Jaw Mobility

Trismus can be divided into two types: one where the soft tissues or muscles are damaged and one where the bones or joints are affected. There are many possible causes of this condition, one being related to head and neck cancer. Head and neck cancers are commonly treated with surgery, radiation or a combination of the two, which can lead to complications such as limited jaw mobility (trismus). Thankfully, there are ways to prevent and treat trismus.

About your jaw

The jaw is the combination of the lower (mandible) and upper (maxilla) jaw bones, that form the mouth. Along with the teeth, the jaw is typically used for chewing and consuming food.

About trismus

Trismus is a condition where you can experience limited jaw mobility after surgery and radiation treatment. It causes pain, interferes with eating and speaking, and can negatively affect quality of life. These difficulties can occur at a time when proper nutrition and oral hygiene are important for recovery.

Preventing and managing trismus

Developing trismus can be a result of head and neck cancer, or a complication of surgery and radiation treatment. Thankfully, there is a system available to you. To help to prevent the onset of trismus or to treat the condition, we recommend the use of TheraBite Jaw Motion Rehabilitation System.

TheraBite Jaw Motion Rehabilitation System

TheraBite is designed to restore jaw mobility and is clinically proven to deliver results. It is portable and utilizes repetitive passive motion to stretch the tissue, strengthen weakened muscles and mobilize joints.


Passive motion and jaw stretching exercises with TheraBite are clinically proven to be an effective form of jaw therapy. The most commonly used treatment programs are*:

  • The 5-5-30 Protocol: 5 times per day, 5 stretches, 30 seconds followed by a 30 second pause
  • The 7-7-7 Protocol: 7 seconds followed by a 7 second pause, 7 stretches, 7 times per day

Curious to learn more about how TheraBite can help you and your jaw mobility? Please contact us for more information.

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*You must see your physician, clinician, or qualified caregiver for advice on your condition and on products that may be appropriate for you. Always read the Instructions for use before starting to use any of the products. For Instructions for use, please visit www.atosmedical.com


    Beekhuis GJ, Harringon EB. Trismus. Etiology and management of inability to open the mouth. Laryngoscope. 1965;75:1234-58.

    Cardoso RC, Kamal M, Zaveri J et al. Self-reporsted trismus: prevalence , severity and impact on quality of life in oropharyngeal cancer surviviorship: a cross sectional survey report from a comprehensive cancer center. Support Care Cancer . 2021 Apr;29(4):1825-1835.

    Hammerlid E, Silander E, Hornestam L, Sullivan M. Health-related quality of life three years after diagnosis of head and neck cancer--a longitudinal study. Head Neck. 2001;23(2):113-25.

    Horst RW. Trismus: its causes, effects and treatment. ORL Head Neck Nurs. 1994;12(2):11-2.

    Kraaijenga S, van der Molen L, van TH, Hilgers F, Smeele L. Treatment of myogenic temporomandibular disorder: a prospective randomized clinical trial, comparing a mechanical stretching device (TheraBite(R)) with standard physical therapy exercise. Cranio. 2014;32(3):208-16.

    Montalvo, C., et al., Impact of exercise with TheraBite device on trismus and health-related quality of life: A prospective study. Ear Nose Throat J, 2017. 96(1): p. E1-E6.

    Nordgren M, Abendstein H, Jannert M, Boysen M, Ahlner-Elmqvist M, Silander E, et al. Health-related quality of life five years after diagnosis of laryngeal carcinoma. Int J Radiat Oncol Biol Phys. 2003;56(5):1333-43.

    Pauli N, Andrell P, Johansson M, Fagerberg-Mohlin B, Finizia C. Treating trismus: A prospective study on effect and compliance to jaw exercise therapy in head and neck cancer. Head Neck. 2015;37(12):1738-44.

    Scott B, Butterworth C, Lowe D, Rogers SN. Factors associated with restricted mouth opening and its relationship to health-related quality of life in patients attending a Maxillofacial Oncology clinic. Oral Oncol. 2008;44(5):430-8.

    Senthilkumar S, Tarun S. A study on effectiveness of therabite exercises to improve the jaw range of motion in trismus among oral cancer patients. Research Journal of Pharmacy and Technology. 2020;13(2):4.

    van der Molen L, van Rossum MA, Burkhead LM, Smeele LE, Rasch CR, Hilgers FJ. A randomized preventive rehabilitation trial in advanced head and neck cancer patients treated with chemoradiotherapy: feasibility, compliance, and short-term effects. Dysphagia. 2011;26(2):155-70.


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