Mechanical testing of four-unit implant-supported prostheses with extensive pink gingiva porcelain: The dentogingival prostheses proof of concept

Author(s)

Benalcazar Jalkh, Ernesto B. ; Neto, Juvenal de Souza ; Bergamo, Edmara T. P. ; Maia, Camila F. ; Bonfante, Estevam A.

• Document type: Journal article
• Source: Journal of Esthetic and Restorative Dentistry; v. 33, n. 4, p. 8-pg., 2021-01-10.

Abstract

Objective: To investigate the probability of survival and failure modes of four-unit implant-supported porcelain fused to metal (PFM) dentogingival prostheses subjected to step-stress accelerated life testing (SSALT). Materials and methods: Eighteen implant-supported PFM dentogingival prostheses with thin metallic infrastructures, which provided minimal ceramic support and improved esthetics were fabricated over external hexagonal connection UCLA abutments. SSALT was performed until specimen failure. Use level probability Weibull curve and reliability were calculated and plotted. Weibull modulus (m) and characteristic strength (eta) were also calculated. Polarized light microscope and scanning electron microscope were used to characterize fractures. Results: Failures were dictated by material strength rather than fatigue damage accumulation. The probability of survival for loads reaching 100 and 150 N in 100,000 cycles was 92 and 61%, respectively. No cracks or fractures were identified in the veneered porcelain, whereas abutment fixation screw fracture was the chief failure mode. Conclusion: Implant-supported PFM four-unit dentogingival prostheses with minimum metal framework dimensions presented favorable lifetime prediction under fatigue testing. Fractures were restricted to fixation screws. Clinical significance: In-vitro fatigue testing and failure mode analyses evidenced favorable lifetime prediction for 4-unit implant-supported dentogingival prostheses with minimum metal frameworks. Abutment fixation screw fracture might be the most frequent clinical complication. Since this proof of concept has been tested in-vitro, further studies including different restorative materials, as well as long-term clinical trials are warranted. (AU)

• FAPESP's process: 12/19078-7 - Development and processing of Al2O3-ZrO2 translucent composite for CAD/CAM monolithic prostheses: the effect of aging on biaxial flexural strength
• Grantee: Estevam Augusto Bonfante
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 16/18818-8 - Multi-User Equipment approved in grant 2012/19078-7: ElectroPuls E3000 Linear-Torsion All-Electric dynamic test instrument package
• Grantee: Estevam Augusto Bonfante
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 19/08693-1 - Experimental glass-infiltrated alumina-zirconia composites: characterization of microstructure, optical and mechanical properties.
• Grantee: Edmara Tatiely Pedroso Bergamo
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 19/00452-5 - EXPERIMENTAL 70%Al2O3-30%ZrO2 ZTA COMPOSITES: MECHANICAL, ESTRUCTURAL AND TOPHOGRAPHICAL CHARACTERIZATION
• Grantee: Ernesto Byron Benalcazar Jalkh
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• FAPESP's process: 18/03072-6 - Experimental 70% Al2O3-30% ZrO2 composites: structural characterization and survival probability before and after aging
• Grantee: Ernesto Byron Benalcazar Jalkh
• Support Opportunities: Scholarships in Brazil - Doctorate