Table 1.

Differential diagnoses for symptoms of black hairy tongue

Discoloration of the tongueDiscoloration of the tongue from food or drugs
Tongue does not appear “hairy”
Oral hairy leukoplakiaLateral tongue plaques with a folded, “feathery” appearance
Associated with HIV and immunocompromised patients
Plaques disappear and reappear spontaneously
Buccal mucosa or gingiva might be involved
Pigmented fungiform papillae of the tongueNormal variant in dark-skinned individuals
Pigmented fungiform papillae along the lateral edges and apex of the tongue
Tongue does not appear “hairy”
Lingua villosa nigra (black hairy tongue)Discoloration of tongue with characteristic “hairy” papillary projections
Mainly involves the dorsal surface of the tongue, where filamentous papillae predominate
Associated with poor oral hygiene
Oral lichen planusChronic autoimmune inflammatory condition affecting the mucosa of the oral cavity
White lacy striations (Wickham striae) found on the buccal mucosa, gingiva, tongue, and lips
Tongue does not appear “hairy” nor darkly pigmented