The Temporomandibular Joint (TMJ), commonly known as “Jaw joint”, is one of the most complex synovial joints in the body. Temporomandibular disorders – TMD - refer to any conditions caused by associated muscles or the TMJ itself. Classified as a compound joint, the TMJ is formed by 3 articulating parts: The condylar process of the mandible, the mandibular fossa with the articular tubercle (eminence) of the temporal bone and the intra-articular disc, which divides the joint into an upper and lower compartment. The fibrocartilagenous structure of the disc acts as a shock absorber and its biconcave shape allows smooth jaw movements. The TMJ is the only moveable joint of the skull and allows rotational and translational (sliding) movements, so as to open your mouth for speech and ingestion as well as for food mastication or facial expressions. Thereby, the joint ligaments restrict and prevent excessive jaw movements. TMD, which are more prevalent among women and show a great psychosocial component, fall, according to the NIDCR, into three main categories:
Myofascial pain syndrome
Myofascial pain, described as one of the most common TMD, can provoke symptoms such as headaches, tooth and earaches amongst others. “Myo”, derived from the Greek word “muscle” and “fascial”, meaning the connective tissue surrounding muscles and linking them to other body tissues. Fascia, providing a great tensile strength but high flexibility, binds and supports organs, bones, nerves and blood vessels, so as to create a continuous web interpenetrating the body. This is from utmost importance, because pains can be referred and linked from one part to another part of the body, which is the characteristic of myofascial pain. Tense and sensitive knots, so called “Trigger points” form, commonly in the strong masticatory muscles and elicit radiating pain patterns. Therefore, trigger points, found in one or multiple of the associated muscles, can lead to:
- headaches and migraines, which usually affect the forehead and/or temples
- tight and aching jaw muscles, especially if pressure is applied
- locked jaws or restricted movements
- earaches and tinnitus symptoms (ringing in the ear)
- sinusitis symptoms, such as nasal congestion and/or facial pressure above and below the eyes
- decreased ROM (Range of Motion)
In order to treat and release those masticatory muscles effectively, an oral treatment should be provided, so as to reach the deeper and intrinsic muscles of the TMJ. The associated muscles and structures, moreover, need to be assessed and accordingly released, stretched, mobilized or strengthened. Thereby, the upper cervical joints with their suboccipital muscles are very important in contributing to cervical stability, TMJ function, fine tuning of the head, orientation and balance.
Internal derangements of the TMJ
If the articular disc is deformed or degenerated as through bruxism (Grinding) or clenching of the teeth, it loses its physiological biconcave shape which will lead, in most cases, to an “anteromedial” (forward-centered) slip of the disc. However, the exact cause for (painful) disc displacement is controversial, having its peak incidence during puberty. Nonetheless, contributing risk factors exist, which can lead over time to microtraumas of the TMJ’s, such as:
- hyperactivity of the masticatory muscles (esp. lateral pterygoids) as through bruxism
- severe malocclusions (bad bite)
- joint hypermobility and excessive jaw movements
- altered (degenerated) articular disc
Macrotraumas that can elicit an internal disc slip are acute injuries such as:
- whiplash syndromes
- strong blow to the mandible
An anterior displacement with reduction is very common and can be heard as a clicking or popping noise during mouth opening and/or closure. If the condition isn’t painful and the mouth can be fully opened, treatment isn’t necessarily required. However, over time, the rear capsule and ligaments are being strained causing inflammation, tenderness and pain. In cases of anterior displacement without reduction, the disc is misaligned and/or deformed obstructing condylar movements. In an attempt to open the mouth, the discal ligaments and retrodiscal tissue, which is highly innervated and vascular are strained, leading to a very painful condition of “Lockjaw”.
If internal derangements persist, the disc, due to its lack of blood vessels, might degenerate, tear or perforate. Grinding sounds during jaw movements are a very common sign.
Osteoarthritis, as the most common articular disease worldwide, can affect any joint in the body and is the most common type of arthritis seen in the TMJ.
