title: Survival rates of IPS empress 2 all-ceramic crowns and fixed partial dentures: results of a 5-year prospective clinical study.
abstract: OBJECTIVE
  The aim of this prospective clinical study was to evaluate the survival rates of IPS Empress 2 (Ivoclar Vivadent) all-ceramic crowns and fixed partial dentures (FPDs) after an observation period of up to 5 years.
  
  
  METHODS
  Forty-three patients (19 women and 24 men) were included in this study. The patients were treated with a total of 58 adhesive bonded IPS Empress 2 restorations. A total of 27 single crowns were placed on molars and premolars, and 31 three-unit FPDs were placed in the anterior and premolar regions. Clinical follow-up examinations took place at 6, 12, 24, 36, 48, and 60 months after insertion. Statistical analysis of the data was calculated using the Kaplan-Meier method.
  
  
  RESULTS
  Results of the 50-month analysis (interquartile range, 33 to 61 months) showed that the survival rate was 100% for crowns and 70% for FPDs. Six failures that occurred exclusively in the three-unit FPDs were observed. Framework fractures were recorded in three FPD units where the connector dimensions did not meet the manufacturer specifications. Only one FPD exhibited an irreparable partial veneer fracture, and 2 FPDs showed evidence of biologic failures. The accuracy of fit and esthetic parameters were clinically satisfactory for crowns and FPDs.
  
  
  CONCLUSIONS
  The results of this 5-year clinical evaluation suggest that IPS Empress 2 ceramic is an appropriate material for the fabrication of single crowns. Because of the reduced survival rates, strict conditions should be considered before the use of IPS Empress 2 material for the fabrication of three-unit FPDs.
authors.affiliation: Department of Prosthodontics, Dental School, University Clinic of Freiburg, Germany. pascal.marquardt@uniklinik-freiburg.de
authors.forename: Pascal
authors.initials: P
authors.lastname: Marquardt
authors.forename: Jörg Rudolf
authors.initials: JR
authors.lastname: Strub
mesh_terms: D000328:Adult; D000368:Aged; D003442:Crowns; D001840:Dental Bonding; D003776:Dental Porcelain / Q000737:chemistry*; D017269:Dental Prosthesis Repair; D017268:Dental Prosthesis Retention; D019232:Dental Restoration Failure; D003801:Dental Veneers; D003779:Denture Design; D003830:Denture, Partial, Fixed; D004955:Esthetics, Dental; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D018020:Lithium Compounds / Q000737:chemistry*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D019279:Resin Cements / Q000737:chemistry; D013499:Surface Properties; D016019:Survival Analysis; D019231:Tooth Preparation, Prosthodontic
chemical_list: C118557:Empress 2; D018020:Lithium Compounds; D019279:Resin Cements; D003776:Dental Porcelain; C103502:Variolink