Hairy Tongue

Hairy tongue (lingua villosa) is a commonly observed condition of defective desquamation of the filiform papillae that results from a variety of precipitating factors. In hairy tongue the lesion does not consist simply of a coating on the surface of the tongue but represents an elongation of the filiform papillae, often to many times their original length. With this elongation the papillae often take on a dark colour, black or brown being common. The mechanism for the formation of these coloured hairy tongues is quite unknown, there apparently being many initiating factors. For instance, hairy tongue frequently follows a course of antibiotic therapy and may resolve quite rapidly on completion of treatment. Other hairy tongues apparently appear completely spontaneously and no cause is ever found for them. Equally doubtful is the source of the pigment involved. It is usual to relate this to pigment-producing organisms entrapped within the papillae but, in fact, no such organisms have ever been demonstrated. In the past, the presence of hairy tongue was often ascribed to candidal infection but, again, it has never been shown that there is any true association between candidosis and the production of the elongated papillae.

Treatment of hairy tongue is remarkably difficult. Those cases associated with antibiotic therapy frequently, but not invariably, resolve when the medication is finished. The use of effervescent and mucus-solvent mouthwashes may be helpful in reducing secondary irritation and thereby producing suitable conditions for the resolution of the abnormality but, again, the results are variable. The authors have used chemical cauterization, with trichloracetic acid, to treat hairy tongue, but only small areas can be managed at a time, because of discomfort afterwards. Long-term results of this chemical counterization were disappointing. "Sucking a dry peach stone" has been advocated for the management of hairy tongue but this approach does seem to be potentially hazardous! Some patients with this condition use tongue scrapers or brush their tongue vigorously but these measures are rarely effective. 

 
Source :
Field A. 2003. Tyldesley's Oral Medicine. Vol. 5th Ed. Oxford University Press. UK
http://emedicine.medscape.com/article/1075886-overview 
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