Influence of experimental neutropenia in dogs with chronic gingivitis

Abstract

The influence of a four day period of experimental neutropenia on the clinical state and the structural constituents of chronically inflamed gingiva has been studied in four beagle dogs. Neutropenia was induced by heterologous anti‐neutrophil serum. The effects on the gingiva were evaluated by Gingival Index (GI) and Gingival Exudate measurements and by morphometric analysis of various tissue components in sections from biopsies of buccal gingiva sampled on days 2, 3, and 4. Control biopsies were obtained before induction of neutropenia. The GI did not markedly change during the observation period. The amount of Gingival Exudate, however, significantly decreased following the induction of neutropenia and remained low throughout the experiment. Neutrophilic granulocytes disappeared in the gingival tissues, while, apart from a relative increase in plasma cells, no other tissue components seemed to change. No bacterial invasion of the junctional epithelium or of the gingival connective tissue could be observed. Thus during a four day period the bacterial defense mechanisms at the dentogingival junction seem to be able to prevent penetration of microorganisms into the gingival tissues despite the absence of neutrophilic granulocytes.

A case report of chronic neutropenia: clinical and ultrastructural findings

“…Observation of abundant PMN in the soft tissues contradicts the findings of previous studies of infrequent presence (Kyle & Linman 1970, Reichart & Domow 1978. Deasy et al 1980 or almost complete absence of PMN (Lampert & Fesseler 1975) in the periodontal soft tissues of chronic neutropenic patients, and of neutropenic dogs (Rylander et al 1975). Previous findings were based on light microscopy whereas the present biopsies were examined by TEM.…”

The immunopathogenesis of progressive chronic inflammatory periodontal disease

“…On the other hand, in experimentally induced neutropenia using heterologous anti-neutrophil serum in dogs, Rylander et al (1975) showed that in spite of the complete absence of PMN's from the gingiva, no direct bacterial invasion of the tissues occurred, while in the tissue no change except a relative increase in the numbers of plasma cells was observed. It seems, therefore, that the precise role of gingival sulcus PMN's in chronic inflammatory periodontal disease remains to be ascertained.…”

Modulation of clinical expression of plaque‐induced gingivitis

“…Other systemic conditions identified as affecting the plaque-gingivitis relationship include neutropenia (Andrews et al 1965, Rylander et al 1975, Reichart & Dornow 1978, leukemia (Levin & Kennedy 1973, Bergmann et al 1992, and human immunodeficiency virus/ acquired immune deficiency syndrome (Glick et al 1990). Psychological stress, at least in adults (Deinzer et al 1998, Vanderas et al 1998), leads to heightened gingivitis expression.…”