Trismus (Mouth is stiff and hard to open)

Sometimes radiation therapy to the head and neck can cause your mouth to become very stiff and hard to open. This condition is called trismus.

Fortunately, there are exercises that you can do to help maintain your mouth opening. This is important because trismus can make it difficult for you to eat, talk and take care of your teeth and gums.

These exercises are designed to increase range of motion in your jaw. You should do the exercises 5 times during each day:

  • Open and close your mouth, stretching as far as possible. Repeat 10 times.
  • Place your middle and index fingers on your lower front teeth and using a twisting motion with your fingers, pry your mouth open. Hold it open as wide as possible for 2 seconds. Relax. Repeat 10 times using each hand. **this can also be done using mouth props**
  • Hold your mouth open for a count of 30 using a mouth prop. Repeat 5 times.
  • Place the heel of both hands under your chin and push up. At the same time, try to open your mouth against the force of your hands pushing up. Repeat 10 times.

** You can make mouth props by stacking several tongue blades together – adding more blades to the stack as your mouth can stretch farther.