Aim: This study aimed to assess and compare the effect of two different post and core materials at two different post lengths on the fracture resistance of endodontically treated maxillary central incisors.
Materials and Methods: Twenty maxillary central incisors were selected, root canal treated and randomly divided into four groups (n=5/group): A.7mm glass fiber post and composite core. B. 10mm glass fiber post and composite core. C. 7mm PEEK post and core. D. 10mm PEEK post and core. After Post spaces preparation, fiber posts were bonded to the teeth followed by composite core build-up while, PEEK post/cores were CAD/CAM fabricated. Finally, lithium disilicate crowns were fabricated and bonded to all teeth.
Fracture resistance test was done using universal testing machine until failure occurred. Statistical analysis was performed using one-way ANOVA, and Tukey's post-hoc tests to detect significance between groups.
Results: Regarding post length, no statistically significant difference was found between groups (A), (B) of glass fiber post (P = 0.64) or between groups (C), (D) of PEEK post (P =0.95). While, significant difference between the two different materials of the same length was observed in (A) & (C) and (B) & (D) (P = 0.0001). Groups of glass fiber & composite core were had significantly higher fracture resistance than groups of PEEK post & core.
Conclusions: Glass fiber post and composite core exhibited higher fracture resistance compared with that made of PEEK material. Post length equal to clinical crown length provided high fracture resistance with less invasive post hole preparation.