title: Biochemical studies on the composition of gingival debris from children with black extrinsic tooth stain.
mesh_terms: D000293:Adolescent; D000328:Adult; D002118:Calcium / Q000032:analysis; D003728:Dental Calculus / Q000032:analysis; D003741:Dental Deposits / Q000032:analysis*; D005881:Gingiva; D006801:Humans; D010710:Phosphates / Q000032:analysis; D014075:Tooth Discoloration / Q000378:metabolism*
chemical_list: D010710:Phosphates; D002118:Calcium