HISTOPATHOGENESIS OF ACUTE ULCERATIVE GINGIVITIS

The present study was a preliminary histological and immunofluorescent investigation of the edge of the ulcer in acute ulcerative gingivitis. The results of this study show that the lesion is dominated by polymorphonuclear leukocytes, with plasma cells present in the deeper parts. The epithelium on the edge shows widening of the intercellular spaces with destruction of the epithelial cells, accompanied by a heavy infiltrate of PMNs. Both IgG and C3 could be demonstrated between these epithelial cells, although the present study could not establish whether this represented immune complex deposition. The histopathogenesis of AUG therefore seems to involve a PMN infiltration of the epithelium, with subsequent destruction of the epithelium, probably due to the release of hydrolytic enzymes. The presence of the PMNs within the epithelium may involve direct bacterial chemotaxis and/or the activation of complement via the classical or alternative pathways.