Cervicofacial actinomycosis and mandibular osteomyelitis.

Cervicofacial actinomycosis should be included in the differential diagnosis of any soft tissue swelling in the head and neck region, particularly if malignancy or a granulomatous disease is suspected. The diagnosis often is overlooked because of this entity's ability to mimic other conditions. Mandibular osteomyelitis also is underappreciated by many clinicians in their assessment of head and neck infections. Most cases are traced to an odontogenic source, with periapical tooth abscess and posttraumatic or surgical complication as key antecedent events.