Dexamethasone injection into the pterygomandibular space in lower third molar surgery

The objective of this study was to evaluate the effects of 8mg dexamethasone injection into the pterygomandibular space on the postoperative sequelae of lower third molar surgery. A prospective, randomized, controlled, split-mouth study was designed involving 62 lower third molar extractions (31 patients). Prior to surgery, the study group received 2ml of 4mg/ml (8mg) dexamethasone injection through the pterygomandibular space following local anaesthesia; the control group received 2ml normal saline injection. Facial swelling, mouth opening, pain on a visual analogue scale (VAS), and the number of analgesics consumed were assessed. Descriptive statistics and the independent-samples t-test were used to compare the two groups at P<0.05. There was a significant reduction in swelling on day 2 postoperative in the dexamethasone group. Mouth opening was also significantly greater on day 2 in the dexamethasone group. The VAS pain score was significantly lower on the day of the operation and first postoperative day in the dexamethasone group, but did not differ significantly between the groups on the other postoperative days. The injection of 8mg dexamethasone into the pterygomandibular space was effective in reducing postoperative swelling, limited mouth opening, and pain following impacted lower third molar extraction.