Evaluation of calcium hydroxide removal using EndoActivator system: An in vitro study

Aim: The aim of this study was to compare the calcium hydroxide (Ca(OH) 2 ) removal efficacy of the EndoActivator system with that of conventional irrigation with a syringe and hand file manipulation. Materials and Methods: A total of 44 extracted human single-rooted mandibular premolars were used. The root canal systems of all teeth were cleaned and shaped, then filled with Ca(OH) 2 paste. The teeth were divided into two groups: Ca(OH) 2 was removed using ethylenediaminetetraacetic acid (EDTA) and sodium hypochlorite (NaOCl) with hand filing and irrigation (Group 1) or the EndoActivator system (Group 2). Each tooth was split into two halves and examined under a scanning electron microscope. Results: Ca(OH) 2 particles were completely removed at the coronal level in both experimental groups. More Ca(OH) 2 particles were present in the apical third than in the middle-third in both groups. No significant interaction was observed between the two experimental groups or among the three examined levels (P > 0.05). Conclusion: Agitation with NaOCl and EDTA improved Ca(OH) 2 removal only in the coronal third of the root canal. Use of the EndoActivator system did not improve the efficacy of Ca(OH) 2 removal in the middle and apical thirds