The temporomandibular joint (TMJ) is located in the face where the temporal bone (cheek bone) and the mandible (jaw bone) meet, often simply referred to as the jaw.
We have a TMJ on each side of the face and these can sometimes become sources of pain. When this occurs it is often referred to as ‘TMD’ or temporomandibular joint dysfunction. This is a catch all term which includes both intra-articular (joint and disc) and extra-articular (usually muscle, but also ligament and tendon) sources of pain.
TMD can be treated with many different physiotherapy techniques including manual therapy, electrotherapy, exercise and medical acupuncture (sometimes referred to as dry needling).
Most clinicians would agree that medical acupuncture is most effective when the muscles which act on the jaw are the primary problem causing pain and dysfunction. However, clinically I have found when the muscular environment in which the jaw functions is treated and normalised with a medical acupuncture approach, other potential pain sources such as the joint itself can improve.
As such, let’s consider two of the muscles which are most likely to be involved with TMD.
- The deep lateral pterygoid muscle opens the jaw and mouth, as well as producing a sideways movement of the jaw away from the side of the acting muscle. As such, a dysfunctional lateral pterygoid muscle could limit opening of the mouth, as well cause the jaw to shift or deviate awkwardly to one side when opening the mouth. Sometime this can result in pain or a clicking feeling or noise coming from the jaw, usually on one side. A method of treating this dysfunction is direct needling the lateral pterygoid muscle. This has to be done carefully by a trained and experienced physiotherapist given the depth of the muscle. A study of 48 people reported statistically significant differences up to 70 days post needling of the lateral pterygoid muscle in terms of reduced pain intensity and improved mouth movements (Gonzalez-Perez et al., 2015).
- The more superficial masseter muscle helps the jaw to close as it shortens and aids opening as it lengthens. Along with the lateral pterygoid, this muscle can also be a source of pain as well as upsetting normal movements of the jaw. More often that not, both have to be treated together to achieve a good treatment result. A study by Fernandez-Carnero et al., (2010) concluded that needling of the masseter muscle improved pain levels as well as how wide the jaw was able to open. A larger study (52 subjects) investigated the dry needling effects on myofascial (another term for mainly muscular) jaw pain (Diracoglu et al., 2012). They also found positive results in terms of relieving pain and muscle tenderness. (Diracoglu et al., 2012). Itoh et al., (2012) studied trigger point (tender, taut portions of muscle) acupuncture in a large variety of muscles associated with TMD (masseter, lateral pterygoid, temporalis, digastric, sternocleidomastoid, trapezius and splenius capitis) with results showing reduced pain intensity among chronic TMD sufferers.
In addition, electro-acupuncture (the use of a gentle electrical current to enhance the effects of needling) has been shown to produce anti-nociceptive (pain-relieving) and anti-inflammatory effects when used to treat TMD (Gondim et al., 2012). Clinically, I find the use of supplemental electro-acupuncture very effective for certain patients.
In summary, it would seem the literature is supportive of the use of medical acupuncture/dry needling in the treatment of TMJ related pain and dysfunction otherwise known as TMD; particularly when there is a significant muscular component to the pain. As with most areas of physiotherapy, further highly rigorous trials are required with larger sample sizes including longer-term follow-up.
As a physiotherapist who has treated many cases of TMD integrating medical acupuncture, my view is that this technique is highly effective, well received by my patients, and leads to quicker outcomes. Given an evidence based approach should consider not just the supporting research, but also clinical experience and patient preference for certain types of treatment, I feel confident in continuing to offer medical acupuncture as part of an integrated approach to TMD alongside other physiotherapy techniques.
By Rachel Neary BSc. (Physio), MISCP
Chartered Physiotherapist
References
Image courtesy of author zitona qatar from doha, qatar, ref. wikipedia
- Diracoglu, D., Vural, M., Karan, A. and Aksoy, C. (2012) 'Effectiveness of dry needling for the treatment of temporomandibular myofascial pain: a double-blind, randomized, placebo controlled study', J Back Musculoskelet Rehabil, 25(4), pp. 285-90.
- Fernández-Carnero, J., La Touche, R., Ortega-Santiago, R., Galan-del-Rio, F., Pesquera, J., Ge, H. Y. and Fernandez-de-Las-Penas, C. (2010) 'Short-term effects of dry needling of active myofascial trigger points in the masseter muscle in patients with temporomandibular disorders', J Orofac Pain, 24(1), pp. 106-12.
- Gondim, D. V., Araujo, J. C., Cavalcante, A. L., Havt, A., Quetz Jda, S., Brito, G. A., Ribeiro Rde, A. and Lima Vale, M. (2012) 'CB1 and CB2 contribute to antinociceptive and anti-inflammatory effects of electroacupuncture on experimental arthritis of the rat temporomandibular joint', Can J Physiol Pharmacol, 90(11), pp. 1479-89.
- Gonzalez-Perez, L. M., Infante-Cossio, P., Granados-Nunez, M., Urresti-López, F. J., Lopez-Martos, R. and Ruiz-Canela-Mendez, P. (2015) 'Deep dry needling of trigger points located in the lateral pterygoid muscle: Efficacy and safety of treatment for management of myofascial pain and temporomandibular dysfunction', Med Oral Patol Oral Cir Bucal, 20(3), pp. e326-33.
- Itoh, K., Asai, S., Ohyabu, H., Imai, K. and Kitakoji, H. (2012) 'Effects of trigger point acupuncture treatment on temporomandibular disorders: a preliminary randomized clinical trial', J Acupunct Meridian Stud, 5(2), pp. 57-62.