Metronidazole for the prevention of dry socket after removal of partially impacted mandibular third molar: a randomised controlled trial

We randomised 119 patients who had been referred for removal of partially impacted mandibular third molars to be given either metronidazole 1600 mg or placebo as a single dose 45 min before operation. Ten of the fifty-nine patients who were given metronidazole and 13 of the 60 given placebo developed dry sockets. Two variables were significantly associated with the development of a dry socket: pericoronitis and oral conceptives.