Fatigue resistance and failure mode of novel-design anterior single-tooth implant restorations: influence of material selection for type III veneers bonded to zirconia abutments.
OBJECTIVE
This study assessed the fatigue resistance and failure mode of type III porcelain and composite resin veneers bonded to custom zirconia implant abutments.


METHODS
Twenty-four standardized zirconia implant abutments were fabricated. Using the CEREC 3 machine, type III veneers of standardized shape were milled in ceramic Vita Mark II or in composite resin Paradigm MZ100. The intaglio surfaces of the restorations were hydrofluoric acid etched and silanated (Mark II) or airborne-particle abraded and silanated (MZ100). The fitting surface of the abutments was airborne-particle abraded, cleaned, and inserted into a bone level implant (BLI RC SLActive 10 mm). All veneers (n=24) were adhesively luted with a zirconia primer (Z-Prime Plus), adhesive resin (Optibond FL) and a pre-heated light-curing composite resin (Filtek Z100). Cyclic isometric chewing (5 Hz) 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 (Logrank test at P=.05).


RESULTS
Mark II and MZ100 specimens fractured at an average load of 216 N and 229 N (survival rate of 17% and 8%), respectively, with no difference in survival probability (P=.18). Among the fractured samples, 40% of the failures were at the abutment level for Mark II and 27% were at the abutment level for MZ100. No exclusive adhesive failures were observed.


CONCLUSIONS
Type III Mark II and Paradigm MZ100 veneers showed similar fatigue resistance when bonded to custom non-retentive zirconia implant abutments. The bond was strong enough to induce abutment fractures. MZ100 presented a higher percentage of "friendly" failures, i.e. maintaining the restoration-abutment adhesive interface and the abutment itself intact.
Division of Restorative Sciences, School of Dentistry, University of Southern California, 3151 S. Hoover St., Los Angeles, CA 90089-7792, USA. magne@usc.edu
Pascal
P
Magne
Maria Paula Gandolfi
MP
Paranhos
Luiz Henrique
LH
Burnett
Michel
M
Magne
Urs Christoph
UC
Belser
D003188:Composite Resins / Q000737:chemistry; D017076:Computer-Aided Design; D000044:Dental Abutments; D019250:Dental Implants, Single-Tooth; D003776:Dental Porcelain / Q000737:chemistry*; D017267:Dental Prosthesis Design; D019232:Dental Restoration Failure; D003799:Dental Stress Analysis; D003801:Dental Veneers; D008422:Materials Testing; D008689:Methacrylates; D013499:Surface Properties; D015040:Zirconium / Q000737:chemistry*
D003188:Composite Resins; D008689:Methacrylates; C082340:Vita Mark II; C000613955:Z-Prime Plus; C452079:paradigm MZ100; D003776:Dental Porcelain; D015040:Zirconium