MK-0703 is a selective cyclooxygenase-2 inhibitor investigated for the treatment of acute pain and inflammation. The purpose of this single-dose, randomized, double-blind, double-dummy, placebo-controlled, parallel-group study was to compare MK-0703 12.5, 50, and 100 mg with ibuprofen 400 mg or placebo in patients who experienced moderate to severe pain after surgical removal of at least 2 third molars. Overall analgesic effect, duration of analgesic effect, time to onset of analgesic effect, peak analgesic effect, and tolerability were assessed over a 24-hour postdose period. The primary endpoint of this study was total pain relief over 8 hours postdose. The study included 121 patients (mean age, 23 yr); 16, 31, 28, 31, and 15 patients enrolled in the placebo, MK-0703 12.5 mg, MK-0703 50 mg, MK-0703 100 mg, and ibuprofen 400 mg groups, respectively. Both MK-0703 50 and 100 mg were significantly more effective than placebo for all endpoints (P < 0.01) and comparable with ibuprofen 400 mg. The onset of analgesic effect in the MK-0703 50 mg and 100 mg and ibuprofen 400 mg groups did not differ significantly from each other (P > 0.20). MK-0703 was generally well tolerated in single doses up to 100 mg. In summary, MK-0703 50 and 100 mg were efficacious in the treatment of postoperative dental pain and were indistinguishable from the active comparator, ibuprofen 400 mg.