Hyaline bodies in ameloblastoma: histological and ultrastructural observations.

An exceedingly rare case of ameloblastoma, plexiform type, which contained numerous hyaline bodies was reported. Hyaline bodies occurred within the parenchyma, and showed similar histochemical reactions to those of hyaline bodies in odontogenic cysts. Ultrastructurally, hyaline bodies found in the present case of ameloblastoma were composed of a peripheral electron-dense area and central electron-lucent area. Well-developed endoplasmic reticulum containing electronlucent and homogeneous substance were seen in the epithelial cells adjacent to hyaline bodies. Furthermore, electron-dense spherical granules, with or without limiting membrane, were scattered in the cytoplasm of epithelial cells. It is thought that hyaline bodies in the present case of ameloblastoma are particular products formed by odontogenic epithelial cells.