Cancer treatment often takes a team of health professionals—oncologists, nurses, surgeons, radiologists, pathologists, and social workers—to coordinate and provide support for patients. Dentists are increasingly being considered an important part of the cancer care team.

People with cancer can experience unique issues related to their oral health:

 - Radiation to the head and neck can damage the salivary glands, hurting their ability to produce saliva, which can lead to tooth decay or cavities

- Radiation and chemotherapy can also cause painful mouth sores

- Patients with cancer that has spread to their bones, or who are undergoing treatment that can weaken their bones, may be prescribed high doses of antiresorptive medications such as bisphosphonates. These medications can cause a rare condition called osteonecrosis of the jaw, in which the jawbone is exposed through the gums. 

- Other treatments—including chemotherapy and bone marrow transplants—lower the immune system leaving patients susceptible to infection. Infections in the mouth during cancer treatment are especially dangerous, given the immune system's inability to fight back.

An abscessed tooth may mean having to stop chemotherapy to treat the infection.  Fortunately, intervening early to eliminate infection can minimise complications during the course of therapy.

What cancer patients can do to keep their mouths healthy

Keeping up your oral hygiene before, during, and after cancer treatment is critical.  They recommend that people diagnosed with cancer take the following steps to protect their oral health:

• Visit a dentist before you begin cancer treatment for an exam, X-rays, and cleaning. The dentist may check for infections in your mouth, which can complicate cancer care that lowers your immune system. If your dentist finds an infection, they can treat it prior to your cancer treatment. 
• If you'll be receiving radiation for cancer of the head or neck, a custom mouth guard to wear during radiation treatments is an option. A mouth guard can protect areas of your mouth from unnecessary radiation, and may be particularly useful for those with metal fillings and crowns. You may also benefit from jaw exercises or a referral to a physical therapist. 
• Keep up your oral hygiene during cancer treatment.  We recommend that you continue brushing your teeth, although you may want to switch to a very soft toothbrush. You may also need to take a break from alcohol-based mouthwash if you develop mouth sores.
• Stay hydrated, especially if you are experiencing dry mouth.