Effect of sonic and ultrasonic irrigation activation depth on apical debris extrusion: An In Vitro study

The aim of this study was to compare the effect of passive ultrasonic (PUI) and sonic (EDDY) activation systems at different depths on apical debris extrusion. All samples were randomly assigned to three groups based on the activation method to be used, and each group was further divided into two subgroups according to the activation depth (n=15): Group 1a: EDDY-1 mm, Group 1b: EDDY-2 mm, Group 2a: PUI-1 mm, Group 2b: PUI- 2 mm, Group 3a: Conventional -1 mm, Group 3b: Conventional-2 mm. Distilled water was used as the irrigation solution in all samples. Extruded debris and irrigation solution were collected in Eppendorf tubes, which were then incubated at 70°C for 5 days. The net debris weight was determined by weighing the tubes before and after the experiment using a precision balance. Normality was assessed using the Shapiro-Wilk test, and apical debris extrusion values were compared according to activation method and depth using two-way ANOVA, with multiple comparisons analyzed using Bonferroni post-hoc testing. A significance level of p<0.050 was set. The results indicated that EDDY caused significantly greater apical debris extrusion compared to PUI (p<0.001). Additionally, activation performed 1 mm from the apex resulted in significantly greater debris extrusion than activation performed 2 mm from the apex (p<0.001). However, no significant difference was found between depths within each activation method (p=0.768). PUI extruded less debris than EDDY for both penetration depths.