title: Gingival pigmentation beneath a metallic crown: light and electron microscopic observations and energy dispersive X-ray analysis.
abstract: Light and electron microscopic studies and energy dispersive X-ray analysis disclosed that the essential cause of gingival discoloration following the placement of a metallic crown, was marked deposition of melanin pigment. Deposition of melanin pigment was observed in epithelial cells, on basement membranes, and in fibroblasts, macrophages and among intercellular ground substance of the proprial layer. Brown or dark brown colored granules were observed in the deep portion of the proprial layer. Some metallic elements as silver and sulfur were detected. It was presumed that these materials were dental metals accidentally implanted in gingival tissues during the therapeutic procedure. The deposition of melanin pigment closely corresponded with mucosal tissue where these materials were present in the deep portion of the proprial layer. These findings suggested that these materials influenced the physiological metabolism of melanin and induced its pathological deposition in the proprial tissue.
authors.affiliation: Department of Prosthetic Dentistry, Faculty of Dentistry, Kyushu University, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Sakai
authors.forename: H
authors.initials: H
authors.lastname: Sakai
authors.forename: N
authors.initials: N
authors.lastname: Hashimoto
authors.forename: R
authors.initials: R
authors.lastname: Hirayasu
mesh_terms: D000328:Adult; D001485:Basement Membrane / Q000473:pathology; D003442:Crowns / Q000009:adverse effects*; D003594:Cytoplasmic Granules / Q000648:ultrastructure; D004577:Electron Probe Microanalysis; D004848:Epithelium / Q000473:pathology; D005260:Female; D005882:Gingival Diseases / Q000209:etiology / Q000473:pathology*; D006801:Humans; D008297:Male; D008544:Melanocytes / Q000473:pathology; D008854:Microscopy, Electron; D008875:Middle Aged; D010859:Pigmentation Disorders / Q000209:etiology / Q000473:pathology*; D012834:Silver / Q000032:analysis
chemical_list: D012834:Silver