Comparison between histological and clinical parameters during human experimental gingivitis

Abstract

The purpose of this investigation was to study stereologically the histopathologic alterations occurring during a human experimental gingivitis, and to establish a relationship between clinical parameters and histologic findings. Eight dental students volunteered for the study. After a prophylaxis they performed optimal oral hygiene for 3‐4 weeks to reach mean plaque and gingival indices approaching zero. They then abandoned all oral hygiene procedures for a period of 21 days. At d 0, 4, 7, 14 and 21, Plaque Index (PII), Gingival Index (GI) and Gingival Exudate Flow Rate (GEFR) were assessed, and a buccal biopsy of their gingiva was taken. Point counting procedures were performed at 2 different levels of magnification to estimate the volume densities of epithelium, infiltrated and non‐infiltrated connective tissue, and collagen. The percentages of polymorphonuclear neutrophilic granulocytes, lymphocytes, plasma cells, macrophages and fibroblasts were estimated by counting the number of profiles of these cells in the connective tissue area close to the apical end of the junctional epithelium. The histological picture during the entire experiment was one of an early lesion (Page & Schroeder 1976). The clinically healthy gingiva did not correspond to a histologically healthy gingiva containing only a few inflammatory cells, probably because the 3‐4 wk of perfect oral hygiene were not sufficient to generate histological health. Furthermore, no chronic inflammation of the gingiva, as characterized by a predominance of plasma cells, was observed after 3 wk without oral hygiene. Thus, more than 3 wk of no oral hygiene are necessary to obtain an established gingival lesion. With increasing gingivitis scores between GI = 0 and GI = 2 there was a significant increase in the percentages of lymphocytes and a significant decrease in the percentages of fibroblasts. With increasing GEFR similar trends in percentages were observed for lymphocytes and fibroblasts. It was concluded that GI scores and GEFR reflect histologic changes in tissue and, hence, are valid indicators of gingivitis development.

The Effect of Age on the Gingival Crevicular Fluid Composition During Experimental Gingivitis. A Pilot Study

“…Brecx et al (1987) [63] performed an experimental gingivitis study in 8 dental students (a group identical to our young adults) and reported that plasma cells occupied only 1% of the lesions. Differences in the cellular composition of the gingival lesions were also detected by Page et al (1975) [64] in a study in young and old monkeys, and by [35] Berglundh and Lindhe (1993) who investigated developing gingivitis in young and old dogs.…”

Human Memory B Cells in Healthy Gingiva, Gingivitis, and Periodontitis

“…One could speculate that endothelial PNAd and ICAM-1 may be responsible for a sustained recruitment of memory B cells in clinically healthy gingiva. This memory B cell trafficking may take place along with the well-documented polymorphonuclear cell emigration, a well-recognized phenomenon in a clinically healthy sulcus (44,45). Such gingival memory B cells were obviously functional, as they were able to secrete IgG and IgA after in vitro polyclonal stimulation in the current study.…”

Failure of macrophage activation in destructive periodontal disease

“…The additional finding of no significant change in the total macrophage population with the development of experimental gingivitis in humans was also noted by others. 12,13 There have been few reliable phenotypic markers for macrophages available until recently. This limitation has been addressed in part by the development of the high specificity monoclonal antibodies Ber-MAC3, 7 27E10, 8 25F9, 9 and RM3/1.…”