Implant-Supported Vs. Tissue-Supported Prosthesis: Biomechanical Principles for Fixed Full-Arch Restorations

When treatment planning fully edentulous patients or those with terminal dentition, it is prudent for the implant team to review the support mechanism of the planned final prosthesis with both the patient and the treating team members. Two types of prosthetic designs are available for the fully edentulous arch: an implant-supported prosthesis and a tissue-supported prosthesis. The benefit of an implant-supported prosthesis is that residual bony volume is maintained by internal loading of the bone in centric occlusion. With a tissuesupported prosthesis there is absence of internal loading of the alveolus under function, leading to continuous resorption of alveolar bony volume. In treatment planning this group of patients, the differences between the two types of prostheses, as well as the anatomic limitations of the edentulous maxilla and mandible, should be taken into account to enable the optimal choice of number and distribution of implants for proper support of the final prosthesis. This article presents two cases describing an edentulous fixed treatment concept, one a maxillary case and the other a mandibular case.