Antibiotic prophylaxis for orthognathic surgery: a prospective, randomised clinical trial.

A prospective, randomised, placebo-controlled double-blind clinical trial, compared short-term (1 day) and long-term (5 days) antibiotic prophylaxis after orthognathic surgery. Thirty four patients had single jaw or bimaxillary osteotomies and were given two perioperative doses of amoxycillin. Patients were then randomised to receive either placebo or amoxycillin for 5 days in a double-blind manner. Postoperatively the patients were monitored for infection by scoring a series of validated measurements of infection. In the postoperative period four patients required additional antibiotics in the short-term group and two in the long-term group (P = 0.67). Morbidity scores were higher in the short-term group, at 406 to 264 (P = 0.04), and when individual variables were compared there was a significant difference in the degree of swelling (P = 0.04). Although a 5-day regimen of antibiotic prophylaxis in orthognathic surgery did not decrease the incidence of postoperative infection significantly, it may decrease the morbidity of the operation.