A mimic osseointegrated implant model for three-dimensional finite element analysis

The purpose of this study was to develop a new three-dimensional (3D) mimic model of an osseointegrated implant for finite element analysis (FEA) and to evaluate stress distributions in comparison with a model commonly used in most studies as a control. Based on the 3D computer graphic data obtained by serial in vivo bucco-lingual peri-implant bone structure at 75 microm interval in monkey, a mimic FEA model with trabecular structure and a control model with uniform cancellous bone were constructed. A vertical load of 143 N was applied at the top of the implant and induced stress was evaluated at the peri-implant bone. In the mimic model, stress was distributed at both cortical and cancellous bones (1-5 MPa) in bucco-lingual central planes, but concentrated at the cortical crest (3-7 MPa) in the mesio-distal central plane. In contrast, the control model presented stress concentration at the cortical crest around the implant (5-14 MPa), with less stress (0-1 MPa) at the peri-implant cancellous bone in both planes. The findings, that stress distribution at the peri-implant bone were quite different between the mimic and control models, suggest the need to carefully interpret stress distribution in previous studies with models of uniform cancellous peri-implant bone.