented with resin composite. Initial follow-up was performed at 6 and 12 months and annually thereafter.
  
  
  RESULTS
  The mean observation periods were 48 months (for crown-retained FPDs) and 37 months (for inlay-retained FPDs). None of the crown-retained FPDs failed during the observation period, while 6 inlay-retained FPDs (13%) had to be replaced. Six cases failed because of debonding (n = 3) or a combination of debonding and fracture (n = 3). During the observation period, 2 patients died and the status of another 5 patients is unknown. The 4-year survival rate according to Kaplan-Meier was 100% for crown-retained FPDs and 89% for inlay-retained FPDs. The differences between the groups were statistically significant.
  
  
  CONCLUSIONS
  Crown-retained 3-unit FPDs made from a new glass-ceramic have a significantly better outcome up to 5 years than inlay-retained 3-unit FPDs over the observation period.
authors.affiliation: Department of Prosthodontics, Propaedeutics and Dental Materials, School of Dentistry, Christian-Albrechts University, Kiel, Germany. swolfart@proth.uni-kiel.de
authors.forename: Stefan
authors.initials: S
authors.lastname: Wolfart
authors.forename: Frank
authors.initials: F
authors.lastname: Bohlsen
authors.forename: Stefan Martin
authors.initials: SM
authors.lastname: Wegner
authors.forename: Matthias
authors.initials: M
authors.lastname: Kern
mesh_terms: D000328:Adult; D000368:Aged; D002484:Cementation / Q000379:methods*; D003442:Crowns; D000044:Dental Abutments; D003776:Dental Porcelain; D019232:Dental Restoration Failure; D003779:Denture Design; D003781:Denture Retention / Q000379:methods*; D003830:Denture, Partial, Fixed; D005260:Female; D005899:Glass Ionomer Cements; D006801:Humans; D007284:Inlays; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D019279:Resin Cements; D018709:Statistics, Nonparametric; D016019:Survival Analysis
chemical_list: D005899:Glass Ionomer Cements; C508050:IPS e.max Press; D019279:Resin Cements; D003776:Dental Porcelain