Effect of root-end resection and root-end filling on apical leakage in the presence of core-carrier root canal obturation.

Aim: To evaluate the apical seal of canals filled with a core-carrier obturator following root-end resection with and without a root-end filling. Methodology: Thirty single-rooted human teeth with single canals were used. Root canal treatment was performed and canals filled with a core-carrier obturation technique. The teeth were then randomly assigned to three groups (n ¼ 10). In the first group root canal filling only was performed. After orthograde filling, the teeth of the second group were resected apically, perpendicular to the major axis of the root. In the third group after apical resection, a root-end cavity was prepared using ultrasonic diamond retrotips and the cavities filled with Super-EBA cement. During a period of 3 h and with a headspace pressure of 0.12 atm, methylene-blue solution was forced through a tube that was connected to the apical end of each tooth specimen. The coronal end of the tooth was connected to a capillary tube containing an air bubble. Leakage was evaluated by observing the distal displacement of the air bubble. The roots were then sectioned along their long axis. Using a stereomicroscope, linear dye infiltration at the dentine–cement interface was determined. Kruskal–Wallis and Mann–Whitney tests were used to compare the three groups. Results: Linear dye infiltration was significantly greater in root canals filled with the core-carrier obturators and resected apically (0.9 ± 0.9 mm) when compared with those that had root-end fillings (0.2 ± 0.4 mm). Air bubble displacement was not observed. Conclusion: Root-end filling improves the sealing of roots with core-carrier obturation following root-end resection.