Head & Neck

Dental and Oral Side Effects

Head and neck cancer is treated with surgery, radiation therapy, drug therapy and other medications. Used alone or in combination, these treatments can result in side effects that range from minor to severe. Because treatment to the head and neck can affect breathing, speaking, eating, swallowing and other vital functions, it is critical to know the side effects to expect and how to prevent them from making these functions even more challenging. 

Before Treatment

Some complications can be prevented by seeking dental care before treatment. The goal is to treat any existing problems so they do not become worse during treatment. This may include having some teeth extracted.

Find a dentist who specializes in treating people who have oral complications from cancer treatment.

After Treatment Begins

Check your mouth daily. Many problems can be seen or felt. The sooner you notice them, the quicker they can be managed.

Following are some common dental and oral side effects. Some can be attributed to specific treatments (see Table 1).

Dry mouth , or xerostomia (zeer-oh-STOH-mee-uh), occurs when the salivary glands do not produce enough saliva because of damage from radiation therapy, chemotherapy or other medications. This is uncomfortable and increases your risk of both oral infections and tooth decay.

Infections are a greater risk for many reasons related to cancer treatments, including damage to mouth tissues, a lower white blood cell count (neutropenia) and a weakened immune system. These therapies, as well as steroids and antibiotics, can also alter the balance of bacteria in your mouth, making you susceptible to a fungal infection commonly called thrush. Confirm the symptoms that require a call to the doctor.

Jaw and/or mouth stiffness can be caused by surgery, radiation therapy or even stress. Often painful, it can interfere with healing and lead to malnutrition. Prevention is very important because the condition is difficult to treat. Ask your health care team about jaw muscle exercises, such as opening your mouth as far as possible without pain, then closing it to repeat. Medication may be used to relax your jaw and mouth muscles.

Mouth pain and soreness can make eating, chewing and swallowing difficult, preventing you from getting adequate nutrition. Pain can also slow the healing process. Controlling mouth pain is essential to the success of your treatment as well as your quality of life.

Oral mucositis (myoo-koh-SY-tis), or mouth sores, can occur when mucous membranes become inflamed. This is common with chemotherapy and is also possible with radiation therapy. Tiny sores begin in the mouth lining and become red, burn-like or ulcer-like sores. They can make it difficult to eat, drink or swallow.

Swallowing difficulties , called dysphagia (diz-FAY-jee-uh), and painful swallowing can make getting adequate nutrition a real challenge. Your health care team will examine you to determine the underlying cause, which could be related to treatment or to the cancer itself. You will likely be referred to a speech therapist to learn techniques that will help make swallowing easier. Drinking thickened fluids may also help. Call your doctor right away if you cough or choke while eating.

Taste changes are common for people receiving radiation therapy to the head or neck because cells in the salivary glands and/or taste buds can become damaged. Your sense of smell may also be affected. The condition generally lessens within a few months after treatment ends.

Tooth decay and gum disease are likely to occur. It is important to find a dentist experienced in treating cancer survivors. Discuss how frequently you should schedule routine dental visits from now on.


Table 1 - Oral side effects by treatment type

Treatment Type Side Effects
Chemotherapy Bleeding, dehydration, dry mouth, infection, inflammation, malnutrition, oral mucositis, pain and soreness, swallowing difficulties, taste changes
Radiation therapy (in the area where the radiation beams are aimed) Breakdown of bone or tissue, dehydration, dry mouth, growth of fibrous tissue or muscle, gum disease, infection, inflamed mucous membranes, jaw and mouth stiffness, malnutrition, oral mucositis, pain and soreness, swallowing difficulties, taste changes, tooth decay
Surgery Infection, jaw and mouth stiffness, pain and soreness, swallowing difficulties

Practical Tips for a Healthy Mouth

Connect with other head and neck cancer survivors to learn how they manage dental and oral side effects. These suggestions may also help.

  1. Find a dentist who is experienced with treating head and neck cancer patients, and schedule regular visits.
  2. Brush your teeth, tongue and gums with a soft-bristled toothbrush using a fluoride toothpaste every four hours and at bedtime. 
  3. Use unscented lip balm to keep your lips from drying and cracking. Avoid oil-based products.
  4. Wear dentures that fit properly, and leave them out whenever possible to expose your gums to air. Brush and rinse dentures every day.
  5. Avoid spicy, acidic, crunchy and sugary foods.
  6. Sip water often and keep a water bottle with you.
  7. Use alcohol-free mouthwash to avoid irritating your mouth lining.
  8. Floss daily, unless bleeding occurs. 
  9. Rinse your mouth several times a day and after eating with a mixture of 1 tablespoon of baking soda in 1 quart of warm water.
  10. Avoid alcohol and tobacco products.