RESUMEN
Aim: To evaluate the efficacy of various irrigating solutions on calcium hydroxide (Apex cal andRC cal) removal with the use of ultrasonics. Methods: The root canals of 120 single-rootedmaxillary central incisors were prepared using the stepback technique. The teeth were decoronatedand split longitudinally. After filling, the two halves of roots were reassembled with sticky wax andeach group was further divided into four subgroups according to the irrigating solution: SmearClear, 10% citric acid, 5% EDTA and 3% NaOCl. Evaluation for cleanliness was done under amicroscope with ×12.5 magnification. Statistical analysis was done with Kruskal Wallis and MannWhitney tests at 5% level of significance. Results: There was no statistically significant difference(p>0.05) for calcium hydroxide (Apex Cal and RC Cal) removal by different irrigants. There weremore residues in the apical groove than in the coronal groove (p<0.05). Conclusions: Whenthe different irrigants were compared at coronal and apical levels, Smear Clear and citric acidwere more effective in calcium hydroxide removal than EDTA and NaOCl.