elastin and Gingival-Hyperplasia

Eight specimens each of the following groups were investigated: gingival pyogenic granuloma, fibrous epulis, calcifying fibrous epulis, peripheral giant cell granuloma, giant cell fibroma (four gingival, four non-gingival), denture-irritation hyperplasia and fibroepithelial polyp. These lesions have diverse histopathological appearances but the composition of their connective tissue is poorly defined. The elastic system consists of a complex mixture of glycoproteins that in normal oral mucosa form three differentially distributed fibre types; oxytalan, elaunin and elastic. The elastic system was investigated by Verhoeff's haematoxylin stain, aldehyde fuchsin staining and an anti-elastin monoclonal antibody. Elastin was identified in all fibroepithelial polyps and denture-irritation hyperplasias, but in none of the other lesions. In particular, this identified a distinct difference in the extracellular matrix between the giant cell fibroma and fibroepithelial polyp. Many of the epulides included only oxytalan fibres, but the presence of oxytalan fibres did not follow any pattern within either a single lesion group, or between different lesions. However, the presence of oxytalan fibres in the absence of elastin does not necessarily support a periodontal ligament origin for reactive epulides.

Topics: Antibodies, Monoclonal; Diagnosis, Differential; Elastic Tissue; Elastin; Fibroma; Gingival Diseases; Gingival Hyperplasia; Gingival Neoplasms; Gingival Overgrowth; Granuloma, Giant Cell; Granuloma, Pyogenic; Hematoxylin; Humans; Immunohistochemistry; Mouth Mucosa; Polyps; Rosaniline Dyes; Stomatitis, Denture

It is generally agreed that gingival overgrowth results from an increase in the levels of gingival extracellular macromolecules infiltrated with various numbers of inflammatory cells. The relative amounts of extracellular matrix macromolecules observed in 12 cases of gingival hyperplasia associated with the use of cyclosporin, hydantoin or nifedipine were compared with those obtained in a control group on the basis of histological and immunohistochemical investigations. From tissue sections, the quantification was by computerized morphometric analysis on a BFM 186 microcomputer to which were implemented the transformations of mathematical morphology. The area fractions (AA%) occupied by total collagen, type III and type IV collagen, vessels, fibroblasts, fibronectin and elastic fibres were estimated and compared. The overall histological aspects of drug-induced gingival overgrowth were similar, but quantification of different extracellular matrix components showed differences. In the nifedipine and cyclosporin groups, the area occupied by fibroblasts were not significantly greater than in healthy gingiva and chronic gingivitis. The area occupied by collagen was significantly greater in the nifedipine group than in the other pathological groups. Fibronectin was also strongly expressed in the nifedipine group, and the elastic fibre network was preserved in this group.

Topics: Collagen; Cyclosporine; Elastic Tissue; Elastin; Extracellular Matrix; Extracellular Matrix Proteins; Female; Fibroblasts; Fibronectins; Gingival Hyperplasia; Humans; Hydantoins; Male; Microscopy, Video; Nifedipine; Nitrendipine; Signal Processing, Computer-Assisted; Statistics, Nonparametric