Evaluation of mechanical properties of different polyetheretherketone endodontic post systems: an in vitro study

Abstract

Background Survival of endodontically treated teeth depends on an efficient restoration of the missing tooth structure. Objectives This study aimed to investigate the mechanical properties of different endodontic post systems. Materials and methods Human permanent maxillary central incisors (no.=58) were decoronated and root-filled. The specimens with prepared root canals were randomly divided into Group P: Polyether Ether Ketone (PEEK) post and composite core and Group C: custom-made post-core of PEEK. The cementation of the posts was carried out using self-adhesive resin cement. Nano-hybrid composite resin was used for core fabrication. After cementation, the specimens from each group were randomly divided into two subgroups according to the types of tests utilized: 14 from each group were for the fracture strength test, which was restored with IPS e-max CAD crown, and 15 from each group for the pullout resistance test. A universal testing machine was used for the test performance. Results The fracture resistance test showed that the values significantly differed among tested posts (P = 0.013). Group P showed the highest fracture resistance. Group C exhibited higher mean pullout resistance values than the other group (P) (P = 0.059). In the two-piece PEEK post and composite core, the predominant type of failure was a core fracture, while in the one-piece PEEK post-core, most types of failures were either in the crown or in the post. Conclusions The prefabricated posts are more resistant to fracture than the custom-made posts, with fracture and displacement mainly of the core. In contrast, both showed similar pullout resistance.

Effect of Ferrule Design on Stress Distribution of Maxillary Incisor Rehabilitated with Ceramic Crown and PEEK Post–Core Material: A 3D Finite Element Analysis

“…Core-posts made of PEEK were also tested in vitro in recent studies [39,40]. Sugano et al [40] prepared experimental specimens using extracted bovine mandibular incisors without ferrule.…”

“…Based on the maximum load to fracture, the researchers concluded that glass fiber post, glass fiber post in glass fiber sleeve, and PEEK post in glass fiber sleeve showed a higher fracture load when compared with other groups and therefore were recommended in cases with flared root canals. Ahmad et al [39] carried out similar tests using 58 human permanent maxillary central incisors divided into two groups: prefabricated PEEK post plus composite core and PEEK custom-made post-core. The specimens were submitted to a pullout resistance test or fracture strength test after restoration with IPS e-max CAD crown.…”

Evaluation of Poly(etheretherketone) Post’s Mechanical Strength in Comparison with Three Metal-Free Biomaterials: An In Vitro Study

“…Moreover, our protocol slightly differs with those retrieved in previous publications, as we chose to perform a tissue preparation before sealing the posts in order to create a ferule effect on the tooth. This parameter was also designed in only 5 publications of the 22 published since 2020 [53,55,[57][58][59]. It may also be worth highlighting one of the parameters that varies greatly between the different studies, namely the type of support on which the tests have been carried out.…”

“…It may also be worth highlighting one of the parameters that varies greatly between the different studies, namely the type of support on which the tests have been carried out. Without taking into account numerical simulation analyses, in vitro tests have been carried out on natural human teeth [56,59,60], bovine teeth [55,57,61] or artificial supports [62,63], which can significantly change the results obtained. Finally, the last parameters that may influence the differences observed between the studies concern the nature of the assembling biomaterial or the post's size.…”