[Bond strength of different resin composites to fiber-reinforced posts]

Endodontically treated teeth often have little coronal tooth tissue remaining and as such require a post to retain the core and the restoration. Therefore, tooth coloured adhesive inserted fiber posts in combination with resin based core material can be used. In this study, the tensile bond strength of core materials to fiber posts was investigated. Three different core materials, Clearfil Core, CoreRestore 2 and MultiCore Flow in combination with two different fiber posts systems, ER DentinPost and DT Light Post, were tested. The posts were shortened to the lengths of 15 mm. The specimens were obtained while the upper part (3 mm) of the posts was covered with standardized cylinders of the core materials. Clearfil Core in combination with the DT Light Post (230.5 N +/- 42.2 N) and ER DentinPost (154. N +/- 33.6 N) had the highest tensile bond strengths of all groups. The tensile bond strength of CoreRestore 2 to DT Light Post (149.9 N +/- 29.5 N) was higher than the tensile bond strengths of the combinations MultiCore Flow/DT Light Post (140.9 N +/- 31.4 N) and Multi- Core Flow/ER DentinPost (122,. N +/-19,. N). The group Core-Restore 2TER DentinPost had the lowest tensile bond strengths (80,1 N ++/-19,4 N). The adhesion of the resin based core materials to the fiber posts is influenced by the post design and core materials. The combination of core materials with the type of fiber post has a great influence on the tensile bond strength.