Stress Distribution Pattern in Mandibular Overdenture Designs Supported by Three Dental Implants: A 3D Finite Element Analysis Publisher Pubmed



Aminianpour N^{1, 2} ; Alikhasi M^{1, 2} ; Kasari MS^{3, 4} ; Yousefi H^{4, 5} ; Siadat H^{1, 2} Show Affiliations
Source: Clinical and Experimental Dental Research Published:2025

Abstract

Objectives: The purpose of this study was to assess the implant-supported overdenture stress distribution pattern in cancellous and cortical bone, dental implants, and prosthetic components, and its displacement by using finite element analysis (FEA). Materials and Methods: An edentulous model of the mandible was designed with three dental implants placed at the sites of canine teeth and the midline. Six groups were designed with isolated (ball and locator) and splinted (conventional bar and a CAD/CAM milled bar with cast and screw ball) attachments with and without a cantilever using SolidWorks 2022 software. The stress distribution pattern in the surrounding bone, implants, and prosthetic components (attachments, caps, housings, and screws) was evaluated following the application of 150 N force vertically and 105 N load with a 30° angle relative to the first molar site using Abaqus/CAE 2021 software. The implant-supported overdenture displacement was also evaluated. Results: The ball attachment caused the highest stress in the attachments (363 and 896 MPa) and housings (375 and 1187 MPa) under vertical and oblique loadings, and cancellous bone (6 MPa under vertical loading). The pattern of stress distribution was variable following vertical and oblique loading in the cortical bone and dental implants in different groups. The locator attachment resulted in lower stress distribution in bone, implants, and prosthetic components. In splinted groups, the cantilever designs caused lower stress in bone, implants, and prosthetic components in comparison with designs without a cantilever. The conventional and milled bar did not show any mechanical difference. Conclusion: Considering the stress distribution patterns, the locator attachment is preferred to the ball isolated attachment, and the cantilever design is preferred among the splinted types. Isolated attachments were more effective in controlling the displacement. Also, conventional and milled bars did not show any superiority over each other. © 2025 The Author(s). Clinical and Experimental Dental Research published by John Wiley & Sons Ltd.