Exercise Therapy Research on Tempromandibular Disorder

Exercise Therapy Research on Tempromandibular Disorder
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Take Home Points on TMD
  1. Exercise therapy is an effective initial treatment of TMD.
  2. A combination of muscle length, strength, and timing is likely an effective rehabilitation program for TMD.

    Tempromandibular disorder (TMD) is a broad term encompassing any clinical problems associated with the tempromandibular joint. This includes injuries to the joint, muscles, or ligaments. Most often patients have pain, joint sounds, limited range of motion, headaches, and/or dizziness. It is most prevalent in females aged 20 – 45 years (Carlsson 2006). 

    TMD has no specific cause in many cases and the risk factors are broad, ranging from traumatic, anatomical, to psychological causes. Often times conservative treatment is the first course of action, as the symptoms are often muscular (Greene 2001; Dworkin 2002; Michelotti 2004; Michelotti 2005; Clark 2008). Physical therapists are movement and muscular specialist and one the main aides in improving TMD. Unfortunately, the research on physical therapy treatments is scattered, as various exercises and manual therapies are performed in different trials. Luckily, exercise and manual therapy are effective, but finding the most effective manual and exercise therapy is necessary (Michelotti 2004; Magnusson 1999). A recent study by Moreas (2013) reviewed the whole body of exercise based TMD treatments and made the following recommendations based on different types of exercise.

    Stretching — Muscle Length

    Stretching is often prescribed when the desired range of motion is restricted. Stretching can be static (not moving) or dynamic (moving). Often times dynamic stretching is effective, simply by repeated opening and closing the mouth, while keeping your tongue at the roof of your mouth, similar to repeatedly saying the letter “N”. 

    Coordination Exercise — Muscle Timing

    Opening the jaw is a complicated movement, as it requires two joints to move in coordination (the right and left side). Uncoordinated jaw movements often results in jaw pain and joint sounds (Marbach 1996). 

    Improving the coordination of the jaw is often helpful and as easy as watching one open and close the mouth in the mirror, while attempting to keep the midline of the lower dental arch parallel to the mirror. This can also be done by having your fingers at the TMJ and feeling both joints move together.

    Strengthening — Muscle Strength

    Most jaw exercises are performed isometrically, as adding resistance through a range of motion is difficult. I guess you could put a dumbbell in your mouth, but I question this safety. Isometric exercises promote muscular contraction without the occurrence of joint motion.

    For the jaw, the hand can be used to provided a counter-resistant force, keeping the jaw stationary during contraction. These types of exercises can be done in all the planes of motion, improving strength of various muscles.

    Conclusion

    These forms of exercises are only one part of the TMD equation. Often times, improving the tone of the muscle (another muscle length) technique is needed with manual therapy to the muscle and fascia. Sometimes, decreasing stress and improving relaxation is necessary, to prevent clenching and overuse of certain muscles. Coordination with a dentist is also required in most scenarios, as night-splinting may prevent over use during sleep. 

    References:
    1. Moraes AR, Sanches ML, Ribeiro EC, Guimarães AS. Therapeutic exercises for the control of temporomandibular disorders. Dental Press J Orthod. 2013 Sept-Oct;18(5):134-139.
    2. Carlsson GE, Magnusson T, Guimarães AS. Tratamento das disfunções temporomandibulares na clínica odontológica. São Paulo: Quintessence; 2006. p. 9-23.
    3. Greene CS. The etiology of temporomandibular disorders: Implications for treatment. J Orofac Pain. 2001;15(2):93-116. 
    4. Dworkin SF, Turner JA, Mancl L, Wilson L, Massoth D, Huggins KH, et al. A randomized clinical trial of a tailored comprehensive care treatment program for temporomandibular disorder. J Orofac Pain. 2002;16(4):259-76.
    5. Michelotti A, Steenks MH, Farella M, Parisini F, Cimino R, Martina R. The additional value of a home physical therapy regimen versus patient education only for the treatment of myofascial pain of the jaw muscles: short-term results of a randomized clinical Trial. J Orofac Pain. 2004;18(2):114-25.
    6. Michelotti A, De Wijer A, Steenks M, Farella M. Home exercises regimes for the management of non-specific temporomandibular disorders. J Oral Rehabil. 2005;32(11):779-85.
    7. Clark GT. Classification, causation and treatment of masticatory myogenous pain and dysfunction. Oral Maxillofac Surg Clin North Am. 2008;20:145-57
    8. Magnusson T, Syrén M. Therapeutic jaw exercises and interocclusal appliance therapy. Swed Dent J. 1999;23(1):27-37.
    9. Marbach JJ. Temporomandibular pain and dysfunction syndrome. History, physical examination,and treatment. Rheum Dis Clin North Am. 1996;22(3):477-98.

     Dr. John, DPT, CSCS