Hello, I’m Evelyn and I’m a qualified dentist and have experience working in Oral and Maxillofacial Surgery.

Mouth problems are a common result of head and neck cancer or its treatment. Getting support from a dental professional from early in the process can really help to minimise discomfort and improve your quality of life. 

Dental care should be provided in conjunction with your oncology team, as unfortunately, increased susceptibility to dental disease can be life-long after head and neck cancer. 

Before treatment – get a specialist assessment

If you’ve been diagnosed with head and neck cancer, you should be referred to a specialist clinic for a full dental assessment before treatment starts. This clinic should continue seeing you during and after treatment.

They should give you a full oral assessment, ideally at least a month before starting treatment. This should to give you adequate time to heal if you need any dental treatment. 

Toothbrushes in mug

At the assessment, your dentist should:

  • Identify and treat any existing dental disease
  • Assess your risk of developing dental disease in the future
  • Advise you on good oral hygiene and how to prevent dental disease
  • Give diet advice
  • Smooth sharp edges of teeth or fillings to prevent trauma to the mouth lining
  • Assess and adjust your dentures, if you wear them. You may be advised to remove your dentures during your therapy, or minimise the time you wear them to avoid discomfort.

You should also keep attending your local dentist as they will be able to offer support as well. You should tell the dentist about your diagnosis, what medications you are taking and your proposed treatment dates. 

During treatment: Good oral hygiene tips

Invasive dental treatment should be avoided if possible during cancer treatment, but if treatment is required your dentist will consider how this is best delivered. A dental professional should support you to maintain a high standard of oral hygiene. 

  • They may advise you to use alcohol-free chlorhexidine mouthwash
  • Brush with a soft toothbrush if possible
  • If you experience discomfort when brushing, then you can soak gauze or small sponges in chlorhexidine mouthwash or water and use them to clean inside the mouth, but make sure you resume normal tooth brushing as soon as you can
  • Patients at risk of aspiration should sit upright and have suction available during cleaning
  • Avoid foods, drinks and mouthwashes that irritate your mouth.  Chlorhexidine mouthwash can be diluted with water 1:1 if it causes discomfort
  • Avoid: hard foods, spicy foods, strongly-flavoured toothpastes, alcohol (especially spirits), smoking, fizzy drinks, acidic fruit, and fruit drinks -  these can contribute to side effects and damage the teeth and mouth lining

Common side effects

  • Mucositis – acute inflammation of the mucosa (lining of the mouth) which may occur following radiotherapy or chemotherapy. It can cause the mucosa to become uncomfortable, red and sometimes ulcerated (typically healing 2-3 weeks after treatment)
  • Dry mouth (xerostomia) – saliva becomes thick and viscous. This can be a permanent side effect
  • Infections – commonly thrush (candida). This is usually seen as a white coating or white plaques inside the mouth – antifungal medicine will be provided if this is detected
  • Loss of appetite and altered taste (during treatment)
  • Jaw stiffness (trismus) can also be long lasting 

After treatment

You should carry on having regular check-ups with a dental professional after treatment. This will allow support for the management of side effects and to pick up any dental disease and provide treatment if required. 

If you had radiotherapy in this area, then you will remain at high risk of dental decay afterwards. Your dentist will advise on prevention strategies suitable for you which may include:

  • Using high fluoride concentrated toothpaste or mouthwashes. Fluoride mouthwash can be used once daily at a different time from tooth brushing
  • Regular application of fluoride varnish to minimise tooth decay. This can be done by your dentist up to twice per year
  • Rinsing dentures after meals, and cleaning them at least once daily by brushing with a toothbrush. It is advisable to do this over a basin filled with water to prevent damage if dropped. The dentures should be soaked in either chlorhexidine mouthwash or dilute sodium hypochlorite solution (Milton) overnight, provided there are no metal components. Dentures should always be removed at night


After radiotherapy to the jaws, the blood supply to the bone is reduced. This may lead to parts of the jaw bone dying. This is known as osteoradionecrosis (ORN). 

Symptoms include pain, swelling, numbness, loose teeth, a discharge or a break in the lining of the mouth (mucosa). If you develop any of these symptoms it’s important to seek advice from your doctor or dentist.

To reduce your risk of developing ORN:

  • Stop smoking, or cut down
  • Make sure dentures fit correctly
  • See your dentist regularly
  • Maintain an excellent standard of oral hygiene (assisted by a dental professional)
  • If a dental extraction becomes necessary, please seek advice as precautions are necessary and you will usually be treated by a specialist 

Coping with a dry mouth

Dry mouth (xerostomia) can happen during treatment with some types of chemotherapy, but usually returns to normal at the end of treatment. Dry mouth post-radiotherapy tends to be longer-lasting and problematic. 

There are a few different methods that can help – it’s a good idea to try different ones and see which works for you. 

  • Medication,
  • Chewing gum
  • Frequent sips of water
  • Gels
  • Pastilles (only for edentulous patients as they are acidic and cause damage and sensitivity to the teeth)
  • Acupuncture 

Caring for your mouth is an essential part of your head and neck cancer therapy. Keeping your mouth clean and healthy will make things more comfortable and help to make your cancer journey a little bit easier. 

If you have any concerns a member of your oncology team will be more than happy to give you some advice.

Read more on this blog.

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