Cholesterol Crystals in Odontogenic Cysts: An In-Depth Narrative of Pathogenesis

Abstract

Cholesterol crystals (CCs) are a relatively common finding in infected odontogenic cysts occurring in about 60% of the cases. Histopathologically, these appear as longitudinal cleft-like spaces or may appear as a collection in cholesterol granulomata. The occurrence of CCs in odontogenic cysts is closely associated with the pathophysiology of the lesions. Despite being fairly common, not much is known about the sources of cholesterol, the mechanism of formation of these clefts, their pathogenesis, and their clinical implications. The present article focuses on describing CCs with respect to their contents, pathogenesis, and clinical implications. Our review describes the mechanism of the formation of CCs in a detailed manner along with a pictorial depiction of the cascade of events involved in the process. The formation of cholesterol granulomata is a cumulative effect of the breakdown of erythrocytes and leukocytes, intramural hemorrhage, decreased blood supply and lymphatic drainage, hypoxic conditions, increased vascular permeability, accumulation and rupture of lipid-laden macrophages, and foreign body reaction. It would be of great interest to pathologists to have an in-depth understanding of the pathogenesis, nature, and implications of CCs, which are very common yet enigmatic entities.