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Dental and Oral Complications

Side effects of cancer treatment may cause a variety of problems affecting the mouth, teeth and jaw, and they impact your quality of life. The side effects you experience will depend on the type and duration of the treatment you receive. There are things you can do to decrease the risk of dental and oral problems.

A thorough oral evaluation by a dental professional is recommended prior to treatment. During and after treatment, work closely with your entire healthcare team to manage any oral complications. Proper dental hygiene on an ongoing basis is essential.

How Treatment Affects Oral (Mouth) Health

Chemotherapy. Most of the oral complications caused by chemotherapy are short term and typically resolve after treatment ends. Oral complications caused by chemotherapy include:

  • Mouth sores (oral mucositis)
  • Bleeding in the mouth
    • Low platelet count causes bleeding problems. 
  • Dry mouth (xerostomia)
  • Tooth decay and gum disease
  • Infection
    • Low white blood cell count increase the risk of infection. 
  • Pain
  • Difficulty swallowing (dysphagia)
  • Taste changes (dysgeusia)
  • Nerve damage (neurotoxicity)
  • Changes in dental growth and development in children
  • Malnutrition or dehydration

Radiation to the head and neck. Common oral complications from radiation therapy include: 

  • Mouth sores
  • Salivary gland dysfunction, which causes decreased saliva production. This can lead to:
    • Dry mouth
    • Difficulty swallowing
    • Taste changes
    • Speech problems
    • Yeast infection (in the mouth or throat)
  • Tooth decay and gum disease 
  • Pain
  • Nerve damage 
  • Changes in dental growth and development in children 
  • Malnutrition or dehydration
  • Difficulty opening the mouth (trismus), also known as lockjaw
  • Fibrosis (thickening and scarring of tissue)
  • Osteoradionecrosis
    • A rare condition in which the loss of blood flow to bone cells in the jaw causes the cells to break down, die and expose bone. 

Stem cell transplant. The high doses of chemotherapy typically used before a stem cell transplant may cause dental and oral side effects. Patients who receive an allogeneic stem cell transplant (with cells from a donor) have an increased risk of graft-versus-host disease (GVHD). GVHD occurs when transplanted donor cells attack the patient’s body.

Oral complications of chronic GVHD can include: 

  • Inflammation, thinning and ulceration of oral mucosal tissues. There may be redness and “lacy” white patches in the mouth. This can resemble lichen planus, an itchy rash causing burning or soreness.
  • Salivary gland dysfunction, which causes decreased saliva production. This can lead to:
    • Dry mouth
    • Difficulty chewing or swallowing
    • Taste changes
    • Tooth decay
  • Difficulty opening the mouth (trismus), also known as lockjaw

Targeted therapy. Targeted therapy uses drugs or other substances to identify and attack specific types of cancer cells, generally with less harm to normal cells. However, some targeted therapies can have negative side effects that affect the mouth by causing mucositis, infection or salivary gland dysfunction. Tyrosine kinase inhibitors are one type of targeted therapy.

Immunotherapy. Immunotherapy utilizes your own immune system to fight cancer, and generally results in fewer short-term side effects than chemotherapy. Common effects of immunotherapy on the mouth include mucositis, taste changes and salivary gland dysfunction. There are different types of immunotherapy, including immune checkpoint inhibitors and chimeric antigen receptor (CAR) T-cell therapies.

Bone-modifying drugs. Bisphosphonates are a class of drugs that prevent bone loss. They are often prescribed to patients with myeloma (cancer of the plasma cells) because myeloma can dissolve, weaken and even break bones. Bisphosphonates can help bones stay strong by slowing down this destructive process. Common bisphosphonates for treating bone problems in people with myeloma are pamidronate (Aredia®) and zoledronic acid (Zometa®). Patients should understand that although bisphosphonates are effective, these drugs can also cause risk to their dental health.

Denosumab (Prolia® or Xgeva®) may also be prescribed to reduce the risk of fractures in people with myeloma or certain other cancers that have spread to the bones. Denosumab is a monoclonal antibody (a type of protein made in the laboratory) that binds to a protein called RANKL on the surface of certain bone cells. It keeps bone from breaking down and prevents cancer cells from growing.

