A 3D Finite Element Analysis of a Tooth Restored with High Performance Polymer Post-Core System

Objectives: The aim of this study was to evaluate the biomechanical behavior and long-term safety of high performance polymer PEKK as an intraradicular dental post-core material through comparative finite element analysis (FEA) with other conventional post-core materials.
Methods: A 3D FEA model of a maxillary central incisor was constructed. A cyclic loading force of 50N was applied at an angle of 45 degree to the longitudinal axis of the tooth at the palatal surface of the crown. For comparison with traditionally used post-core materials, three materials (gold, fiberglass, and PEKK) were simulated to determine their post-core properties.
Results: PEKK, with a lower elastic modulus than root dentin, showed comparably high failure resistance and a more favorable stress distribution than conventional post-corematerial.However, the PEKK post-core system showed a higher probability of debonding and crown failure under long-term cyclic loading than the metal or fiberglass post-core systems.
Conclusions: (1) Although PEKK has a significantly lower elasticmodulus and flexural strength than metal and fiberglass, the use of PEKK as a dental post-core system showed potentially high fracture resistance compared to that of metal and fiberglass post-core systems.
(2) PEKK post-core, with the lower elastic modulus than dentine, exhibited a favorable stress distribution profile at the intraradicular surface, indicating a lower possibility of root fracture than for conventional postcore materials.
(3) Since PEKK transferred higher stresses to the interface material and restorative crown than the other models, due to its flexibility, the probability of debonding and crown failure in PEKK post-core system may be higher than that of rigid post-core systems.