Sasanakul P, et al. - In this study, 94 sterilized root samples with 0.8-mm wide apical foramen were studied to quantify the efficiency of disinfection methods and the most encouraging irrigation protocol for regenerative endodontics in teeth with large root canals. The samples were categorized into 9 groups viz, no intervention (initial), 1.5% NaOCl irrigation (1.5 N), 2.5% NaOCl irrigation (2.5 N), 1.5 N + intermittent passive ultrasonic irrigation (PUI), 1.5 N + intermittent canal brushing with Navitip FX (NFX), 1.5 N + intermittent XP-endo Finisher (XPF), 1.5 N + circumferential filing (CF), 1.5 N + 1-min Self-adjusting File (SAF), and 1.5 N + mechanical instrumentation using #90–110 files (MI). They recorded the lowest mean CFU count in the MI group (63.5 CFU/mL) and higher bacteria population in 1.5 N group. They concluded adjunctive NFX most effective in lessening the number of bacteria without removal of dentin.