Ultrastructure of an odontogenic myxoma.

The ultrastructural findings in a case of odontogenic myxoma are described. The main cell type was characterized by several cytoplasmic processes, intracytoplasmic fibrils, numerous glycogen particles, and salient Golgi complexes. A few mitochondria and a scarce endoplasmic reticulum was noted. The matrix consisted of numerous granules with fibrillar projections, collagen bundles, and smaller fibers. The over-all ultrastructural features of this tumor were similar to those described in the human cardiac myxoma and in Wharton's jelly and could be clearly differentiated from the fine structural characteristics of other connective tissue tumors.