Oral Frictional Hyperkeratosis Differential Diagnoses

Updated: Feb 19, 2021
  • Author: Jose Luis Tapia, DDS; Chief Editor: Jeff Burgess, DDS, MSD  more...
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Diagnostic Considerations

Several conditions should be included in the differential diagnosis of frictional keratosis in both children and adults. [21, 22, 23] Occasionally, plaquelike lesions of lichen planus and lupus erythematosus may resemble areas of frictional keratosis. Chemical burns and acute pseudomembranous candidiasis may have the same clinical appearance as frictional keratosis; however, these white areas can be easily wiped off with gauze because they consist of necrotic epithelium (in the case of superficial chemical burns) or fungal colonies (in the case of acute pseudomembranous candidiasis). Sheets or clustered aggregates of Fordyce granules and scars may resemble frictional keratosis because of their yellowish-white, submucosal appearance. In these examples, the surface mucosa is smooth.

Consider genokeratosis, such as white sponge nevus, hereditary benign intraepithelial dyskeratosis, and pachyonychia congenita, when the lesions are multifocal. These 3 autosomal dominant conditions appear in young persons. In white sponge nevus, the hyperkeratinization is restricted to the oral cavity, the esophagus, the anus, and the vagina. In hereditary benign intraepithelial dyskeratosis, gelatinous plaques manifest in the ocular conjunctiva. In pachyonychia congenita, the fingernails exhibit subungual hyperkeratosis.

White patches associated with smoking and smokeless tobacco can be clinically indistinguishable from frictional keratosis. Clinical information regarding tobacco and smokeless tobacco use is essential for differentiating these conditions. Some examples of tobacco-related keratoses are caused by thermal and chemical irritation, while other keratotic lesions represent a precancerous entity. For this reason, differentiating between lesions from smoking or smokeless tobacco and frictional keratosis is important because their prognoses may be different from that associated with frictional keratosis, which has an excellent prognosis. Also see Smokeless Tobacco Lesions.

An uncommon but important adherent white lesion typically found on the lateral border of the tongue is hairy leukoplakia. This shaggy white plaque is caused by the Epstein-Barr virus infection and is associated with immunosuppression resulting from HIV infection. Similarly, the long-term use of topical steroids to treat chronic ulcerative conditions (ie, mucous membrane pemphigoid, erosive lichen planus) may result in the formation of white patches on the lateral borders of the tongue that are indistinguishable from hairy leukoplakia.

Leukoplakia is a clinical term reserved for white lesions that cannot be characterized clinically or pathologically as any other disease (ie, frictional keratosis, lichen planus, candidiasis, hairy leukoplakia, white sponge nevus). Leukoplakia may be associated with premalignant or malignant epithelial changes.

Contact stomatitis associated with the use of artificially flavored cinnamon products (eg, gum, candy, toothpaste, mouthwashes, dental floss) may present as a white patch that may resemble frictional keratosis. However, pain and burning are common symptoms in contact stomatitis. [24]

Differential Diagnoses