Parameters Influencing Fracture Strength in Implant-Supported Zirconia Restorations: A Scoping Review

Mechanical properties are considered key determinants of the long-term success of implant-supported zirconia restorations. However, limited data are available regarding the parameters that influence the fracture strength of implant-supported zirconia restorations. Generative design is well suited for the optimization in implant prosthodontics, as it allows the definition of a constrained design space and the application of optimization algorithms to evaluate numerous design iterations based on predefined biomechanical objectives. Prior to the implementation of generative design, it is essential to identify and define the parameters that influence the optimization of structures such as hybrid implant abutments. The parameters identified in this review will be incorporated into the parametric model and subsequently applied within the generative design workflow to facilitate the customization of hybrid implant abutments. A comprehensive literature search was conducted in the PubMed and Scopus databases to identify relevant studies published between 1 December 2025 and 1 May 2026. In vitro studies investigating fracture strength of implant-supported zirconia restorations were considered eligible for inclusion. A total of 12 studies met the eligibility criteria. Their findings indicated that implant-supported zirconia restorations generally withstood fracture loads exceeding the maximum masticatory forces reported in the oral environment, although the recorded values varied according to restoration design, abutment type, surface modifications, material thickness, retention type, material selection, luting agents, and interface characteristics.