The additive effect of clonidine to lidocaine on postoperative pain management after root canal treatment on mandibular molars with symptomatic irreversible pulpitis: A prospective randomised double-blind clinical trial

CONTEXT: Postoperative pain control has been a common challenge to clinicians in endodontics. AIMS: This double-blind randomized clinical trial assessed the efficacy of clonidine added to lidocaine for postoperative pain following endodontic treatment of mandibular molars with symptomatic irreversible pulpitis (SIP). METHODS: One hundred participants with lower molars experiencing SIP were recruited and randomly assigned to two groups. 1.8 mL of 2% lidocaine with either epinephrine (1:80,000) or clonidine (15 µg/mL) was administered to each group via an inferior alveolar nerve block. A Heft–Parker Visual Analog Scale was used to rate preoperative pain and at 6, 12, 24, 36, 48, and 72 h following endodontic treatment. Their postoperative analgesic consumption was recorded. STATISTICAL ANALYSIS USED: The analgesic efficacy was analyzed by Chi-square test, paired t-test, and repeated measures ANOVA (P < 0.05). RESULTS: Early postoperative pain was significantly lower in the lidocaine/clonidine group than the lidocaine/epinephrine group (6 h: P = 0.038; 12 h: P = 0.031). The lidocaine/clonidine group consumed a significantly lower amount of analgesics (P = 0.048). CONCLUSIONS: The administration of clonidine added to lidocaine may reduce early postoperative pain and consumption of analgesics following endodontic treatment in lower molars with SIP.