What is the predominant cell type found in the exudate draining from a chronic dental abscess sinus tract (fistula)?

Chronic inflammation is characterized by the predominance of mononuclear cells: lymphocytes, macrophages, and plasma cells. A chronic dental abscess with a sinus tract (fistula) represents a long-standing, established infection where the acute inflammatory phase (dominated by neutrophils) has resolved into a chronic state. Neutrophils predominate in acute infections and acute abscesses. In chronic lesions, the cellular infiltrate shifts to lymphocytes and macrophages, with plasma cells also present as part of the adaptive immune response.