INTRODUCTION: In this study, the ability to remove obturation material in canals filled with Bio C Sealer, BC Sealer Hiflow and AH Plus was compared using micro-computed tomography (micro-CT). MATERIALS AND METHODS: In phase 1, forty-five premolars were prepared with Reciproc Blue 25 files and divided into three experimental groups according to sealer and obturation technique (n=15): Group HI - BC Sealer Hiflow and continuous wave technique
Group AH - AH Plus and continuous wave technique
Group BC - Bio C Sealer and single cone technique. The teeth were stored for 30 days and scanned by micro-CT to evaluate the volume of the obturation material. In phase 2, the teeth were unblocked with the Reciproc R40 file and the Flatsonic ultrasonic insert and scanned again. In phase 3, all samples were subjected to passive ultrasonic irrigation (PUI) and a final scan was performed. The volume of obturation material was compared across all phases and groups. The volume of obturation material was calculated for the entire canal using an ANOVA analysis with a significance level of 5%. RESULTS: The BC group showed a significant difference compared to the AH group (p=0.005) and HI group (p<
0.001). There was no significant difference between the AH and HI groups. Within the groups, only the comparison of phase 2-3 in the HI group showed no significant difference (p=0.005). No group achieved complete removal of the obturation material. CONCLUSION: Bio C Sealer had the least residual obturation material and PUI improved material removal in AH Plus and Bio C Sealer sealers, but not in BC Sealer Hiflow sealer.