Pain Control After Orthognathic Surgery

This study will assess the efficacy and safety of levobupivacaine for postoperative pain control in patients received orthognathic surgery. In this split-mouth study, each side will be randomized to receive 1) 5ml 0.5% levobupivacine, 2) 2.5ml 0.5% levobupivacaine, or 3) placebo. One shot of these agents will be delivered by nerve block to maxillary and mandibular branches of trigeminal nerve before the incision was made. The degree of postoperative pain will be evaluated daily by visual analog scale for up to 3 days. The anticipated time on study is 1 year, and the target sample size is 40 individuals.