Abstract: Objective To compare the effects of iRoot SP single-cone filling method and AH Plus warm vertical condensation technique on postoperative pain levels in patients undergoing root canal treatment. Methods A total of 200 patients who underwent root canal treatment from October 2022 to October 2024 were enrolled and divided into an observation group （n=100, iRoot SP single-cone filling technique） and a control group （n=100, AH Plus warm vertical condensation technique） according to the different obturation methods. The pain levels at various stages after treatment and the treatment outcomes at three months postoperatively were compared between the two groups. Results Before the surgery, there was no statistically significant difference in the numerical rating scale （NRS） pain scores between the two groups of patients （P>0.05）. On days 1, 3, 5, and 7 postoperatively, the NRS scores in the observation group were significantly lower than those in the control group （P<0.05）. The treatment effectiveness rate in the observation group was 98%, which was higher than 90% in the control group （χ²=4.344, P<0.05）. Conclusion The use of iRoot SP single-cone filling method in root canal treatment can reduce postoperative pain levels in patients and result in better treatment outcomes 3 months postoperatively compared to the traditional AH Plus warm vertical condensation technique.

Key words: iRoot SP single-cone filling method, AH Plus warm vertical condensation technique, Postoperative pain, Root canal treatment