A black discoloration of the dorsum of the tongue caused by elongated filiform papillae, an accumulation of dark pigments, and an overgrowth of bacteria. It is characterized by a black or brown discoloration of the tongue, giving rise to its name. The cause is unknown but predisposing factors include poor oral hygiene, pigment-producing bacteria or fungi, certain mouthwashes, antibiotic therapy, medications such as bismuth preparations, smoking, drinking tea or coffee, and chewing tobacco. The discoloration can usually be mechanically removed by a tongue scraper or tongue brushing.
Black hairy tongue