Comparision of Pain Scale after Single-Visit Root Canal Treatments by Different Temperatures and Concentrations of NaOCl in Mandibular Molars with Irreversible Pulpitis

Abstract

Background & aim; Aim Sodium hypochlorite is used as a gold standard for root canal irrigation, however, there is no consensus about its best concentrations and temperature. This study assessed the pain scores after single-visit root canal treatments using sodium hypochlorite irrigant with different concentrations and temperatures in the mandibular molars with irreversible pulpitis. Materials & Methods In this randomized, controlled clinical trial, 72 patients with mandibular molars having irreversible pulpitis were randomly assigned to 6 groups. The teeth were anesthetized using the inferior alveolar block method, and manual K-files and Denco rotary files were used to prepare the root canals. During the instrumentation, the root canals were irrigated by NaOCl solution at concentrations of 0.5% and 1.0% and tempratures of 2.5°C, 22°C and 40°C. Cryotherapy was used to create a temperature of 2.5°C. The root canals were dried with paper points and obturated with gutta- percha and AH26 sealer using the cold lateral compaction technique. The patients recorded their pain intensity at different time intervals based on the visual analogue scale (VAS) and reported the number of analgesics they used. Patients pain after taking painkillers was classified into 4 groups. VAS pain scores were compared with repeated-measures ANOVA. Kruskall-waliis test was used to compare groups regarding pain at each time interval; the Friedman test was used to compare the groups at different time intervals. Results Changes in VAS pain scores of all the groups were significant over time (p<0.001). Pain in all the groups decreased immediately after treatment and increased three hours after treatment. The difference in mean pain between the groups was not significant. There was no significant differences between the mean pain scores of patients in different groups and their analgesics at each time interval. There were no significant difference in pain ratings and the number of analgesics used in the groups of NaOCl with different concentrations and temperatures over time. Conclusion Differen concentrations and temperatures of NaOCl irrigation have no significant effect on pain intensity following endodontic treatment of mandibular molars with irreversible pulpitis.