Periapical actinomycosis.

Actinomycosis is a rare chronic infection caused by species of Actinomyces and characterised by abscess formation, tissue fibrosis, suppurative lesions and fistulas with purulent discharge containing sulphur granules. Owing to its multiform manners of presentation and non-specificity from its clinical features, it has been considered as a challenging diagnosis. Periapical actinomycosis is one of the rarest forms of actinomycosis occurring in the maxillofacial region.