Micro-CT Evaluation of the Remaining Endosequence BC Filling Materials and Dentinal Microcracks after Retreatment with D-Race and R-Endo Systems

Objective: To analyze the remaining EndoSequence BC filling materials and microcrack using micro-computed tomography after retreatment with D-Race and R-Endo systems. Methods: The canals of thirty mandibular single-rooted and single-canal premolar teeth were shaped and obturated with EndoSequence BC point and EndoSequence BC sealer. The samples were assigned into two groups and scanned with micro-computed tomography. Then, the canal filling materials were removed with D-Race and R-Endo systems. After all roots were re-scanned, all images were evaluated for the remaining EndoSequence BC filling materials and microcrack. Also, retreatment time was recorded. Results: The remaining filling material in the R-Endo group was greater than the D-Race group. Both systems caused new cracks formation. However, no significant difference was noticed among them. The D-Race group needed significantly less time in comparison to the R-Endo group. Conclusion: D-Race system was faster and more efficient compared with R-Endo system. D-Race and R-Endo files caused new cracks on the canal walls.