Morphology of a simple ameloblastoma related to the human enamel organ.

The ultrastructure of a simple ameloblastoma was investigated. The epithelial cells of the tumor could be divided into peripheral cells of varying height, and dark and light central cells. The morphology was correlated to that of the human enamel organ. The low peripheral cells were very similar to the external enamel epithelium cells. The central cells had a certain resemblance to the stellate reticulum and stratum intermedium cells. The high peripheral cells had no counterparts in the enamel organ. Unlike the enamel organ the ameloblastoma showed extremely few and small gap junctions.