Four patients presented with asymptomatic gray-white oral mucosal tissues that sloughed and peeled away leaving a normal tissue base. This peeling phenomenon appeared unlike any known oral mucosal disease, although it somewhat resembled leukoedema and chemically irritated oral mucosa due to certain dentifrices and mouthwashes. Examination of biopsy tissue from three of the four cases along with stripped tissue from the fourth case revealed an intraepithelial cleft near the surface of each specimen. The linear cleft ran parallel to the epithelial surface. Foci of adjacent cells displayed intracellular edema, a feature commonly noted in leukoedema. There was evidence of neither acantholysis nor inflammation. The microscopic pattern was unlike the mucosal entities pemphigus vulgaris, mucosal pemphigoid, lichen planus, candidiasis, and mucosal biting. Although the authors questioned the patients in detail regarding all forms of mechanical and chemical trauma, including those from certain dentifrices and mouthwashes, they could not detect causative factors for these lesions.