Biomechanical three-dimensional finite-element analysis of maxillary prostheses with implants. Design of number and position of implants for maxillary prostheses after hemimaxillectomy.

The present study analyzed stress distributions in craniofacial structures around implant-supported maxillary prostheses. Using post-hemimaxillectomy computed tomography (CT) of a patient, the authors constructed a three-dimensional (3D) solid model using Digital Imaging and Communications in Medicine data (DICOM data) for maxillofacial and cranial bones. The effects of different prosthesis designs on stress distributions in craniofacial bones and osseous tissues around the implants were biomechanically investigated using 3D finite-element analysis. Maxillary prostheses were designed with 2 implants in the zygoma on the affected side and 2-3 implants in the maxillary alveolar bone on the unaffected side, without using a cantilever. Zygomatic implants provided suitable stress dispersal to the zygomatic and craniofacial bones on the affected side. This information is useful for designing maxillary prostheses.