Occlusion in Implant-Supported Fixed Partial Restorations: Biological Basis, Biomechanical Considerations and Clinical Recommendations

Background/Objectives: The management of occlusion in implant-supported fixed partial restorations (ISFPRs) remains a controversial topic due to the limited availability of high-level clinical evidence and the biomechanical differences between natural teeth and dental implants. The absence of the periodontal ligament and the altered biomechanics of implants have led to the development of specific occlusal concepts. This narrative review provides an up-to-date overview of the biological basis and biomechanical principles underlying occlusal management in ISFPRs, with a particular focus on translating these into clinically applicable recommendations. Methods: A narrative review was conducted using an electronic search of PubMed/MEDLINE, covering the period from 1 March 2001, to 1 March 2026. Clinical studies and review articles were included, along with in vitro studies and finite element analyses when relevant to the biomechanical principles of implant occlusion. Additional publications were selectively included to provide biological, biomechanical, historical, and prosthetic context. Results: The available literature indicates that the evidence supporting specific occlusal protocols for ISFPRs remains limited and heterogeneous. Contemporary occlusal concepts emphasize the minimization of non-axial loads, the optimization of occlusal morphology, the control of cantilever extension, and the consideration of patient-specific factors, such as bruxism. Monolithic zirconia represents a viable restorative option due to its favorable mechanical properties and reduced technical complications. Long-term maintenance and periodic reevaluation of the occlusion remain essential, as occlusal relationships continue to change throughout a patient’s lifetime. Conclusions: Although numerous occlusal concepts have been proposed, high-level scientific evidence remains limited. Clinicians should adopt individualized occlusal strategies based on sound biological and biomechanical principles and tailored to each patient’s specific functional needs and risk factors. The dynamic nature of occlusion in ISFPRs necessitates periodic reevaluation as an integral part of long-term maintenance. Further well-designed clinical studies are needed to establish evidence-based occlusal protocols specific to ISFPRs.