With leukoplakia (loo-koh-PLAY-key-uh), thickened, white patches form on your gums, the insides of your cheeks, the bottom of your mouth and, sometimes, your tongue. These patches can't be scraped off.

Doctors don't know what causes leukoplakia but consider tobacco — whether smoked, dipped or chewed — to be the main culprit in its development.

Leukoplakia usually isn't dangerous, but it can sometimes be serious. Although most leukoplakia patches are noncancerous (benign), some show early signs of cancer. Many cancers on the floor of the mouth — beneath the tongue — occur next to areas of leukoplakia. For that reason, it's best to see your dentist if you have unusual, persistent changes in your mouth.

Symptoms Causes Risk factors Complications Prevention

Leukoplakia can have various appearances. Changes usually occur on your gums, the insides of your cheeks, the bottom of your mouth and, sometimes, your tongue.

Leukoplakia may appear:

  • White or grayish in patches that can't be wiped away
  • Irregular or flat-textured
  • Thickened or hardened in areas
  • Along with raised, red lesions (erythroplakia), which are more likely to show precancerous changes

A type of leukoplakia called hairy leukoplakia primarily affects people whose immune systems have been weakened by medications or disease, especially HIV/AIDS. Hairy leukoplakia causes fuzzy, white patches that resemble folds or ridges on the sides of your tongue. It's often mistaken for oral thrush — an infection marked by creamy white patches, which can be wiped away, on the area that extends from the back of your throat to the top of your esophagus (pharynx) and the insides of the cheeks. Oral thrush also is common in people with HIV/AIDS.

When to see a doctor

Sometimes mouth sores can be annoying or painful without being harmful. But in other cases, mouth problems can indicate a more serious condition.

See your dentist if you have any of the following:

  • White plaques or sores in your mouth that don't heal on their own within two weeks
  • Lumps or white, red or dark patches in your mouth
  • Persistent changes in the tissues of your mouth

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