Cleaning protocols to enhance bond strength of fiberglass posts on root canals filled with bioceramic sealer: an in vitro comparative study.

Objectives: This study aimed to evaluate whether the agitation protocols using ultrasonic inserts or the XP-endo Finisher R file improved the removal of two different endodontic sealer remnants and the bond strength of fiberglass posts to dentin.

Methods: Seventy-two human teeth were selected. The canals were prepared with Reciproc 50 and Easy ProDesign 30/.10 and root filled according to the endodontic sealer groups: AH Plus or EndoSequence BC Sealer HiFlow. The samples were kept at 37ºC and 95% humidity for 28 days. During the post space preparation, the obturation was removed with Largo burs, and the groups were divided according to the irrigant agitation protocols (n = 12): no agitation, agitation with R1-Clearsonic associated with E1-Irrisonic ultrasonic inserts, or agitation with XP-endo Finisher R file. The fiberglass posts were cemented with RelyX ARC. The roots were sectioned into slices and submitted to the push-out test. Micro-computed tomography analysis was used to check the effectiveness of irrigating solution agitation in the elimination of remnants.

Results: The cleaning protocols with agitation were more effective in increasing the bond strength of posts to dentin for both sealer groups compared to non-agitation (p < 0.05). There was no difference between the same cleaning protocols for the different sealers. Among the different thirds, there was no statistical difference for the same sealer in the different cleaning protocols (p > 0.05).

Conclusions: Both agitation protocols effectively clean root-filled canals sealed with resin-based and calcium silicate-based sealers during fiberglass post space preparation. These protocols result in improved bond strength compared to non-agitation methods.