• Time at which the proportion of subjects indicating non-zero pain relief for each active treatment becomes statistically significantly superior to placebo.
  

• Pain intensity differences from baseline and pain relief at each measurement time; Area under the curve of pain relief scores at 1 hour (TOTPAR1); Pain intensity differences at 1 hour (SPID1); Subject's global assessment of pain relief at one hour
  

The primary objective of this randomized, double-blind, placebo-controlled study is to determine the onset of analgesia following the administration of a single dose of 1000 mg of acetaminophen, 400 mg of ibuprofen or placebo in subjects experiencing acute postoperative dental pain secondary to the surgical extraction of at least three molars, with at least one being a partial or complete bony mandibular third molar impaction. After reporting moderate to severe pain following dental surgery, subjects record their baseline pain intensity and are treated with a single oral dose of acetaminophen, ibuprofen, or placebo. Subjects evaluate their pain intensity and pain relief relative to baseline at various timepoints up to 4 hours taking study medication. Pain intensity is assessed using a five-point scale consisting of none (0), mild (1), moderate (2), moderately severe (3), and severe (4). Pain relief from baseline is evaluated on a five-point scale consisting of none (0), a little (1), some (2), a lot (3), and complete (4). At the end of the first hour of the observation period or at the time of taking supplemental analgesic medication (rescue treatment), whichever occurs first, subjects make an overall (global) asessment of the study medication, based on a five-point scale consisting of poor (0), fair (1), good (2), very good (3), or excellent (4). Subjects are required to remain at the study site for the duration of the four-hour observation period. The primary efficacy assessments are pain intensity differences from baseline and pain relief at each measurement time. Safety is assessed by monitoring adverse events occuring throughout the study. The primary hypotheses are that there is a difference between acetaminophen and placebo and between ibuprofen and placebo at some time point for the proportion of subjects reporting non-zero pain relief.

The patients receive a single oral dose of one of the following three treatments: Two acetaminophen 500 mg caplets and two placebo ibuprofen capsules, two placebo acetaminophen caplets and two ibuprofen 200 mg capsules, or two placebo acetaminophen caplets and two placebo ibuprofen capsules.