All oral surgeions have encountered problems associated with edema, trismus, and pain after intraoral procedures. In third-molar surgery, pain and trismus are often directly proportional to edema. Therefore, in the patient with minimal edema, pain and trismus should be proportionally reduced. Parenteral use of the corticosteroid dexamethasone, given as a transoral injection at the time of operation, appears to be effective in the prevention of postoperative edema.