[Ultrastructure of hyperpigmented gingiva due to metallic deposits from dental restorations]

An ultrastructural study of hyperpigmented gingival fragments due to metallic deposits, originating from fixed or amalgam restorations, has shown the presence of metallic particles in the lamina propria either in extracellular locations between collagen fibrils, in basal lamina of gingival keratinocytes, endothelial cells and Schwann cells, or in intracellular locations in macrophages, fibroblasts or endothelial cells.