Evaluation of the efficacy of different irrigation systems on root canal filling material removal from curved canals using CBCT

The aim of this in vitro study; used in the final irrigation during retreatment; to compare the amount of gutta-percha and root canal sealer remaining on the canal wall to evaluate the effectiveness of needle irrigation, Irriflex irrigation, ultrasonic irrigation, and Eddy irrigation methods. In this study, 60 mandibular tooth canals is used with curvature of 200-400 according to the Scheneider method were used. After the shaping of the root canals was completed with ProTaper Next X2 (25/06), the canal filling was performed with the lateral compaction method using gutta-percha and AH Plus canal sealer. After the teeth were incubated at 37°C and humid area for 2 weeks, gutta-percha and root canal sealer were removed with ProTaper Universal Retreatment D1 (30/09), D2 (25.08), D3 (20.07) and ProTaper Next X3 (30/07). The teeth were randomly divided into 4 experimental (n = 15) groups and different final irrigation methods were applied: group 1 needle irrigation, group 2 Irriflex irrigation, group 3 ultrasonic irrigation, group 4 Eddy irrigation. CBCT images were taken after the teeth were embedded in wax and plaster. Canal volumes and residual canal filling volumes were calculated using the ImageJ program. The residual canal filling volume was calculated as a percentage of the residual canal filling volume by proportioning the canal volume. Obtained data were evaluated using One Sample Kolmogorov Smirnov statistical test and compared using One-way ANOVA statistical tests. There was no statistically significant difference between needle irrigation, Irriflex irrigation, ultrasonic irrigation and Eddy irrigation groups in terms of residual canal filling material amount in the root canal (p>0.05). None of the irrigation methods could completely remove the root canal filling and no statistically significant difference was found between the methods. Studies are needed to compare the effectiveness of Irriflex irrigation, ultrasonic irrigation and Eddy irrigation methods in the retreatment of curved root canals.