Should oral implants be splinted in a mandibular implant-supported fixed complete denture? A 3-dimensional-model finite element analysis.

Statement of Problem: The design of a mandibular fixed complete denture can influence periimplant bone loss. However, the design that transfers the greatest stress to the periimplant bone is not well documented.
Purpose: The purpose of this study was to assess the stress distribution associated with splinted and nonsplinted implant-supported mandibular fixed complete denture designs.
Material and Methods: Three-dimensional finite element models simulating 6 osseointegrated implants were created in the mandible to support a cobalt-chromium alloy and feldspathic porcelain veneering framework. One model simulated a 1-piece framework, and the other models simulated 2-piece and 3-piece frameworks. Axial and oblique loads were applied to the frameworks.
Results: For all the models, the greatest stress values were recorded in the periimplant bone of posterior implants, with differences between the left and right sides. The axial load transferred greater stress values to the periimplant bone than did the oblique load. The lowest periimplant bone stress values were observed in the 3-piece framework model at all implant locations, with the exception of implants placed in the canine region.
Conclusions: A framework separated into 3 pieces transfers the least stress to the periimplant bone.
(Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)