Effect of customisation, root canal reshaping and acid etching on push-out bond strength of fiber post in flared, MTA repaired root canal.

BACKGROUND: Clinicians routinely encounter the endodontically treated teeth with wide flared canals and mineral trioxide aggregate (MTA) repair on the canal wall. OBJECTIVE: To assess the effect of customized glass reinforced composite (FRC) post and reshaped root canal along with different acid etching protocol of MTA surface on push-out bond strength (PBS) in flared, MTA repaired root canal. METHODS: Ninety recently extracted single-rooted premolar teeth were sequentially subjected to root canal obturation, post space preparation, flaring, and MTA application. The samples were randomly divided into 3 groups of control (no relining or reshaping), customized FRC post by relining with self-adhesive resin cement and reshaping the canal with flowable composite. Each group was subdivided into 3 subgroups (n= 10) as no surface treatment, 37% H3PO4 and 19% EDTA etching of MTA surface. Teeth samples cemented with FRC post were sectioned into 2 mm and push-out testing. RESULTS: Control group had the lowest PBS at 1.988 N. The PBS values for the groups with customized post relining were 8.489 N, 8.888 N and 7.911 N for control, H3PO4 etch and EDTA etch. The corresponding PBS values for root canal reshaping were 7.323 N, 8.318 N and 7.785 N. CONCLUSIONS: Customized FRC post with 37% H3PO4 etching is advised for the flared and MTA repaired root canals.