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.~Before root canal treatment, eligible participants will be randomly assigned to one of the following groups: experimental group (taking 600 mg of clindamycin orally) or control group (taking placebo ) 30 minutes before the start of the treatment. Single-visit root canal treatment will be performed.~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
The aim of this prospective, randomized, placebo controlled study is to evaluate the effect of clindamycin on post-operative pain and swelling in adult patient with symptomatic apical periodontitis.