The influence of different treatments on fiber post and root canal to bond strength of fiber post

Different methods were used to treat the fiber posts and root canals, and evaluated their influence on the bond strength of fiber posts. After thirty extracted human, single-rooted premolars were endodontically treated and post space was prepared in each tooth with post drills, they were randomly assigned into nine groups with 33 fiber glass posts. Different treatment methods for fiber posts and root canals were applied. Following post cementation, slice specimens were prepared. The push-out test was performed using a universal testing machine, and the failure modes were examined with a stereomicroscope. Bond strengths (mean ± SD) were: CC group (7.07 ± 1.51 MPa); CE group (10.57 ± 2.90 MPa); CM group (10.06 ± 3.00 MPa); SiC group (7.23 ± 2.06 MPa); SiE group (10.51 ± 2.26 MPa); SiM group (10.50 ± 2.70 MPa); PC group (9.79 ± 2.79 MPa); PE group (11.70 ± 1.76 MPa); PM group (11.06 ± 3.17 MPa). The bond strength of polydopamine group was significantly higher than silane group and control group (p < 0.05). NaClO/EDTA group had higher bond strength than the MTAD group, and both were higher than the control group (p < 0.05). Combined treatment of fiber post and root canal was more advantageous to improve the bond strength between fiber post and root canal. Surface polydopamine functionalization was confirmed to be a reliable method for improving the bond strength of fiber posts. The effect of 5.25% NaClO + 17% EDTA solution on the bond strength is more significant than MTAD solution. When the fiber posts were treated with PDA and the root canals were treated with NaClO/EDTA, the best bond strength can be obtained. In this experiment, fiber posts and root canals were treated separately. The aim of this paper is to explore the influence of different treatment methods on the bond strength of fiber posts, in order to screen out the most effective processing methods and provide theoretical guidance for the clinical application.