RESUMO
Background: To evaluate the effect of surface treatments on adhesion of milled PEEK post to two different composite resin core-build up materials. Material and Methods: Six PEEK posts were divided into the following groups: G1: no treatment+ Grandio core material, G2: no treatment+ Bulk-fill core material, G3: 98% sulfuric acid for 60 seconds+ Grandio core material, G4: 98% sulfuric acid for 60 seconds+ Bulk-fill core material, G5: 50 µm airborne particle abraded + Grandio core material, G6: 50 µm airborne particle abraded + bulk fill core material. The adhesion of the post to core build-up materials was tested using micro push-out bond strength. Data were analyzed using ANOVA and Tukey's test. Results: There was a significant effect for the surface treatment (p<.001), a non-significant effect for the core build-up materials (p<.289), and a significant effect for their interaction (p<.001) on the bond strength values. Conclusions: Within the limitation of this study, sulfuric acid etching group significantly increased the bond strength compared to other groups. Bulk-fill core material could be a feasible option when restoring ETT in terms of saving chair time and the treatment procedure simplicity. Key words:Bond Strength, Core material, PEEK, Surface Treatment.