Bacterial Factors in Nonspecific Gingivitis

Abstract

A differential count in different regions of the human gingival area and the tooth surface in 25 individuals with nonspecific marginal gingivitis and 10 patients with clinically normal gingivae revealed a definite pattern of distribution of various bacterial types. In nonspecific gingivitis there was an increase in total number of organisms in all areas and a relative increase in the percentages of spirochetes, fusiforms, and vibrios, as well as gram-negative cocci. Injection and aspiration of saline solution in the gingiva and the study of stained sections for bacteria failed to reveal bacteria in the deeper gingival tissues. To determine whether products of bacterial activity can cause gingival inflammation, bacteria-free filtrates were prepared from bacteria collected from the gingival margin, by freezing and thawing or filtration through sintered glass. Some of the filtrates thus prepared gave hyperemic reactions in sensitized rabbit skin. In most tests, filtrates produced spreading of carbon particles in rabbit skin which corresponded with that produced by hya-luronidase. The mechanism of the production of gingivitis by bacteria is discussed.