Oral inflammation and ulcers, known as stomatitis, may be mild
and localized or severe and widespread.
They are invariably painful. Stomatitis may involve swelling and redness of the oral mucosa or discrete, painful ulcers (single or multiple). Less commonly, whitish lesions form, and, rarely, the mouth appears normal (burning mouth syndrome) despite significant symptoms. Symptoms hinder eating, sometimes leading to dehydration and malnutrition. Secondary infection occasionally occurs. Some conditions are recurrent.
Stomatitis may be caused by local infection, systemic disease, a physical or chemical irritant, or an allergic reaction Approach to Dental and Oral Symptoms: Some Causes of Stomatitis many cases are idiopathic. Because the normal flow of saliva protects the mucosa against many insults, xerostomia predisposes the mouth to stomatitis of any cause