Chemotherapy and radiotherapy patients - Dental care

Chemotherapy and your mouth

Chemotherapy treatment can affect your mouth in different ways. You may experience mouth ulcers, mouth infections, loss of taste or a dry mouth.

Mouth ulceration (mucositis)

During chemotherapy the lining of the mouth may become thin and ulcerated. You may find eating and swallowing more difficult.


Infections can occur in the mouth because of a weakened immune system. It’s important to maintain good oral hygiene during chemotherapy to help reduce infections.

Before chemotherapy

Start good oral care habits at home before treatment begins. Your mouth should be as healthy as possible before chemotherapy starts.

During chemotherapy

Most dental treatment should be avoided during chemotherapy. Emergency treatment is possible if your immune system is strong enough.

Use a very soft toothbrush during chemotherapy. If you need to stop brushing, a chlorhexidine-based mouthwash will help keep your teeth clean

Radiotherapy and your mouth

Radiotherapy can affect white blood cells, skin cells and the lining of your mouth. These effects are often temporary but can persist. Problems occurring after radiotherapy depend on where the radiation is applied, how often the treatment is given and how much radiation is used.

Dry mouth

Saliva lubricates the mouth and assists speech, taste and chewing. Saliva washes teeth providing minerals for repair. Saliva also helps prevent bacteria, viruses and fungi from causing infections, tooth decay and gum disease.

Radiation applied in the area of the salivary glands (below and in front of the ears and under the chin) can affect the amount and quality of saliva. This can be a permanent side effect of radiotherapy.

Sometimes saliva becomes thick and ropey, making swallowing difficult. This usually improves after radiotherapy is completed.

Whether the mouth is dry or has thick saliva, you need to take special care to protect teeth from losing enamel. Sipping water or using gels and lubricants can help moisten your mouth.

Mouth ulceration (mucositis)

Ulceration and inflammation of the lining of the mouth occurs in areas that are directly affected by radiation. Tissues become red, swollen and painful ulcers may develop. Wearing dentures may be uncomfortable

Ulcers usually heal after treatment has finished. Mouthwashes and gels may help to reduce your discomfort.

Loss of taste

Radiation can affect your taste buds. You may experience loss of taste. Radiation treatment applied to the head and neck area can affect the number of taste buds remaining at the completion of treatment.

Using chlorhexidine mouthwash is recommended during oncology treatment. Mouthwash can change the surface of the tongue and alter taste. Taste often recovers once cancer treatment is complete.


This is a severe complication that can occur following radiotherapy and affects the bones ability to heal. Tooth extraction following radiotherapy can make the condition worse. For this reason, dental work should be completed before starting radiotherapy.

Before radiotherapy 

Patients about to start radiotherapy are required to have a dental check-up. This helps identify any teeth and areas of the mouth that might cause problems. Any teeth that are severely decayed or loose should be removed before radiotherapy starts.

Start good oral care habits at home before radiotherapy begins.

During radiotherapy

It’s important to have regular dental checks to monitor your oral health. Care may include: 

  • anaesthetic gels and mouth rinses
  • medication to relieve pain
  • frequent sips of water 
  • sucking on ice 
  • antibiotic or antiseptic mouth rinses

Chemotherapy and radiotherapy 

After treatment care

It’s important to maintain good oral health at home.

Follow these simple steps to keep your teeth and gums healthy:

  • gently brush your teeth and gums in the morning and before bed at night
  • use a small, soft toothbrush and a pea-sized amount of fluoride toothpaste
  • spit the toothpaste out, but don’t rinse
  • gently clean between your teeth with floss -your dentist can show you how
  • limit how often you have sugary food and drinks 
  • chew sugar-free gum – it stimulates saliva flow and neutralises acids in your mouth 
  • have regular dental visits 
  • use fluoride gels – your dentist may suggest applying a small amount of fluoride gel to your teeth once a day on a toothbrush or in a specially made tray for extra protection 
  • use Tooth Mousse – Tooth Mousse helps protect teeth from rapid enamel loss and helps your mouth feel moist. Your dentist will give advice on availability.

Caution:products containing fluoride (such as gels and fluoride rinses) should not be swallowed and must be kept out of reach of children.