title: Histopathologic features of the initial and early stages of experimental gingivitis in man.
abstract: The pathologic alterations occurring in the gingival tissues of humans immediately following the beginning of plaque accumulation have not heen elucidated previously.  Seven males, 22--31 years of age, free of clinical manifestations of dental and periodontal disease, and exhibiting a Plaque Index score of zero for the previous 28 days served as subjects.  Plaque control measures were discontinued for 8 days and biopsies were taken from the buccal marginal gingiva of the first premolars on days 0, 2, 4, and 8.  Paraffin- and Epon-embedded section, treated with a variety of histochemical stains were analyzed microscopically and cell counts were done on 1-micron Epon section.  At 2 and 4 days following the beginning of plaque accumulation, the vessels subjacent to the juctional epithelium exhibited vasculitis and alterations in the perivascular collagen.  There was a statistically significant increase in the number of neutrophils residing in the junctional epithelium.  By the end of the 8-day period, the number of small mononuclear cells, mostly lymphocytes, in the connective tissues had increased by 3-fold and the area of collagen fiber alteration by 4-fold.  In addition, the number of fibroblasts per unit area of connective tissue decreased significantly.  Thus, within the period of 8 days following the beginning of plaque accumulation, an early lesion exhibiting many features characteristic of delayed hypersensitivity develops.
mesh_terms: D000328:Adult; D001706:Biopsy; D003773:Dental Plaque / Q000473:pathology; D005891:Gingivitis / Q000473:pathology*; D006801:Humans; D008297:Male; D013997:Time Factors