“…Risk factors includes poor dental hygiene or dental caries, pre existing structural lung disease, chronic alcoholism and cognitive delay 11,12 . Inhalation of contaminated aerosol particles or aspiration of oropharyngeal or gastrointestinal secretions, or hematogenous spread from a distant lesion is the mechanisms for pulmonary actinomycosis 13,14 . In our case the patient had a history of mandible fracture and tooth extraction two years before the onset of illness and had poor oral hygiene with severe caries, so secondary aspiration might have been the mechanism of infection.…”