Bisphosphonate treatment or denosumab can both cause a rare but serious side effect called “osteonecrosis of the jaw” or “ONJ.” ONJ causes part of the jaw bone to die, which can lead to pain, open sores and higher risk of tooth loss and infection. Patients should have a dental check-up before starting treatment with bisphosphonates or denosumab, and address any dental problems before treatment begins.

For information about the drugs listed on this page, visit Drug Listings.

Before Cancer Treatment 

Good dental hygiene, before and during cancer treatment, may help to either prevent or decrease the associated oral complications. Patients should learn about proper dental care so that they can lessen side effects and manage symptoms. The goal is to treat existing oral problems before treatment begins and to become educated about the potential risks, side effects and complications of therapy. 

When treatment is not urgent, patients should visit a dentist at least four weeks before treatment starts. A pretreatment oral evaluation will identify problems such as cavities, fractured teeth, loose crowns or fillings, or gum disease. These problems should all be addressed in order to reduce the risk of complications. During the pretreatment evaluation, discuss potential oral complications caused by cancer treatment and ways to prevent and manage them. 

During Cancer Treatment

To decrease the risk of complications such as cavities, mouth sores and infections during treatment, it is important to keep the mouth, teeth and gums clean.

Patients can take the following steps to help improve their oral health:

  • Brush teeth and gums two to three times a day.
  • Use a fluoride toothpaste with a mild taste—flavorings can irritate the mouth.
  • Gently floss once a day.
  • Rinse the mouth frequently (every 4-6 hours) with a solution of water, salt and baking soda, to prevent soreness.
  • Use an alcohol-free antibacterial rinse two to four times a day to prevent gum disease.
  • Use a lip-care product to prevent your lips from drying and cracking.
  • Brush dentures every day, clean with a denture cleaner recommended by the dentist, and keep dentures moist when not being worn.
  • Pay attention to diet. Try to:
    • Choose healthy foods that are mild, soft, and easy to chew and swallow.
    • Avoid hot, spicy, highly acidic and crunchy foods that may irritate your mouth.
    • Avoid sugary foods, like candy or soda, that can cause cavities.
    • Avoid alcohol and tobacco products.
  • Keep your mouth moist during cancer treatments so that you are more likely to avoid mouth sores. You can
    • Drink a lot of water.
    • Suck on ice chips to prevent dryness.
    • Use sugarless gum or hard candy.
    • Use a saliva substitute.
  • Ask about fluoride treatments that may be recommended to prevent cavities or tooth sensitivity.
  • Talk with your doctor about ways to improve bone health with vitamin D and/or calcium supplements.
  • Practice oral stretching exercises on a daily basis if you’re undergoing radiation treatment for head and neck cancer (to avoid problems opening and closing your mouth).
  • Look in your mouth every day and note sores or other changes. Take steps to help prevent and treat a sore mouth.

Management of Complications

Contact a member of your healthcare team if you notice oral complications. The patient, doctor and dentist should work together to manage symptoms and treat complications with medication and/or supportive care. Supportive care can include pain management, nutritional advice, counseling, complementary therapies and more.

  • Mouth rinses: Mouth rinses that contain baking soda and salt, over-the-counter rinses, or prescription rinses may soothe sore spots in the mouth.
  • Pain medications: Pain medications, including some narcotics, may be used to relieve mouth pain. 
  • Antibiotics: Antibiotics, antiviral drugs, or antifungal drugs are used to treat infections.
  • Other prescription medications: Oral gels and medications that will increase saliva may be prescribed.

After Cancer Treatment

When cancer treatment has finished, it is important to:

  • Visit your dentist as soon as appropriate after completing your treatment.
  • Treat any dental issues that may arise.
  • Maintain optimal oral health and dental care for life.

Financial Implications

Paying for dental care is a concern for many cancer patients. Not everyone can afford dental insurance, and dental benefits are not always an option. It is important that patients educate themselves about their medical and dental insurance coverage and its limitations before they begin cancer treatments. 

Patients should share their financial concerns with their medical and dental teams and find out if there are any financial resources available to them. See the fact sheet, Dental and Oral Complications of Cancer Treatment Facts, for a list of organizations that may be able to help. 

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