Note: As a new practitioner I thought it would be fun to incorporate the things I am currently learning about into educational content that can be of benefit to other practitioners and their patients. I am by no means an expert on these topics, so if you encounter any information you disagree with, please don’t hesitate to contact me and I’ll edit it.
Introduction to the Temporomandibular Joint
Whether you’re chewing a piece of gum, or gabbing on the phone with a friend – your temporomandibular joint (TMJ) is one of the most frequently used joints in your body. With that much use, wear and tear is common. Today we’ll be explaining what the joint is, common pathologies of the TMJ as well as ways Acupuncture can help in the treatment of TMJ disorders.
“The temporomandibular joint is a combined hinge and plane joint formed by the condylar process of the mandible and the mandibular fossa and articular process of the temporal bone. The temporomandibular joint is the only freely movable joint between skull bones” (Tortora, 2012). The joint is separated into an upper and lower cavity, each filled with synovial fluid. Between the condylar process of the mandible, and the mandibular fossa sits an articular disc. This articular disc is what divides the joint into an upper and lower cavity. It ensures that the condylar process moves smoothly out of the mandibular fossa, and along the articular tubercle as the jaw opens.
Apart from the mandible, and the articular disc, there are the muscles of mastication (literally, your ‘chewing muscles’). These are the main muscles involved in moving the mandible (jaw) around. These include the:
Masseter: this muscle elevates the mandible (jaw) and closes the mouth
Lateral Pterygoid: this muscle primarily pulls the head of the condyle out of the mandibular fossa along the articular tubercle (to protrude the jaw), also assists in depressing the mandible (along with the digastric, mylohyoid, and geniohyoid)
Medial Pterygoid: Assists in elevation of the mandible, minor contribution to protrusion of the jaw, as well as excursion of the mandible.
Temporalis: this muscle elevates and retracts the mandible, pulling it posteriorly.
Now that we’ve been introduced to the main components of a healthy, properly functioning temporomandibular joint, we can move onto looking at disorders of the joint.
Temporomandibular Joint Disorders
There are a wide array of things that can lead to disorders, and pain of the jaw. Disorders of the joint itself, tension in the surrounding muscles, even arthritis, can all lead to pain and abnormal functioning of the temporomandibular joint. While Acupuncture can help to manage pain in most of these cases, it is better suited to the treatment of some pathologies more than others – and depending on the severity of the disorder, surgery is sometimes the only option. TMJ disorders can be narrowed down to four main causes:
- Myofascial pain syndrome – This pathology is due to dysfunction, or tension of the muscles that control jaw movement. Symptoms often include highly sensitive trigger points on the muscles of mastication that, when pressed, will refer pain to the jaw, or other areas of the head/neck. Clenching or grinding of the teeth, headaches and abnormalities in jaw mobility (Porter, 2011). Acupuncture is most effective in cases of myofascial related TMJ pain, due to it’s ability to release trigger points, and relax tense muscles.
- Internal derangement of the joint – this can be congenital, or due to overuse, external trauma etc. If internal derangement of the joint affects the articular disc (displacing it either anteriorly, or posteriorly) then pain, clicking, popping, or even locking of the jaw may result. Facial asymmetry may be visible in severe cases. Pain due to internal derangement tends to be more localized to the temporomandibular joint. Depending on the severity, Acupuncture can be of help in pain management, but surgery may be required.
- Osteoarthritis of the joint – Osteoarthritis of the temporomandibular joint is a degenerative disease that can have an effect on the articular cartilage, bones, or synovial tissue of the joint. Acupuncture can assist in reducing inflammation, and pain – but obviously won’t have much effect on structural changes in the jaw. Acupuncture is best employed when OA of the jaw is detected early.
- Temporal arteritis – This generally doesn’t occur in patients under the age of 50. It is a more serious condition leading to inflammation or irritation of the temporal arteries, which supply blood to the head. It is often accompanied by symptoms that the other causes are not – like double vision, weakness, weight loss, throbbing in the temples etc. Temporal arteritis is serious, and can lead to stroke or blindness – therefore I do not advise using Acupuncture as a stand alone treatment. Only receive acupuncture treatment for Temporal arteritis if you’ve been cleared by a physician.
