ABSTRACT
Aim: To compare and evaluate the efficacy of different irrigation techniques in removing calcium hydroxide from apical third of root canal. Materials and methods: Root canals of forty five single rooted mandibular premolars were prepared using rotary ProTaper upto F3. The roots were split longitudinally and a groove made in apical third and filled with calcium hydroxide powder mixed with distilled water. The two halves were reassembled and irrigation was done as per the study protocol. The specimen were disassembled and examined under stereomicroscope for the amount of remaining calcium hydroxide in the groove. Result: No significant difference was found between passive ultrasonic irrigation (Endosonic PS tips) and Laser Activated irrigation (Er,Cr:YSGG Laser)in removing calcium hydroxide from root canals but significant difference was found when compared to needle irrigation. Conclusion: Endosonic PS tips and LAI was superior in removal of calcium hydroxide from root canals as compared to needle irrigation though none of them could completely remove the medicament