title: Fatigue resistance and failure mode of CAD/CAM composite resin implant abutments restored with type III composite resin and porcelain veneers.
abstract: OBJECTIVE
  This study assessed the fatigue resistance and failure mode of type III porcelain and composite resin veneers bonded to custom composite resin implant abutments.
  
  
  METHODS
  Using the CEREC 3 machine, 28 composite resin implant abutments (Paradigm MZ100) were fabricated along with non-retentive type III veneers, milled either in ceramic Paradigm C (n=14) or in composite resin Paradigm MZ100 (n=14). The intaglio surfaces of the veneers were hydrofluoric acid etched and silanated (Paradigm C) or airborne-particle abraded and silanated (MZ100). The fitting surface of the abutments was airborne-particle abraded, cleaned, silanated and inserted into a bone level implant (10 mm, BLI RC). All veneers were luted with adhesive resin (Optibond FL) and a preheated light curing composite resin (Filtek Z100). Cyclic isometric chewing (5 Hz, 30° angle) was simulated, starting with a load of 40 N, followed by stages of 80, 120, 160, 200, 240 and 280 N (20,000 cycles each). Samples were loaded until fracture or to a maximum of 140,000 cycles. Groups were compared using the life table survival analysis (Log rank test at P=0.05). Previously published data using same-design zirconia abutments were included for comparison.
  
  
  RESULTS
  Paradigm C and MZ100 specimens fractured at an average load of 243 and 206 N (survival rate of 21% and 0%), respectively, with a significant difference in survival probability (P=0.02). Fractured specimens presented mixed failure modes and solely adhesive failures were not observed. The survival of composite resin abutments was similar to that of identical zirconia abutments from a previous study (P=0.76).
  
  
  CONCLUSIONS
  Non-retentive porcelain veneers bonded to custom composite resin implant abutments presented a higher survival rate when compared with composite resin veneers. Survival of composite resin abutment did not differ from zirconia ones.
authors: The Don & Sybil Harrington Foundation Chair of Esthetic Dentistry, Division of Restorative Sciences, The Herman Ostrow School of Dentistry, University of Southern California Los Angeles, CA 90089-7792, USA. magne@usc.edu
authors: Pascal
authors: P
authors: Magne
authors: Elisa
authors: E
authors: Oderich
authors: Luís Leonildo
authors: LL
authors: Boff
authors: Antônio Carlos
authors: AC
authors: Cardoso
authors: Urs Christoph
authors: UC
authors: Belser
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D001732:Bite Force; D002516:Ceramics / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D017076:Computer-Aided Design; D000044:Dental Abutments; D001840:Dental Bonding; D045662:Dental Etching / Q000379:methods; D015921:Dental Implants; D003764:Dental Materials / Q000737:chemistry*; D003776:Dental Porcelain / Q000737:chemistry*; D017267:Dental Prosthesis Design; D019232:Dental Restoration Failure; D003801:Dental Veneers; D006801:Humans; D006858:Hydrofluoric Acid / Q000737:chemistry; D008422:Materials Testing; D019279:Resin Cements / Q000737:chemistry; D012821:Silanes / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D013314:Stress, Mechanical; D016019:Survival Analysis; D015040:Zirconium / Q000737:chemistry
chemical_list: D003188:Composite Resins; D015921:Dental Implants; D003764:Dental Materials; C469607:OptiBond FL; D019279:Resin Cements; D012821:Silanes; C083568:Z100 composite resin; C452079:paradigm MZ100; D003776:Dental Porcelain; D012822:Silicon Dioxide; C023506:Glass ceramics; D015040:Zirconium; D006858:Hydrofluoric Acid