Examination of removability of bioceramic-based canal sealers from canal walls during retreatment

The aim of this in vitro study was to compare of removability of EndoSeal MTA and Well Root ST, which are current bioceramic-based canal sealers, in comparasion with AH Plus, a resin-based root canal sealer, from canal walls during retreatment. For this purpose, 36 oval canal mandibular premolar teeth were used. The canals were shaped to apical size # 40 using the Protaper Next rotary instrument system. Samples were filled by lateral condensation method using Well-Root ST, EndoSeal MTA and AH Plus Jet root canal sealers (n = 12). Root canal filling removal was performed using ProTaper Universal Retreatment files. Samples were divided into two equal part as buccolingual. In order to evaluate the amount of filling material remaining on the canal walls, the images taken from apical, middle and coronal part with x8 magnification stereomicroscope were analyzed with Adobe Photoshop 2020. One-way ANOVA and post-hoc Bonferroni tests were used for statistical analysis. EndoSeal MTA, which has the shortest time to reach working length, is removed in a shorter time compared to Well-Root ST (p <0.001) and is similar to AH Plus Jet (p> 0.05). When the remaining filling materials amount is evaluated as apical, middle, coronal and whole root canal, there is no statistically significant difference between the three sealer (p> 0.05). While the amount of debris in the root canal wall is the highest in the Well- Root ST group in the coronal part (p <0.001), there is no difference between the groups in the apical and middle part (p> 0.05). While the amount of smear layer is highest in the Well- Root ST group in the middle and coronal part (p <0.001), there is no difference between the groups in the apical part (p> 0.05). The highest amount of debris and smear layer in the whole root canal was found in Well-Root ST group (p <0.001). According to the results of this study, obturation material could not be completely removed in any group. Additional techniques and equipment are needed to improve cleaning of the root canal during retreatment.