Purpose: To assess whether material choice for the prosthetic component of an implant restoration influences the failure mode in case of occlusal overload in monolithic restorations fabricated from high-strength ceramics on titanium implants.
Materials and Methods: Within this pilot study, finite element analysis (FEA) was conducted to simulate stress and deformation of implant-supported crowns fabricated from lithium disilicate (LiS2) and zirconia (3Y-TZP). Additionally, an in vitro load-to-failure test was conducted using two specimens per group to evaluate the failure mode and to confirm the findings from the FEA. Results/
Conclusion: FEA revealed stress areas at the palatal cervical areas of the crowns. In the load-to-failure test, both LiS2 hybrid abutment crowns fractured (410 N and 510 N) before plastic deformation of the metal implant components could be detected. The 3Y-TZP monolithic hybrid abutment crowns did not fracture until the tests were interrupted at 646-N and 690-N occlusal force, when plastic deformation of the metal implant components was visually observed.
