Morphometric model, tissue sampling and test of stereologic procedures

SUMMARY Stereologic point counting procedures were applied to estimate volumetric and numerical densities of tissue components residing in and forming a defined, simplified model of human marginal gingiva. This included the quantitative characterization of inflammatory cell infiltrates occurring in the epithelial as well as the connective tissue fractions of this model. The gingival tissue was harvested from defined intraoral sites of 9–15 year‐old children and processed under standardized conditions for light and electron microscopic observation. Random cross‐sections of this tissue were subjected to morphometric analysis based on a multistage sampling technique. At each sampling level, tests were performed to study (1) the suitability of different test systems, (2) the parameter variation within one and between different biopsies and (3) the comparability and reliability of the data obtained. Based on these tests, a morphometric technique was designed which resulted in an accurate estimation of the various parameters characterizing the model tissue. These parameters were the volumetric densities of the following constituents: oral epithelium, junctional epithelium and its leucocyte content, infiltrated and non‐infiltrated connective tissue, and its respective collagen fibre content. Infiltrated and non‐infiltrated connective tissue fractions were analysed for their respective volumetric and numerical densities of fibroblasts, neutrophilic granulocytes, monocytes, macrophages, small and medium‐sized lymphocytes, immunoblasts, plasma cells and mast cells. Sampling technique, test procedures and the design and results of the morphometric system are discussed.