These are some of the most common causes, but the causes of TMJ related pain often aren’t clear. Regardless of the cause, common symptoms of TMJ disorders are:
- Pain or tenderness around the jaw
- Clicking or popping of the joint
- Difficulty or pain while chewing, yawning etc.
- Pain around the ear
- Stiffness of the neck, temples, or shoulders
- Locking of the jaw
- Grinding or clenching of the teeth (often while asleep)
If you are suffering from any of these symptoms it is best to consult with your doctor, or dentist, in addition to your Acupuncturist.
What can Acupuncture do to help?
Acupuncture can be used to reduce inflammation in the joint, relax tense muscles, ease pain of the affected area, as well as help modulate any abnormal activity of the nerves in the face/neck. In terms of Chinese Medical Theory, most of the Yang Meridians have some effect on the jaw.
While Acupuncture is an effective modality on its own, the best results occur when needling is combined with manual manipulation / release of the temporomandibular joint, and surrounding masticatory musculature. In my own practice, I generally encourage patients to seek treatment from a massage therapist, or physiotherapist who has experience in intraoral massage, in addition to their acupuncturist.
Below are a list of points commonly used to treat TMJ dysfunction, as well their function and location.
Common Points Used:
|Stomach 7||At the lower border of the zygomatic arch, in the depression anterior to the condyloid process of the mandible.||Needling this point goes directly into the lateral pterygoid muscle. One of the most frequently used points in the treatment of TMJ pain.|
|San Jiao 21, Small Intestine 19, Gall Bladder 2||These three points are located in a vertical line, anterior to the tragus of the ear, and posterior to the condyloid process of the mandible.||Given their close proximity to the ear, these points are useful if pain radiates from the jaw into the ear area.|
|Extra Point: Taiyang||At a point midway, and slightly posterior to the lateral eyebrow, and the outer canthus of the eye.||This point targets the anterior fibres of the temporalis muscle. Especially useful if headaches or trigger points in the temple region accompany the TMJ dysfunction.|
|Large Intestine 18||On the lateral side of the neck, between the two heads of the SCM muscle, in line with the laryngeal prominence.||Given it’s location overtop of the SCM muscle, this point can be used if neck tension is leading to jaw pain.|
|Large Intestine 4||Between the thumb and forefinger, at the midpoint of the second metacarpal bone, and close to its radial border.
If you squeeze the thumb and index finger together, this point sits at the highest point on the bulge of muscle.
|This is the command point of the face. It is a commonly used distal point in the treatment of jaw pain, headache, or toothache. It is generally needled on the side opposite to the pain.|
|Stomach 6||Approximately 1 fingerbreadth anterior and superior to the angle of the jaw at the prominence of the masseter muscle.||This point sits directly over the belly of the masseter muscle. Especially useful if grinding/clenching of the teeth is a symptom.|
I hope you enjoyed this overview of Acupuncture’s role in the treatment of TMJ dysfunction. If you have any questions please don’t hesitate to contact me.
If you are currently living in Edmonton, Alberta #YEG and would like to book an appointment with me (Jon McDonell) please visit the Meridian Health Centre website, call (780)-428-8897, or email me at firstname.lastname@example.org !
Deadman, P., Khafaji, M. A., & Baker, K. (2011). A manual of acupuncture. Hove: Journal of Chinese Medicine Publications.
Magee, D. J. (2014). Orthopedic Physical Assessment. Saint Louis: Elsevier Health Sciences.
Porter, R. S., Kaplan, J. L., & Merck Sharp & Dohme. (2011). The Merck manual of diagnosis and therapy. Whitehouse Station, N.J: Merck Sharp & Dohme Corp.
Tortora, G. J., & Nielsen, M. T. (2012). Principles of human anatomy. New York: Wiley.