Smoker's melanosis is seen with the naked eye as a brown to black pigmentation of the oral tissue i.e. the gums, cheeks or palate Axéll T, Hedin CA: Epidemiologic study of excessive oral

melanin Melanin (; from el, μέλας, melas, black, dark) is a broad term for a group of natural pigments found in most organisms. Eumelanin is produced through a multistage chemical process known as melanogenesis, where the oxidation of the amino ...

pigmentation with special reference to the influence of tobacco habits. Scand J Dent Res 1982; 90:434-442. as well as in larynx. It is most often seen in the lower labial gingiva of

tobacco Tobacco is the common name of several plants in the genus '' Nicotiana'' of the family Solanaceae, and the general term for any product prepared from the cured leaves of these plants. More than 70 species of tobacco are known, but the ...

users. Most easily it is found in Caucasians, due to their lack of a genetically caused

pigmentation.Hedin CA: Smoker's Melanosis. Occurrence and localization in the attached gingiva. Arch Dermatol 1977; 113:1533-1538. The brown to black colour is melanin. In skin, melanin prevents harmful UV-light from reaching deeper, sensible parts of the tissue. If UV-light penetrates deep, some of the toxic substances due to the UV-light damage to the cells, are bound to melanin in the

epithelial cells Epithelium or epithelial tissue is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. It is a thin, continuous, protective layer of compactly packed cells with a little intercellula ...

and travel with the ageing cells to the skin surface, where they are expelled from the tissue surface. In this way the

melanocyte Melanocytes are melanin-producing neural crest-derived cells located in the bottom layer (the stratum basale) of the skin's epidermis, the middle layer of the eye (the uvea), the inner ear, vaginal epithelium, meninges, bones, and heart. ...

s and

keratinocyte Keratinocytes are the primary type of Cell (biology), cell found in the epidermis (skin), epidermis, the outermost layer of the skin. In humans, they constitute 90% of epidermal skin cells. Basal cells in the stratum basale, basal layer (''str ...

s together protect the tissue, with melanin serving as a toxic defence and cleaning agent. In the oral mucosa, where the ageing epithelial cells move faster to the surface compared to skin, a similar defence-mechanism seems to be present, cleaning the mucosa from different toxic chemicals penetrating the epithelium. Besides chemicals in tobacco also antimalaria-drugs cause an oral pigmentation. Smoker's melanosis is like the genetic melanin pigmentations, a defence-system in action. The microscope shows smoker's melanosis to be characterized by a melanin hyperpigmentation of the lower part of the oral epithelium, similar to sun-tanned skin. The hyperpigmentation consists of melanin granules which have the shape and colour of "coffea beans". They are produced by the dendritic, octopus-like melanocytes, seen between the epithelial cells situated closest to the epithelium/connective tissue border. In tobacco-users the melanocytes are stimulated to produce melanin granules and to distribute them out to the surrounding epithelial cells for further transport to the mucosal surface, like the mechanism in melanin-pigmented skin. Small amounts of melanin-like granules together with other electron-dense particles can also be seen within large melanosome complexes in the underlying connective tissue. If the granules derive from the epithelium, a phenomenon known as melanin incontinence, is not known. In Caucasians these granules are not expected to influence on the clinically observed degree of smoker's melanosis.

Causes

Smoking or the use of

nicotine Nicotine is a natural product, naturally produced alkaloid in the nightshade family of plants (most predominantly in tobacco and ''Duboisia hopwoodii'') and is widely used recreational drug use, recreationally as a stimulant and anxiolytic. As ...

-containing drugs is the cause to Smoker's melanosis,.Wallstrom M, Sand L, Nilsson F, Hirsch JM: The long-term effect of nicotine on the oral mucosa. Addiction 1999; 94:417-423. Also tar-components (benzopyrenes) are known to stimulate melanocytes to melanin production, and other unknown toxic agents in tobacco may also be the cause. These chemical agents have a polycyclic, chain-like structure. Environmental tobacco smoke from parents is causing smoker's melanosis in their children Swedish snuff causes a small elevation of oral melanin pigmented individuals from 3.0% to 4.7%. Nicotine tablets have shown to stimulate to melanin pigmentation of the oral mucosa.

Treatment and prognosis

Lesions usually disappear between 3 months to 3 years for those who stop smoking. Smoker's melanosis is a benign, normal physiological reaction, and does not develop into cancer. If it does not disappear, however, a

biopsy A biopsy is a medical test commonly performed by a surgeon, interventional radiologist, or an interventional cardiologist. The process involves extraction of sample cells or tissues for examination to determine the presence or extent of a diseas ...

can verify the diagnosis. If Smoker's melanosis is destroyed by excessive smoking, as in the hard palate of reverse smokers, who smoke with the glowing part of the cigarette inside the mouth for different reasons, a pale depigmented surface is first seen, indicating the loss of the protecting melanin. Then a red inflammation sometimes occurs and cancer development may follow. In reverse smokers it is important to regularly inspect the areas with Smoker's melanosis to detect any melanin destruction, in order to stop smoking in time and thus prevent a cancer to develop.

Epidemiology

A study in

Sweden Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is the Kingdom of SwedenUNGEGN World Geographical Names, Sweden./ref> is a Nordic country located on ...

showed that 21.5% of smokers and 3% of nonsmokers (genetic pigmentation or unknown cause) had lesions that could be classified as an oral melanin pigmentation. A gingival melanin index in 4 degrees was established. Already with a consumption of 1-3 cigarettes a day 9.3% of all 20.333 examined showed a smoker's melanosis. Pipe smokers had smoker's melanosis in 16.8%. One year after the start of cigarette smoking a clinically visible smoker's melanosis could be seen in 12.3% of women, and 17% among men. In cigarette smokers who quit smoking, the number of individuals with smoker's melanosis becomes slowly less frequent after 2–3 months, but can still be seen in a few former smokers three years after smoking stop. Although clinically visible genetic melanin pigmentations in the mouth are present in several ethnic groups all over the world, more mucosal areas will be melanin-pigmentet if tobacco products are used. Smoker's melanosis is found in India,Sridharan S, Ganiger K, Satyanarayana A, Rahul A, Shetty S: Effect of environmental tobacco smoke from smoker parents on gingival pigmentation in children and young adults: a cross-sectional study. J Periodontol 2011; 82:956-962.Hedin CA, Pindborg JJ, Daftary DK, Mehta FS: Melanin depigmentation of the palatal mucosa in reverse smokers. J Oral Pathol Med 1992; 21:440 444. Italy, Japan, Nigeria, Sweden, Turkey, USA, and several other countries.Hedin CA, Axéll T: Oral melanin pigmentation in 467 Thai and Malaysian people with special emphasis on smoker's melanosis. J Oral Pathol Med 1991; 20:8-12. Smoker's melanosis is expected to be found also in other tissue surfaces exposed to tobacco and tobacco smoke, for instance lips and in skin of the fingers holding the cigarette. Future studies will also show if the use of tobacco exaggerates the pigmentation of skin.

Gallery

Discoloration of skin on finger holding cigarette.jpg, Possible smoker's melanosis. Discoloured skin on finger. Area close to cigarette glow. Melanocyte with melanin in dendrite to the left.jpg, Melanocyte with melanin granules in dendrite. Melanocytes with dendrites. Smoker´s melanosis.jpg, Melanocytes in basal cells of a smoker's gum. Melanosomes in the most basal part of gingival epithelium.jpg, Melanin granules in the basal epithelium under light microscope Smoker´s melanosis.jpg, Smoker's melanosis in upper and lower gums.

References

External links