Abstract:
Objective: The purpose of this study was to evaluate the stress distribution of fixed implant-supported prostheses using “all-on-four" concept for the treatment of mandibular completely edentulous ridge “in vitro study" by 3D finite elements analysis. Materials and Methods: The finite element model components as the overdenture, mucosa, implants, angled base, abutment, cortical and cancellous bones were created in "Autodesk Inventor, then exported as SAT files. These components were assembled in ANSYS environment. The model was subjected to two loading conditions of 200N, vertically unilateral and, vertically bilateral at molar regions respectively. Results: All values of deformations and stresses appeared on the model components (overdenture, implants, angled base, abutment, cortical and cancellous bones) were within physiological limits under all loads application. Conclusion: Tilted implants at molar area did not affect the system behavior (did not show peak of stresses or deformation) and all values of deformations and stresses that appeared on the model parts (cortical, spongy bone, implant, base, abutment, and overdenture) were within physiological limits under all cases of load application.