Ultrastructure of odontogenic jaw cysts.

The epithelial ultrastructure of six radicular cysts, four follicular cysts, and five keratocysts was studied with special attention to the epithelium-connective tissue junction. Inflammation was found to cause widened interepithelial cell spaces which often harbored inflammatory cells in the radicular and follicular cysts. The characteristic structures at the epithelium-connective tissue junction (plasma membrane, lamina lucida and basal lamina) were not affected by inflammation. Fibrous structures were seen to connect the basal lamina to the underlining collagenous connective tissue. The keratocyst specimens, however, showed juxtaepithelial collagenolysis that was not associated with the degree of inflammation. Desmosomes were rare in the inflamed keratocysts' spinous layer but the cell-to-cell interactions still appeared close. Inflammatory cells were not detected within epithelium of the keratocyst specimens.