Rodig T, et al. - Using micro-computed tomographic (micro-CT) analysis, authors examined the ability of sonically and ultrasonically activated irrigation on the removal of accumulated hard-tissue debris (AHTD) in mesial root canal systems of mandibular molars. They assigned 10 roots to 4 different final irrigation groups ie, sonically activated irrigation with EndoActivator (EA) or EDDY (ED), ultrasonically activated irrigation (UAI), and manual irrigation without activation (MI). They performed final irrigation procedures using a total of 5 mL 1% NaOCl and 5 mL 15% EDTA per canal over a time of 5 min with an activation time of 4 x 20 s. They observed the inadequate removal of AHTD from mesial root canals systems in none of the final irrigation protocols.