Finite element analysis of an endoprosthesis.

Abstract

To determine the efficacy of a newly designed modular endoprosthesis for mandibular defect reconstruction in patients, finite element analysis (FEA), a mechanical and mathematical modeling technique, was conducted on a three-dimensional (3D) finite element mesh of a reconstructed macaque mandible inserted with the implant. FEA was also performed on the intact macaque mandible and endoprosthesis separately, to analyze their mechanical response to various static bite tasks. A 3D mesh model for the intact mandible was created using a software, Mimics 12.11, based on computerized tomography (CT) scan images, while a 3D volume of the endoprosthesis was modeled and subsequently meshed in ANSYS 11.0. Manual editing was utilized to create a defect within the mandible; the mesh of the defective mandible was then imported into ANSYS for insertion of the 3D endoprosthesis mesh. Results of FEA under different loading conditions were based on displacement, stress and strain distribution patterns within the meshed models. The results for the intact mandible helped gain better insight into the biomechanics of the macaque mandible, much of which is lacking in the available literature. FEA on the reconstructed mandible also highlighted potential high stress concentration sites that may lead to failure of the reconstructed system. Comparison of the biomechanics of the macaque mandible with that of the human can determine the usefulness of transferring these results onto a human mandibular system, and help predict the actual biological scenario for a patient’s mandible reconstructed with the new endoprosthesis.