Effects of gold salts on experimental periodontitis. III. Ultrastructural observations

Previous studies showed that the systemic administration of soluble gold salts resulted in significantly less periodontal destruction after 2 weeks of experimentally induced periodontitis. The present study compared the ultrastructural characteristics of the inflammatory lesion in animals receiving gold salts (experimental) with those in animals that had not received gold salts (control). Maxillary gingival biopsy specimens were obtained from the buccal aspect of ligatured teeth after 2 weeks of experimental periodontitis. A cellular and extracellular ultrastructural characterization was done in an "epithelial and superficial connective-tissue zone," and a "deep connective-tissue zone." Experimental (gold-receiving) specimens had an intact sulcular epithelium with narrow intercellular spaces overlying a collagen dense connective tissue. Control specimens had a degenerating disrupted epithelium overlying a collagen-poor connective tissue in which polymorphonuclear leucocytes predominated and often were closely apposed to morphologically altered fibroblasts. The cellular distribution of electron-dense deposits of gold salts was demonstrated, and their possible role in modulating mechanisms of cell cytotoxicity and collagen turnover is discussed.