Abstract: [Abstract] Objective： To evaluate the outcome of single-visit and two-visit root canal treatment in patients with chronic apical periodontitis with iRoot SP sealer after a 1-year follow up period. Methods： Three hundreds maxillary and mandibular teeth with chronic apical periodontitis were randomly assigned into two groups. While the teeth of patients in treatment group were obturated, control group were temporarily sealed and obturated after one week. All canals were filled with iRoot SP sealer. The healing results were clinically and radiographically evaluated 1 years postoperatively. Results： Of the 300 teeth treated, 134 teeth (91.16%) in treatment group were healed compared with 137 teeth (92.57%) in control group, 8 cases (5.44%) in treatment group were classified as uncertain compared with 6 cases (4.05%) in control group, 5 cases(3.40%)in the treatment group and 5 cases(3.38%) in the control group were classified as not healed. Chi-square test was used to compare the success rate of the two groups. Statistical analysis of the healing results did not show any significant difference between the groups (P>0.05). Conclusions： There was no statistically significant difference between the single-visit and two-visit root canal treatment in patients with chronic apical periodontits filled by iRoot SP sealer.

Key words: iRoot SP sealer, chronic apical periodontitis, root canal treatment