Antimicrobial Impact of Various RC Final Irrigation Activation Techniques

5 mL of 2.5% NaOCl solution will be activated with a well-fitting gutta-percha cone that will be placed to full working length and then will be moved in push-pull strokes of 2 mm amplitude at a frequency of 100 strokes in about 1 min

5 mL of 5.25% NaOCl solution will be activated with PUI using a #20 endosonic file that will be driven by an ultrasonic device on medium power setting for 1 minute and inserted 1 mm short of the working length

5 mL of 5.25% NaOCl solution will be activated with XP-Endo Finisher which will be used in the canal for 1 minute at 800 rpm and 1 Ncm up to the working length and in slow up-and-down movements at 7-8mm length according to the manufacturer's recommendations

First, root canals will be filled with 0.5 mL of 0.05% ICG dye and left in place for 1 minute as preirradiation time. A #20 laser fiber will be inserted into the root canals to the working length. Then infrared diode laser with a wave length of 810 nm will be used to activate the dye for 30 seconds. For activation, circular movements will be performed along with the fiber removal movement . After the first activation, dye will be reintroduced, the laser fiber will be inserted again, and a new activation cycle of 30 seconds will be performed similarly to the previous one