Unknown to a rare known: A case report of apical actinomycosis

Actinomycosis is a rare infection caused by filamentous Actinomyces, which form club-shaped filaments arranged in a radiating pattern and rarely infects jawbone. Due to its nonspecificity from its clinical features, it has been considered as a challenging diagnosis. This case report describes a case of periapical cyst which was diagnosed as actinomycosis based on histopathological examination. Periapical actinomycosis is one of the most important reasons for the failure of nonsurgical treatment. Clinically, if the periapical lesion is largely associated with weeping canals, surgical debridement of granulation tissue is mandatory. In this case, surgical intervention and adjunctive platelet rich fibrin with osseograft provided successful healing.