Black hairy tongue

Black hairy tongue is a condition characterized by hypertrophy and hyperkeratosis of the filiform papillae, along with increased local pigmentation due to the action of pigment-producing bacteria or fungi, resulting in a black or brownish-gray appearance of the tongue surface. It is more common in middle-aged individuals, with a higher incidence in males than females, and is rare in children. The main symptom is black "hairs" on the dorsum of the tongue, with the color becoming darker towards the midline.