The implant-supported telescopic prosthesis: a biomechanical analysis.

This in vitro project investigated load transfer through screw-retained telescopic prostheses. Three Brånemark System implants incorporating strain gauges were embedded in an aluminum block. Telescopic prostheses that included 1 mesial and 1 distal cantilever were fabricated over 1 central EsthetiCone and 2 Ti-Adapt abutments. The buffering capacity of the cement in a combined screw-retained/cemented prosthesis was studied. The degree of misfit of the prostheses could be adjusted by applying shims of various thicknesses under the EsthetiCone. Load distribution was measured while a 50-N load was applied in turn over each implant and each cantilever. The results showed that tightening the central prosthetic screw widened the load distribution. The cement accommodated misfits between the layers of the telescope, significantly reducing bending moments on some supporting implants. The system exhibited a degree of tolerance to misfit and can provide a versatile prosthodontic option.