Occlusal Overload

According to the Glossary of Oral and Maxillofacial Implants, occlusal overload is defined as “the application of occlusal loading, through function or parafunction, in excess of what the prosthesis, implant component, or osseointegrated interface is capable of withstanding without structural or biologic damage.”¹⁶ The rigid bone-implant interface, combined with the crestal fulcrum (generated by lateral forces), concentrates stress in the crestal region, thereby subjecting peri-implant bone to excessive loading.^5,9 Several studies have suggested that occlusal overload in implants may result in biological complications such as marginal bone loss and implant failure, and/or mechanical complications such as screw loosening or fracture, veneering material failure, prosthesis fracture, and/or implant fracture.^17-19

However, the direct association between implant occlusal overload and peri-implant tissue loss remains controversial due to the lack of long-term clinical studies and randomized controlled trials in humans.^4,20,21 Current scientific evidence suggests that occlusal overload may contribute to peri-implant tissue loss in the presence of inflammation; however, this relationship is less significant in clinically healthy peri-implant tissues.^4,21 Occlusal overload is therefore considered a potential risk factor for peri-implantitis in the presence of plaque and inflammation.^4,21 Given the potential biological and mechanical complications associated with occlusal overload, it is essential to recognize the risk factors that predispose implants to excessive loading and to implement strategies that help control or minimize these forces.