Cancer Treatments & Oral Health

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Most people are aware of common side effects of cancer treatment like nausea and hair loss. But many don't realize that most people treated for cancer develop problems in the mouth. These problems can make it hard to eat, talk, and swallow. This may interfere with cancer treatment and lessen quality of life. This information will explain how you can prevent or manage these side effects.

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Head and neck radiation and chemotherapy can cause mouth problems that range from dry mouth to life-threatening infections. These problems can occur when receiving treatment or even months or years after treatment.

For example, mouth sores can occur because chemotherapy and radiation kill fast-growing cells including both cancer cells and healthy cells that are fast-growing, like the cells that line your mouth. In addition, radiation to the head and neck can damage the glands that make saliva (the salivary glands), greatly reducing the amount of saliva that’s produced. Without enough saliva, tooth decay and other infections can develop.

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Head and neck radiation may cause:

  • Dry mouth.
  • Severe tooth decay.
  • Loss of taste or changes in the way food tastes.
  • Sore mouth and gums.
  • Infections.
  • Jaw stiffness.
  • Limited mouth opening.
  • Jawbone changes.

Chemotherapy may cause:

  • Dry mouth.
  • Painful mouth and gums.
  • Oral bleeding.
  • Change in taste.
  • Burning, peeling, or swollen tongue.
  • Infection.
  • Mouth ulcers.
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Treatment for oral side effects of cancer treatment will depend on which mouth problems you develop. For example, treatment for jaw stiffness or pain might consist of daily jaw exercises. Treatment for oral mucositis, which results in painful mouth sores, might require a medication to coat the lining of your mouth to protect it when you eat and/or a topical medication to numb the pain.

Be sure to follow all directions from your doctor or dentist about treating your mouth problems.

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Helpful Tips

If you are a cancer patient, here are some things you can do to reduce the risk and impact of treatment-related mouth problems:

  • See a dentist about 1 month before beginning cancer treatment to make sure your mouth is healthy.
  • Give your dentist your cancer doctor’s contact information. It’s important they talk to each other about your cancer treatment.
  • Take good care of your mouth during and after treatment. Follow the dentist’s instructions for how to keep your mouth clean.
  • Keep your mouth moist by drinking lots of water, sucking ice chips, and using sugar free gum or candy. Artificial saliva may also be necessary.
  • Avoid foods and drinks that could irritate your mouth such as sharp, crunchy foods or hot, spicy foods.
  • Avoid tobacco products and alcoholic beverages.
  • Call your healthcare provider if your mouth hurts.

If you receive radiation to the head and neck area, you should also:

  • Talk to your dentist about using fluoride gel to help prevent tooth decay.
  • Exercise the jaw muscles three times a day: open and close the mouth as far as possible (without causing pain) 20 times. This helps prevent jaw stiffness.
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Additional Resource

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Cancer Treatments & Oral Health Research from NIDCR

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Last Reviewed
March 2024