Digital technique for anatomic design and bone-implant interface analysis of a custom bar for a mandibular implant-supported fixed dental prosthesis.

With the evolution of computer-aided design and computer-aided manufacturing (CAD-CAM), the digitally guided fabrication of implant-supported fixed dental prostheses has become increasingly precise and customized. Conventional substructure designs may fail to ensure a passive fit or adequate biomechanical performance in edentulous patients with severe mandibular bone resorption. Anatomic limitations and load concentration at the bone-implant interface present significant challenges for long-term prosthetic success. This article describes a step-by-step digital technique for designing a custom bar for a mandibular implant-supported prosthesis using cone beam computed tomography, 3-dimensional anatomic reconstruction with segmentation software program, and CAD tools. The design was biomechanically validated through finite element analysis to evaluate stress distribution and deformation under functional loading. This workflow enables clinicians and dental laboratory technicians to preclinically optimize the geometry and material behavior of the substructure, enhancing predictability and reducing complications in complete arch mandibular rehabilitation.