Are postoperative intravenous antibiotics necessary after bimaxillary orthognathic surgery? A prospective, randomized, double-blind, placebo-controlled clinical trial.

Postoperative antibiotic prophylaxis is often administered intravenously, despite an increased morbidity rate compared with oral application. This study investigates whether a postoperative oral antibiotic regimen is as effective as incorporation of intravenous antibiotics after bimaxillary orthognathic surgery. 42 patients who underwent bimaxillary orthognathic surgery between December 2008 and May 2010 were randomly allocated to 2 placebo-controlled postoperative antibiotic prophylaxis groups. Group 1 received oral amoxicillin 500mg three times daily; group 2 received intravenous ampicillin 1g four times daily, during the first two postoperative days. Both groups subsequently took oral amoxicillin for three more days. Clinically, the infection rate was assessed in both study groups for a period of 6 weeks after the surgery. 9 patients (21.4%) developed infection. No adverse drug event was detected. No significant difference (p=0.45) was detected in the infection rate between group 1 (3/21) and group 2 (6/21). Age, type of surgical procedures, duration of the operative procedure, surgical procedure-related events, blood loss, and blood transfusion were all found not related to infection (p>0.05). Administration of more cost-effective oral antibiotic prophylaxis, which causes less comorbidity, can be considered to be safe in bimaxillary orthognathic surgery with segmentalizations.