The Location of the Zone of Disintegrating Epithelial Attachment Cuticle

HE epithelial attachment cuticle (eac) is a cuticular membrane which under1 lies the epithelial attachment (ea) and attaches the innermost cells of this tissue to the tooth, whether it is located on the enamel or on the cementum. This cuticle is probably produced or laid down by the cells of the epithelial attachment.1-4 Wherever it is located at any time the outer border of the epithelial attachment cuticle is undergoing more or less breaking down or disintegration and as a result stains heavier than the remaining uninjured portion. This heavier staining line or strip may be demonstrated readily on extracted tooth specimens. Bass5 has called it the zone of disintegrating epithelial attachment cuticle (zdeac). The outer border of the epithelial attachment comes right up to the zone of disintegrating epithelial attachment cuticle but does not overlap it. Therefore this line accurately indicates the location of the outer border of the epithelial attachment at any place around a given tooth specimen. It also accurately indicates the exact extent to which the epithelial attachment cuticle has been destroyed, and is now being destroyed, at any place. The purpose of this paper is to show the location of the zone for disintegrating epithelial attachment cuticle, the cemento-enamel junction (cej), and the outer border of the periodontal fibers (pf) on a number of selected tooth specimens.