The HyFlex EDM GPF (size 10/0.05) was operated with an endomotor (X-SMART, Dent- sply Maillefer, Switzerland) in continuous rotation at a speed of 300 rpm and 1.8 N·cm of torque, according to the manufacturer's instructions. Irrigation with 5.25% NaOCl and 17% EDTA was carried out...