Aim: This study directed to compare different tooth-supported fixed dental prostheses "FDP" designs (pier abutment and cantilever designs) and their effect on stress distribution through using the restorative materials (PEEK, Zirconia, and Porcelain fused to metal).
Materials and methods: Three dimensional (3D) finite element models were constructed for both designs: pier abutment design and cantilever design. Different upper fixed dental prostheses, including the abutments (upper canine, premolar, and molar) and other components such as retainers, connectors, pontic, and gingiva were created in "Autodesk inventor" version 8 and then exported as SAT file. These components are assembled in an ANSYS environment (computer Intel Pentium Core 2 Duo. The proposed FDP materials are; Porcelain fused to metal (PFM), Zirconia, and Poly-Ether-Ether-Ketone (PEEK). Three finite element models were constructed. Pier abutment designs (conventional rigid connector fixed-fixed five units pier abutment) and cantilever designs (2 units & 3 units design). The study performed a total of nine runs (stress analysis and stress distribution). When the vertical loading was applied, three runs were done for each model (PFM, Zirconia, and PEEK restorative materials).
Results: Data were represented as Von Mises stress for the maximum value of stress. PFM, and Zirconia FDP behavior were comparable, while the PEEK one transferred much more load to FDP components and the underneath structures. Moreover, total deformation of bone was increased when using PEEK as "FDP" than with Zirconia, and PFM.
Conclusions: PEEK was liable to higher deformation and delivered unacceptable stress to surrounding vital structures such as the bone.