Abstract Objective：To explore the influence of ultrasonic irrigation of pain after root canal treatment.Method： A retrospective analysis was performed on 189 cases of root canal therapy in our hospital from December 2013 to December 2014，and were divided into control group（ 94 cases） and observation group（ 95 cases） according to cleaning method after root canal preparation，and were given conventional syringe irrigation and ultrasonic irrigation. Pain scores after operation of the two groups were observed and compared.Result：The postoperative pain score of the observation group through statistical and comparative was significantly lower than the control group（ P<0.05）.Conclusion：The acceptance of root canal therapy patients after root canal preparation ultrasonic irrigation can significantly reduce the postoperative pain degree.
