Leukoplakia

Nature 
Leukoplakia means literally "white plaque," and is commonly found anywhere in the mouth -- on the gums, inside the cheek, on or under the tongue, on the roof of the mouth, or below the lips. Such growths arise from chronic irritation. They may also occur on other mucous membranes, [eg] of the genitalia and cervix.
Broader 
Type 
(G) Very specific problems