A study looking at using exercises before radiotherapy to help reduce mouth opening problems in head and neck cancer patients (Open Wide)

Cancer type:

Head and neck cancers
Mouth (oral) cancer
Nasal and paranasal sinus cancer
Nasopharyngeal cancer
Pharyngeal cancer
Salivary gland cancer





This study tried to find out whether using a mouth exercise programme before radiotherapy for head and neck cancer reduced the risk of mouth opening problems. 

More about this trial

Doctors can use radiotherapy or chemoradiation Open a glossary item to treat head and neck cancer. If the radiotherapy is directed at the jaw joint, or the muscles surrounding this, the treatment could cause damage and scarring.
This can lead to problems opening your mouth properly (trismus Open a glossary item). If jaw movement becomes limited it can cause difficulties with chewing and swallowing and keeping your mouth clean.
People who develop trismus after their treatment are often shown how to do exercises to gently open and stretch the jaw. One way to do this is with the Therabite device. You hold the handle of this device in your hand and the other part between your teeth. You squeeze the handle for a few seconds, then release it. This gently moves the jaw joint and stretches the muscles.
Researchers thought that these exercises might be useful for people to do before they start treatment. The aims of this study were to find out:
  • if patients would use the Therabite during and after their radiotherapy
  • whether exercise before treatment reduced problems with mouth opening

Summary of results

The study team found that the mouth exercise programme using Therabite was acceptable by patients to use before and after radiotherapy but not during.
This study was open to people in the Royal Glamorgan Hospital, Wales between July 2014 and March 2015.
The results have been presented as a poster at several conferences.  
About this study
11 people joined this study. 
The people taking part were to use the mouth exercise programme with Therabite every day for 6 months. This began before starting radiotherapy, continued during radiotherapy and for a period after finishing radiotherapy.
Mouth opening measurements were taken before starting radiotherapy and then every month for 6 months. 
  • before treatment 
  • then at 3 months
  • 6 months
At the end of the study the team did an informal ‘exit interview’. Patients were asked about their thoughts and feelings about:
  • being in the study
  • doing the mouth exercise programme
  • using Therabite  
Everyone found it acceptable to do the mouth exercise programme using Therabite before starting radiotherapy. And everyone was able to fully complete the programme every day. 
During radiotherapy this acceptance fell to a third of the people (33%). And no one was able to fully complete the programme every day. The reasons for this included:
  • tiredness (fatigue) 
  • pain 
  • other side effects caused by the radiotherapy
After radiotherapy everyone said it was acceptable to continue with the mouth exercise programme. And everyone was able to fully complete the programme every day. 
Mouth opening
How far people were able to open their moths did increase after 1 month of starting the programme. 
It dropped again during radiotherapy due to the impact of treatment and its side effects. 
And started to rise again after radiotherapy. By 6 months after treatment people were able to open their mouth nearly as far as they could before treatment started.
Quality of life
The researchers found there wasn’t a big difference in their quality of life before, during and after doing the mouth exercise programme. 
The study team concluded that patients didn’t find the mouth exercise programme using Therabite fully acceptable during their radiotherapy. This was due to the side effects of radiotherapy. 
They did say that starting the programme before treatment does appear to help with mouth opening. And that increasing how far patients can open their mouth before treatment gives them more ability to cope with the side effects of treatment. 
The team also said this study showed it was possible to do a larger randomised clinical trial. This would contribute to the information they already have. And help answer the question ‘whether using the mouth exercise programme with Therabite does help with moth opening problems caused by radiotherapy’. 
As a result of this study the Royal Glamorgan Hospital has changed how they treat people with head and neck cancer. And these changes are to be rolled out across South Wales.  
Where this information comes from
We have based this summary on information from the research team. The information they sent us has been reviewed by independent specialists (peer reviewed Open a glossary item) but may not have been published in a medical journal.  The figures we quote above were provided by the research team. We have not analysed the data ourselves.

Recruitment start:

Recruitment end:

How to join a clinical trial

Please note: In order to join a trial you will need to discuss it with your doctor, unless otherwise specified.

Please note - unless we state otherwise in the summary, you need to talk to your doctor about joining a trial.

Chief Investigator

Ms Menna Payne

Supported by

Cam Taf Univeristy Hospital Health Board
Tenovus Innovation Grant 

If you have questions about the trial please contact our cancer information nurses

Freephone 0808 800 4040

Last review date

CRUK internal database number:


Please note - unless we state otherwise in the summary, you need to talk to your doctor about joining a trial.

Around 1 in 5 people take part in clinical trials

3 phases of trials

Around 1 in 5 people diagnosed with cancer in the UK take part in a clinical trial.

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