title: Urea content of gingival crevice fluid and its relationship to periodontal disease in humans.
mesh_terms: D005122:Exudates and Transudates / Q000032:analysis; D009584:Nitrogen / Q000032:analysis; D010510:Periodontal Diseases / Q000276:immunology; D010950:Plasma Cells; D014508:Urea / Q000032:analysis
chemical_list: D014508:Urea; D009584:Nitrogen