Stress distribution on bone and implant by three-dimensional finite element analysis

Endosseous oral implants are used for orthodontic anchorage in subjects with multiple tooth agenesis. Their effectiveness under orthodontic loading has been demonstrated clinically and experimentally. This study examines three-dimensional (3D) finite element (FE) models for bone and implants. A numerical simulation of stress distributions around implants was used to determine the best length, diameter, screw type, screw pitch, and screw head for implants to dissipate stress. The model was applied to determine the pattern and distribution of stresses within the endosseous implant and on supporting tissues when the endosseous implant is used for orthodontic anchorage. A threaded implant was placed in an edentulous segment of a human mandible with cortical and cancellous bone. Analytical results demonstrate that maximum stresses were always located around the implant neck in marginal bone. Thus, this area should be preserved clinically to maintain the structure and function of a bone implant.