Efficacy of Different Irrigation Systems Used to Remove Calcium Hydroxide from the Root Canal

Introduction: The present study aimed to compare the cleaning efficacy of passive ultrasonic irrigation (PUI), selfadjusting file (SAF), EndoVac, and conventional syringe irrigation (CSI) techniques on Ca(OH)2 removal from the root canal. Methods: This study was conducted on the mesial roots of 36 human mandibular molar teeth. After 1 month, the Ca(OH)2 was removed from the experimental groups using four different irrigation techniques (SAF, PUI, EndoVac, and CSI). The inner surfaces of the canals were examined using a stereomicroscope at 30x magnification. The assessment of remaining Ca(OH)2 medicament in the grooves was performed by three calibrated dentists using a scoring system ranged 03. Results: None of the groups showed complete Ca(OH)2 removal from the root canals. The PUI technique removed significantly more Ca(OH)2  from all root canals, compared to EndoVac and CSI techniques  (P lt;0.05). In the apical third, SAF group results were significantly better than the CSI group results (P lt;0.05). In the middle third, the SAF technique led to significantly better results in the removal of Ca(OH)2, compared to  the techniques used in other groups (P lt;0.05).Conclusion: Currently, there is no irrigation system that can completely remove Ca(OH)2 from the root canal in endodontics. Regarding the removal of Ca(OH)2 from root canals, the PUI technique was significantly better than EndoVac and CSI techniques. In addition, the SAF technique showed significant efficacy in the middle third of the root canals.