Specialized postcapillary venules in human gingival tissue.

High endothelial venules (HEV) are specialized postcapillary venules that play a central role in lymphocyte migration and recirculation. This study examined the occurrence and morphology of HEV-like vessels in healthy gingiva and in lesions of chronic gingivitis in children, experimental gingivitis in adults, adult periodontitis, and in periapical granulomas. HEV-like vessels were absent in gingival health, but present during the development of inflammation and in chronic inflammation. The morphology of these HEV-like vessels in the oral cavity resembled that of lymphoid HEV. Thus gingival HEV may represent sites for the entry of lymphocytes into chronic inflammatory lesions.

Hereditary gingival fibromatosis associated with hearing loss and supernumerary teeth--a new syndrome.

Hereditary gingival fibromatosis can occur as an isolated trait or as part of a syndrome. We report on three generations of one family featuring an autosomal dominant syndrome with variable expression of gingival fibromatosis with associated hearing deficiencies, hypertelorism, and supernumerary teeth. We propose that this represents a new syndrome within the spectrum of those including gingival enlargement.

In situ demonstration of natural killer (NK) cells in human gingival tissue.

Recent studies have raised the possibility that natural killer (NK) cell activity may play a role in tissue destruction in chronic inflammatory periodontal disease (CIPD). This study aimed to locate and identify these cells in healthy and diseased gingival tissue. Leu 4, Leu 7, and Leu 11 monoclonal antibodies were used to characterize lesions of CIPD and to identify NK cells. Gingival tissue from three patient groups was examined. Group 1 subjects participated in a 21-day experimental gingivitis study. Group 2 subjects were children aged less than 8 years who had gingivitis associated with deciduous teeth. Group 3 consisted of patients with CIPD undergoing periodontal surgery. In group 1, NK cells were absent in health (Day 0) and gradually increased in number with increasing inflammation up to Day 21. The number and distribution of NK cells in Group 2 subjects resembled those seen after a 21-day experimental gingivitis study. In Group 3 subjects, lesions of CIPD which contained greater than 90% Leu 4+ cells ("T cell" lesions) contained few Leu 7+ cells and no Leu 11+ cells. The greatest number of NK cells were found in the "B cell" lesions (less than 60% Leu 4+ cells). The absence of NK cells in gingival health and their presence in diseased gingiva suggests that these cells are involved in the immune response to the accumulation of plaque.