What’s this?

This is black hairy tongue

Hairy tongue, known medically as lingua villosa nigra, is a benign and usually transient condition characterized by the elongation and discoloration of the filiform papillae on the dorsal surface of the tongue. This elongation occurs due to the accumulation of keratin, debris and microorganisms, leading to a hairy appearance (DermNet, 2014).

The condition is often associated with factors such as poor oral hygiene, tobacco use, excessive consumption of coffee or tea, certain medications (such as antibiotics or medications causing dry mouth) and reduced salivary flow.

The filiform papillae, responsible for the mechanical cleansing of the tongue surface, fail to undergo the normal desquamation (shedding) process, leading to hypertrophy. Then in addition to these changes, pigments from food, drinks, tobacco, or bacterial and fungal overgrowth can stain the elongated papillae, causing visible discoloration (Patil et al., 2009). Hairy tongue is usually asymptomatic but can cause a sensation of fullness, metallic taste, halitosis or gagging in some individuals.

Diagnosis is primarily clinical and based on the presence of risk factors and the characteristic appearance of the tongue. Management involves addressing the underlying causes and improving oral hygiene practices. This includes regular tongue cleaning or brushing with a soft toothbrush to remove the accumulated debris and bacteria. Maintaining proper hydration and avoiding contributory factors, such as tobacco and excessive consumption of staining substances, are essential preventive measures.

A specific intervention may be necessary in rare cases where the persistent hairy tongue causes significant discomfort. Dentists or other providers can prescribe topical treatments, such as antifungal or keratolytic agents, to facilitate the removal of the accumulated debris and restore normal tongue morphology. Addressing the underlying factors, such as modifying medications or managing systemic conditions contributing to reduced salivary flow, is crucial in managing persistent cases of hairy tongue.

Differential diagnosis includes hairy leucoplakia, a painless white lesion commonly found on the lateral margin of the tongue, often asymmetrically. This condition is common in immunocompromised patients and can also occur on other oral surfaces, such as the buccal mucosa and gingiva (Rathee, 2023). Oral Acanthosis nigricans could appear as pigmented papules on the tongue and usually involves lips. This manifestation is closely associated with underlying malignancies.

In summary, a hairy tongue is a benign and manageable condition characterized by the elongation and discoloration of filiform papillae on the tongue’s surface. A comprehensive understanding of its aetiologies with appropriate interventions, including maintenance of optimal oral hygiene and addressing contributory factors, forms the cornerstone of the medical management.