This study compares single-dose ibuprofen pretreatment for postoperative endodontic pain. Thirty-nine emergent patients were randomly assigned to 3 groups: placebo, ibuprofen tablets, or ibuprofen liquigels. Patients recorded their pain levels before and at the end of treatment, then every 6 hours for 24 hours after administration of the medications and standard endodontic treatment. Pain evaluations by using 3 pain scales (visual analog scale [VAS], category, and Heft-Parker) were highly correlated, suggesting the rationale for only using one pain scale in pain studies. No significant differences in postoperative pain levels were found between either single-dose ibuprofen formulation or the placebo control group (P = .84). Patients treated with calcium hydroxide versus obturation did not differ in postoperative pain levels (P = .44). This study suggests that single-dose pretreatment analgesia alone in endodontic pain patients will not significantly reduce postoperative pain below the reduction in pain from endodontic treatment.