Group 4- XP-endo Finisher: Irrigation protocol was same as Group 3 with the exception that the XP-endo Finisher (FKG, Dentaire Sa, La Chaux-de- Fonds, Switzerland) was used instead of the CanalBrush at 800 rpm with 1 Ncm for 1 min. The file tip was placed 1 mm short of the WL.