Fracture Resistance of Titanium-Based Lithium Disilicate and Zirconia Implant Restorations

PurposeTo evaluate the fracture resistance of a newer lithium disilicate abutment material. Materials and MethodsA premolar-shaped implant crown was designed using CAD/CAM software, and four groups of implant and crown combinations were milled: (1) lithium-disilicate hybrid-abutment crown; (2) screwmentable lithium-disilicate hybrid abutment/lithium-disilicate crown with screw channel; (3) lithium-disilicate hybrid abutment/lithium-disilicate crown; and (4) zirconia hybrid abutment/lithium-disilicate crown (control). The specimens were cemented to a titanium-base implant system, subjected to thermocycling and cyclic loading, and fractured in a material testing device. ResultsThe lithium-disilicate hybrid-abutment crown had significantly greater fracture load than all the other groups, which were not significantly different from each other. ConclusionsBased on fracture load, the new lithium-disilicate hybrid-abutment material may serve as a viable alternative to the use of zirconia as a hybrid-abutment material.