Researchers at the University of Otago, in Dunedin, New Zealand compared impacted third molar extractions in the same patient with and without antibiotic prophylaxis. Ninety-five patients were divided into two groups and served as their own control, receiving antibiotics for one surgery and placebo for the other.
No significant differences were observed between test and placebo for pain, swelling, temperature, or trismus. Post-operative infections occurred in just two percent of the 380 total extractions. Differences between the groups were not significant.