Displacement of Apical Plugs Fabricated from Calcium Hydroxide Paste in Three Root Canal Filling Techniques

Objective: The present study evaluated the displacement of calcium hydroxide apical plugs in the root canals of teeth with enlarged apical foramens subjected to three filling techniques: lateral condensation, a hybrid method, and a thermoplastic technique (Ultrafil). Methods: The root canals of 30 extracted single-rooted human teeth were drilled in reverse order with no. 1-5 Gates-Glidden drills using a crown-down technique until the no. 1 drill passed through the apical foramen. The specimens were prepared with K files, beginning with a 50 K file and progressing until a 90 K file was visible 1 mm beyond the apex. Apical plugs were fabricated from calcium hydroxide paste, and the specimens were stored at 37°C at 100% humidity for 3 days. They were allocated into three experimental groups (n=10) according to the root canal technique. After filling, the specimens were incubated for 48 h at 37°C and longitudinally sectioned to assess apical plug displacement. Data was analysed by Kruskall-Wallis and Dun´s tests. Results: The hybrid method caused the largest average apical plug displacement (1.96 mm), followed by the lateral condensation technique (0.85 mm) and the Ultrafil system (0.59 mm). Conclusions: According to the results obtained in this study, when a 5mm apical plug is fabricated using L & C paste, filling of the remaining root canal can be performed with lateral condensation technique, hybrid method or Ultrafill.