A reaction pattern in the oral mucosa characterized by epithelial desquamation, vesiculobullous lesions, erythema, and/or erosions of the gingiva. Desquamative gingivitis is not a specific diagnosis. The differential diagnosis is broad, ranging from irritant dermatitis, foreign body gingivitis, and allergic reactions, to autoinflammatory conditions, to autoimmune bullous diseases. Patients frequently experience intense discomfort and may have difficulty eating and drinking. Lesions typically arise along the buccal aspect of the gingiva, most commonly in a diffuse pattern. However, lesions may occur at any site along the gingiva. The patient may develop extra-oral involvement in other sites.