Aphthous stomatitis caused by a reduction in numbers of CD4+ T cells may be implicated in RAS-type ulceration in HIV infection. The thickness of the mucosa may be an important factor in aphthous stomatitis. Usually, ulcers form on the thinner, non-keratinizing mucosal surfaces in the mouth. Factors which decrease the thickness of the mucosa increase the frequency of occurrence, and factors which increase the thickness of the mucosa correlate with decreased ulceration. The nutritional deficiencies associated with aphthous stomatitis (Vitamin B12, folate, and iron) can all cause a decrease in the thickness of the oral mucosa (atrophy). Local trauma is also associated
Stomatitis necrotizing ulcerative gingivitis, or a more severe form (also termed necrotizing stomatitis). The term "necrotizing gingivostomatitis" is also sometimes used. Also called smoker's palatal keratosis, this condition may occur in smokers, especially pipe smokers. The palate appears dry and cracked, and white from keratosis. The minor salivary glands appear as small, red and swollen bumps. It is not a premalignant condition, and the appearance reverses if the smoking is stopped. Chronic ulcerative stomatitis is a recently discovered condition with specific immunopathologic features. It is characterized by erosions and ulcerations which relapse and remit. Lesions are located on the buccal mucosa