Comparative evaluation of penetration of root canal irrigant after using four different activation techniques under confocal laser scanning microscopy: An in vitro study

Aim: The aim of this study was to compare and evaluate the penetration depth of root canal irrigant after using Manual, EndoActivator, Ultra X, and Diode Laser-Assisted Irrigant activation technique. Materials and Methodology: Forty extracted single-rooted human mandibular premolars (N=40) were prepared using Neo Endo Flex Files up to size 25/6%, with saline irrigation during instrumentation. After chemomechanical preparation, canals were filled with Rhodamine B-labelled Twin Kleen dissolved in 10 mL of 3% sodium hypochlorite. Samples were randomly assigned to four groups (N=10) based on the activation technique: Group 1: Manual activation with a 25/6% Gutta Percha cone Group 2: Sonic activation using EndoActivator Group 3: Ultrasonic activation with Ultra X Group 4: Laser activation with a Diode Laser Transverse sections at 2, 5, and 8 mm from the apex were examined using confocal laser scanning microscopy to assess maximum irrigant penetration depth, which was statistically analyzed. Results: Laser activation achieved the greatest penetration in the coronal and apical thirds of root dentin, while Ultra X demonstrated superior penetration in the middle third. Conclusion: Diode laser-assisted irrigant activation showed greater penetration depth in the coronal and apical thirds of root dentin.