Effect of Amoxicillin/Clavulanic Acid Combination on Postoperative Endodontic Pain

Medical and dental history will be obtained from all patients participating in this trial. Clinical and radiographic evaluation for each tooth included in this study will be recorded. Clinical diagnosis of symptomatic apical periodontitis is to be confirmed. After single-visit root canal treatment, eligible participants will be randomly assigned to one of the following groups: experimental group (taking oral tablet 1000 mg of Amoxicillin/ clavulanic acid combination) or control group (taking placebo tablet). Each patient will receive a 7-day diary to record postoperative pain and swelling.In case of pain, the participant will be instructed to take an analgesic. Post-operative pain will be measured as a primary outcome on 11-point scale (NRS) at the following time points: 6, 12, 24, 48, 72 hours and 7 days. The occurrence of swelling will be reported by participant as a secondary outcome.