Evaluation of the effectiveness of different irrigation activation techniques in removing bioceramic based sealers from root canals

Introduction: Retreatment is one of the treatment options in cases where primary root canal treatment fail. Failure to completely remove the previous root canal filling material may negatively affect the success of the treatment. Aim: The aim of this study is to compare the effectiveness of conventional needle irrigation, Ultra- X and EDDY final irrigation activation methods with scanning electron microscope after retreatment of root canal fillings using Bioserra and MTA Fillapex root canal sealers. Material-Method: 108 extracted single-rooted human teeth were prepared with ProTaper Next X1 (17.04) and X2 (25.06) rotary files. The samples were randomly divided into two main groups (n =54) according to the sealers used. Group 1: MTA Fillapex, Group 2: BioSerra. The samples were kept for 2 weeks after filling with gutta-percha and root canal sealer. The canal fillings were removed using ProTaper Next X2 (25.06) and X3 (30.07) rotary files and AI endodontic motor. According to the final irrigation procedures, the teeth were divided into 6 groups (n = 18). Group 1, MTA Fillapex- Conventional needle irrigation (CNI), Group 2, BioSerra-GII, Group 3, MTA Fillapex- EDDY, Group 4, Bioserra- EDDY, Group 5, MTA Fillapex- Ultra X, Group 6, Bioserra-Ultra X. After final irrigation procedures, the roots were divided into two parts in the buccolingual direction and examined under a scanning electron microscope. The presence of residual root canal filling material was scored in 5 steps, including the apical, middle and coronal third regions. The data were statistically analyzed. Results: All groups had retaineal material in the root canals. While EDDY activation technique was more effective in removing MTA Fillapex root canal sealer (p<0,001), Ultra- X was found to be more effective in removing Bioserra root canal sealer (p=0,003 ve p<0,001). Among the Ultra- X activation groups, Bioserra root canal sealer were found to be higher than MTA Fillapex in the middle and apical third regions (p<0,001). As a result of the activation of MTA Fillapex with Ultra- X, apical section were found more retaineal material than in the coronal and mid-section (p<0,001), while in the mid-section were found less retaineal material compared to the coronal as a result of the activation of Bioserra with Ultra- X (p=0,002). Conclusion: According to the results of the study, EDDY may be preferred to Ultra- X and Gİİ in removing MTA Fillapex root canal sealer. Ultra- X may be preferred over other activation techniques in removing Bioserra root canal sealer.