Osteoarthritis is defined by:
- inflammatory/degenerative articular cartilage break down
- decrease in joint space
- bony changes such as bone spurs (osteophytes), subchondral sclerosis (Hardening of the bone ends below the articular cartilage) and subchondral cysts (fluid-filled sacs)
Though unknown etiology, age-related changes in cartilage density and resilience as well as wear and tear of the joint precede the development of osteoarthritis. Secondary causes or risk factors include traumas, such as an acute blow to the mandible, chronic teeth grinding or clenching, especially at night, which produces the greatest force on teeth and TMJ, hypermobile TMJs or rheumatoid arthritis.
Typical symptoms, if present, include TMJ pain during jaw movements, tenderness to touch and crepitus (grating sounds during movements). Limited ability to open the mouth with deviation to the affected side, clicking sounds, and/or temporary locking of the jaw can be observed.
Osteoarthritis typically occurs on one side, whereas rheumatoid arthritis is often seen symmetrically. Rheumatoid arthritis, in contrast to osteoarthritis, is a chronic inflammatory autoimmune disease, affecting the synovium (lubricous lining) of multiple joints as well as extraarticular tissues such as lungs, heart or blood vessels. The TMJs are most often one of the last joints involved. Articular joint damage increases as the disease progresses and can lead, in severe cases, to ankylosis (fusion of the TMJ) with an open bite.
Osteopathic treatment approach for TMD:
For a holistic, osteopathic treatment, it is important to not solely consider the TMJ, but all related structures, muscles and tissues. Therefore, an initial consultation and examination is imperative to determine any present and future treatments!
Initially, a detailed consultation is important to highlight:
- traumatic injuries to the TMJ, such as whiplash syndromes or blows to the mandible
- chronic bruxism and clenching (during the day or at night?)
- oral splints (What kind, where positioned and when worn?)
- inflammatory/degenerative disorders such as Osteoarthrtis or Rheumatoid Arthritis
- additional signs and symptoms such as vertigo, tinnitus, sinusitis and nausea
- habits such as gum chewing, fingernail biting, cheek or tongue biting/chewing contributing to increased masticatory muscle activity
- sleep deprivation and especially STRESS
This information in accordance with the physical examination contributes to and defines subsequent treatment sessions. During the examination I observe, measure or palpate respectively:
- posture, especially head (and jaw) position in relation to the neck, shoulders and body
- spinal curvatures/discrepancies such as scoliosis
- ROM (Range of Motion) of the TMJ as well as the cervico-thoracic spine, possibly shoulder joints
- deviations during mouth opening as well as clicking, popping or grating sounds which either lead to the assumption of an internal derangement with disc displacement or degenerative changes such as Osteoarthritis
- differences in muscle tonicity between both sides and possible hyper- or hypotonia
Depending on the results of the examination, the treatment can vary. However, I like to involve the patient actively in the treatment by letting her/him perform goal oriented head, shoulder, or jaw movements while I’m working on the muscle, fascia or joint. By this means, muscular stabilization is gained during mobilization (through the active component of the movements) and fast and long lasting results can be accomplished. I prefer to start treating on the according shoulder, neck, or throat (supra and infrahyoid muscles) area, before I utilize oral techniques. Oral treatments are important to reach deep situated muscles, such as the lateral and medial pterygoids or the deep layer of the masseter muscle. After releasing tension in masticatory muscles, a local TMJ treatment involving traction therapy (for pain relief, gain in joint space, allowing disc repositioning) and joint mobilization increasing ROM are fitting, always under the consideration/comparison of both sides.
Besides all the techniques, it is important to raise and practice awareness in daily situations such as job site and to break habits like constant gum chewing or teeth clenching in stressed situations. Additionally, taking up good posture, especially aligning the head above neck and shoulders (rather than in a forward position), strengthens the suboccipital muscles and reduces shoulder and neck tension. Stability in this cranio-cervical area, dura mater flexibility and TMD are closely related. Therefore, I like to perform and prescribe exercise for this often neglected site.
Please feel free to come in for an initial treatment or contact me by e-mail: firstname.lastname@example.org for further guidance.
To book an osteopathic treatment with Silva Schoenherr call: 604-733-7744 or book online.