Effect of Different Irrigation Activation Techniques on Sealer Penetration: A Confocal Laser Microscopy Study.

Objective: To compare the efficiency of a new sonic powered irrigation system named EDDY (VDW, Munich, Germany), passive ultrasonic irrigation (PUI) and conventional needle irrigation (CNI) in root canal sealer penetration.

Methods: A total of 45 mandibular premolars were instrumented up to size 30, 0.9 taper and randomly divided into three groups (n = 15) depending on the final irrigation activation technique: EDDY, PUI or CNI. After the final irrigation procedures, the root canals were obturated with labelled sealer mixed with 0.1% rhodamine B. Transverse sections at 3, 5 and 7 mm from the root apex were examined using confocal laser scanning microscopy. The maximum depth and total area and percentage of sealer penetration were measured using ImageJ analysis software (National Institutes of Health, Bethesda, MD, USA).

Results: In the EDDY group, the penetration depth was higher compared to the CNI group in the apical and middle sections and compared to the PUI group in the apical section (P ˂ 0.05). The penetration area in the EDDY group was higher compared to the CNI group in all sections and compared to the PUI group in the coronal section (P ˂ 0.05). The percentage of penetration was higher in the EDDY group compared to the CNI group in all sections and compared to the PUI group in the coronal section (P ˂ 0.05).

Conclusion: In the present study, sealer penetration was superior in the EDDY group than the CNI group in the apical section. In the middle and coronal sections, sealer penetration was similar for the EDDY and PUI groups.