Effect of azidocillin, erythromycin, clindamycin and doxycycline on postoperative complications after surgical removal of impacted mandibular third molars.

Treatment of osteitis after surgical removal of the third molar of the mandible is still a clinical problem. A total of 140 patients undergoing operations for removal of an impacted third molar of the mandible, were included in a double-blind study. Placebo or antibiotics - azidocillin, erythromycin, clindamycin and doxycycline - were given to the patients preoperatively and for the following 7 days. The concentrations in serum, alveolar serum and mandibular bone were measured and the postoperative courses - pain, trismus, swelling and wound-healing - were recorded. No correlation was obtained between the antibiotic concentration and the postoperative complaints, except in the azidocillin group on day 2, in which fewer complaints were noticed in patients with high concentrations of the drug at the time of operations. The 80 patients in the antibiotic groups responded significantly better with respect to wound-healing than the 60 patients in the placebo groups. Only 15 operations lasted more than 15 min and the three of them which subsequently resulted in alveolitis were in the placebo groups. Antibiotics significantly reduced pain on day 7 postoperatively. In general, no statistically significant differences in trismus and swelling could be demonstrated between the patient groups. However, there was a significant difference between the placebo and doxycycline groups with respect to swelling (day 2 postoperative, P < 0.01; day 5 postoperative, P < 0.05). Thus systemically administered antibiotics offered only slight advantages in routine operations of impacted third mandibular molars, but could decrease the rate of infections after traumatic operations.