Periapical actinomycosis. Report of a case and review of the literature.

An analysis of actinomycosis in periapical inflammatory lesions in the English-language literature was carried out. Nineteen cases were found, and an additional case is presented. The most frequent locations for these infections were the maxillary central incisor region and the mandibular first molar region. The average age of the patients was 27.5 years, and a slight male predilection was noted. Formation of draining sinuses, local swelling, and pain were the most common presenting symptoms. Many of the cases were diagnosed following endodontic procedures, suggesting that such procedures might be responsible for introducing the organisms into the periapical tissues or that the organisms might be responsible for some cases of endodontic failure.