The composition of gingival inflammatory cell infiltrates in children studied by enzyme histochemistry.

Gingival biopsies were obtained from 23 children, aged 5-11 years (8.6 +/- 1.8 years). Specimens were taken from areas of the gingiva adjacent to the teeth which were to be extracted because of caries or its sequelae and which clinically had a gingival index score of at least 1. Staining for alpha-naphthyl acetate esterase with unspecific esterase at pH 5.8 (ANAE) permitted identification of T lymphocytes, monocytes/macrophages, plasma cells and non-reactive (ANAE-negative) cells. Cells which tentatively were identified as "natural killer" (NK) cells were also observed. Differential cell counting was performed for 10 specimens, selected on the basis of the presence of a well-defined inflammatory infiltrate, clear morphology throughout and good ANAE staining. Cell counts confirmed earlier studies showing that lymphocytes predominate in the inflammatory infiltrates in childrens' gingivitis. T lymphocytes dominated particularly in the periphery of the most densely infiltrated areas. Relatively few plasma cells were seen. It was concluded that T lymphocytes dominate in the inflammatory infiltrate in childrens' gingivitis.