Fracture Resistance of Endodontically Treated Premolar Teeth Restored with PEEK Post and Biological Dentin Post: An In Vitro Comparative Study

Purpose: To evaluate and compare the fracture resistance of endodontically treated premolar teeth restored with polyetheretherketone (PEEK) post and biological dentin post.Materials and methods: Twenty-eight freshly extracted single-rooted premolar teeth were selected.Specimens were divided into two groups.Group I included 14 teeth restored with computer-aided design-computer-aided manufacturing (CAD-CAM) fabricated PEEK posts, whereas group II included 14 teeth restored with biological dentin posts.Group I PEEK posts were milled from a 14 mm PEEK blank and were sandblasted.Group II posts were made by longitudinal sectioning of the teeth, followed by horizontal slicing above 2 mm occlusal to the buccal cementoenamel junction (CEJ) using a water-cooled air rotor.Post space was created in all endodontically treated teeth, and the posts were cemented using resin cement.All the teeth were subjected to a universal testing machine to evaluate fracture resistance.The difference between the fracture resistance of PEEK and biological dentin post was analyzed using an unpaired t-test.Results: Average fracture load of PEEK post was 1072.85 231.46 N, and for biological dentin post was 1352.71 145.69 N. Comparison between the fracture resistance of PEEK post and biological dentin post was observed to be statistically significant (p = 0.001).Mode of failure during fracture was found to be mixed, with the fracture line extending in the middle and apical roots, as well as vertical fracture of roots.Conclusion: Due to similar modulus of elasticity, endodontically treated teeth restored with PEEK post as well as dentin post show comparable fracture resistance.Within the limitations of the study, it can be concluded that posts made from biological dentin exhibit better fracture resistance, are economical, and can be used as an alternative to available commercial posts.