Enzyme histochemical studies on the formation of hyalin bodies in the epithelium of odontogenic cysts.

: Frozen sections of eight odontogenic cysts, including one keratocyst, were incubated to show the following enzyme activities: NADH2 diaphorase, NADPH2 diaphorase, glucose-6-phosphate dehydrogenase, acid phosphatase and leucinc aminopeptidase. The distribution of lipid was shown by the oil red 0 method. The activities of all three oxidative enzymes were strongest in epithelial cells bordering hyalin bodies and in basal cells in the epithelial lining. Hydrolytic enzyme activity was absent from all but the most superficial epithelial cells but was present in macrophages and, in lesser amounts, in granular material in the same sections. The granular material frequently contained lipid. The lack of hydrolytic enzyme activity in bordering epithelial cells is inconsistent with the theory that hyalin bodies form from degenerating blood vessels. High aerobic oxidative enzyme activity in the same cells also conflicts with the concept that the bodies are a keratinous product. The findings lend support to the theory that hyalin bodies are an epithelial secretion.