Bending overload and implant fracture: a retrospective clinical analysis.

TLDR

Fracture frequency of implant‑supported prostheses in posterior regions is low, but this study shows that appropriate treatment planning can essentially prevent overload‑related failures. The authors retrospectively analyzed 39 patients with implant fractures to identify probable causes. Most fractures (90%) occurred in the posterior region, predominantly in prostheses supported by one or two implants subjected to cantilever load magnification and bruxism or heavy occlusal forces, indicating that such prostheses have an increased risk of bending overload.

Abstract

Thirty-nine patients with implant fractures treated by three of the authors have been analyzed as to probable causes. Thirty-five (90%) of the fractures occurred in the posterior region. Thirty (77%) of the prostheses were supported by one or two implants, which were exposed to a combination of cantilever load magnification and bruxism or heavy occlusal forces. It was concluded that prostheses supported by one or two implants and replacing missing posterior teeth are subjected to an increased risk of bending overload. The literature review indicates that the fracture frequency is low in these situations and this study demonstrates that with appropriate treatment planning, such overload situations can essentially be prevented.