Abstract
A case of calcifying odontogenic cyst associated with complex and compound odontoma which appeared in the maxilla of a 15-year-o1d Japanese girl was reported with immunohistological examination. Radiologically, the lesion showed a cystic radiolucent area with odontoma-like radiopaque masses. Histopathological examination revealed the presence of ghost cells, calcified tissues and structures of complex and compound odontoma. Immunohistochemically, MIB-1 positive ratio was very low, but significant expression of Bcl-2 was observed in the neoplastic odontogenic epithelium. These results suggest that inhibition of apoptotic cell loss is more important than cell proliferation activity to the growth of the lesion in our case.