Collagenolytic activity in oral tissues

Abstract

Live and frozen-thawed explants of guinea pig oral tissue and human gingival tissue were assayed for collagenolytic activity in tissue cultures containing a nutrient medium in a gel of reconstituted collagen fibrils. Live gingival, periodontal and palatal tissues, from young, but not adult, guinea pigs, could all break down the collagen gel; however, collagenolysis was not seen with frozen-thawed explants. This is probably due to extensive tissue remodelling in young animals. Healthy, adult, human tissue did not cause any collagen breakdown but a varying amount was seen with inflamed gingival tissue. While only live, chronically inflamed tissue had collagenolytic ability both live and frozen-thawed explants from patients with acute necrotic gingivitis could break down the collagen gel. In the latter type of inflammation it appears that collagenolytic activity was already present when the tissue was removed from the mouth, whereas in chronic inflammations, tissue culturing was necessary to enhance the amount of collagenolytic factor. An association between collagenolytic ability and the presence of connective tissue is possible, but the possibility that epithelium could be important is not ruled out.