The eosinophilic and amyloid-like materials in adenomatoid odontogenic tumor.

This paper is concerned with the relationship between eosinophilic material (EM) and amyloid-like material and adenomatoid odontogenic tumors. In duct-like structures between opposing rows of tall columnar cells, EM did not stain for amyloid. Under electron microscopy, EM was composed of fibrillar and granular materials, and the fibrillar material was not amyloid. Two different kinds of EM were found in solid cell masses. Lesions from cases 2, 3, 4 and part of case 1 contained small droplet-shaped EM and these EM did not stain for amyloid. Case 1 also contained EM that stained positively for amyloid. The structure of amyloid positive EM resembled developing enamel of human tooth germs. This material was tubular and finely granular. The tubular material resembled enamel matrix fibers rather then amyloid and the fine granular material was stippled. The cells surrounding EM appeared similar to ameloblasts between secretory and maturation stages.