Quantitative evaluation of the effect of different irrigation activation methods on the amount of irrigation solution overflowing from the apical in single root teeth with simulate open apex

The purpose of this study is to quantitatively compare the effect of SII, PUI, EA, EDDY methods used as the final irrigation activation method in root canal treatment on the amount of irrigation solution overflowing from the apical in single root teeth with an open apex. 60 teeth with single root and single canal were included in the current study. Root canals at the determined working lengths were prepared using the X1 (17.04), X2 (25.06), X3 (30.07) files of the ProTaper Next rotary file system. Dental tissues were removed with diamond discs from the marked reference points, and standardization was achieved in all teeth, with 5±1 mm crown and 11±1 mm root lengths. Peeso Reamer tips from #1 to #6 were used to simulate teeth with an open apex, and the apical diameter was standardized as 1.5mm. Root canals were irrigated with 2.5% NaOCl, 17% EDTA and distilled water. In the experimental setup, the teeth were fixed in the gaps opened on the caps of Eppendorf tubes. To prevent leakage, the gap between the cap of the Eppendorf tube and the tooth was sealed with cyanoacrylate. A 27 G needle was inserted into the cap as a drainage cannula with the tip at the root level. Eppendorf tubes were filled with NaOCl completely. To apply the final irrigation activation methods, after the preparation of the setups, the setups were randomly divided into four groups as SII, PUI, EA, EDDY (n=15). In all groups, 6 ml of 3% NaOCl was applied for 3 minutes in the final irrigation activation procedure. The extruded irrigation solution was collected from the drainage cannula with the help of an insulin injector, and the amount of increase was recorded in ml for each group. Kolmogorov-Smirnov test was used to evaluate the normality of the data, and the amount of extruded irrigant was analyzed statistically at the P<0.05 significance level using Kruskal-Wallis and Mann Whitney-U tests. While the highest mean irrigant extrusion was associated with the SII and PUI groups, less irrigation solution extrusion was observed in the EA group compared to the other groups. However, these are not statistically significant (P<0.05). Keywords: Immature apex, Final irrigation activation, Irrigation extrusion, SII, PUI, EA, EDDY