Patients with moderate-to-severe preoperative pain are selected. Patients receive either a single-dose of diclofenac potassium (50mg)- acetaminophen (1000mg) combination, diclofenac potassium (50mg) alone or a placebo tablet as a control. All patients will receive the assigned premedication one hour before single-visit root canal treatment. Anesthetic success of inferior alveolar nerve block will be assessed during access and instrumentation. Postoperative endodontic pain is measured at the following time points: 6,12,24,48,72h and 7 days after treatment.
The purpose of this study is to assess the effect of preoperative a single-dose of 50 mg diclofenac potassium- 1000mg acetaminophen combination compared to diclofenac potassium alone or placebo on local anesthetic success and postoperative pain in patients with symptomatic irreversible pulpitis.