Histopathological Investigation of Gingival Tissue From Patients With Rapidly Progressive Periodontitis

Abstract

In this study, fine structural features of the pocket walls in rapidly progressive periodontitis (RPP) and adult periodontitis (AP) in 20 cases were compared using light and transmission electron microscopy. Gingiva was also obtained from a control group of periodontally healthy teeth. Clinical parameters were assessed in both RPP and AP patients and in controls. Bone destruction and attachment loss were more marked in RPP than in AP. Light microscopical observations of inflamed RPP tissue as compared to AP showed gross histological distortions in the pocket walls. Micro‐ridges within the epithelium and large intercellular spaces between the epithelial cells were observed in most RPP biopsies. Epithelial cells surrounding the microclefts and adjacent keratinocytes were found to produce interleukin‐1β (IL‐1β). Prevotella intermedia and Porphyromonas gingivalis were identified in the RPP biopsies using immunohistological methods. These microorganisms were localized outside the epithelium and inside intercellular spaces. Furthermore, the effect of inflammation on the distribution of collagen types I, III, IV, V, and VI in the human gingiva was studied after staining them with antibodies to these proteins. In RPP and AP tissues, the staining was sparse in areas of inflammation and leukocytic infiltration. Collagen type I and III were almost entirely lost at sites of inflammation. Type V and VI collagen antibodies were retained in inflamed areas. Type IV collagen was restricted to basement membrane structures. These observations demonstrated numerous structural features indicative of more pronounced degenerative changes in RPP than in AP. J Periodontol 1998;69:195–208.

Calprotectin Expression In Vitro by Oral Epithelial Cells Confers Resistance to Infection byPorphyromonas gingivalis

“…P. gingivalis, a key putative periodontal pathogen, can invade the gingival tissue in advanced periodontitis (19,39) and invade cultured epithelial cells in vitro (25,41). P. gingivalis also produces enzymes that degrade a broad spectrum of host proteins, including epithelial adhesion molecules (22,48) and extracellular matrix proteins (44).…”

The role of macrophages in the induction of murine immune response to Actinobacillus actinomycetemcomitans

“…It has been shown that macrophages in the gingival epithelial surface beneath periodontal pockets engulf Porphyromonas gingivalis in situ [12]. P. gingivalis-induced phagocytic activity by murine macrophages has been found to be enhanced by interferon (IFN)-ª, but not IL-4 and IL-10 [13].…”

Nuclear Targeting ofPorphyromonas gingivalisW50 Protease in Epithelial Cells

“…The organism can invade gingival tissue in advanced periodontitis (18) and can be taken up by gingival and pocket epithelial cells, oral epithelial cell lines, and endothelial cells in vitro (13,23,33,40). The nature of the eukaryotic surface receptor molecules and the signal transduction pathways required for internalization of P. gingivalis by oral epithelial cells remain to be clarified.…”