Dosing started within 6 hours after completion of third molar extraction. Study drug was given once every 6 hours for 12 hours (for a total of 2 doses). Participants were randomized to receive placebo or active drug (either experimental drug or comparator). The total dose was the same for both groups receiving active drug, but was given as either 1 dose of extended-release tablets (experimental drug), or 2 doses of immediate-release tablets (active comparator).