Causes of TMD

The temporomandibular joints are among the most utilized joints in the body, due to their prolonged use during chewing, talking, singing, yawning, etc. Jaw dysfunction (TM dysfunction) means that the lower jaw is not in its proper relationship to the upper jaw. This frequently results in a dislocation of the protective disc anteriorly as the lower jaw assumes a position further back than normal.

Condyles too Far Back: The Main Cause of TMD

The temporomandibular joint is affected like no other joint in the body. Behind the condyle (top of lower jaw), there are several structures that affect the health of the jaw joint itself. One is the posterior ligament which acts as a rubber band to pull the disc backward during closing of the jaw. Like all joints, the TM joints contain a large amount of nerves and blood vessels that on a subconscious level give the brain information about the position and condition of the joint. When the jaw is closed, the disc, which has no feeling, acts as a shock absorber to prevent the nerves and blood vessels from being compressed. When the mouth opens and the condyle and the disc move forward, the blood vessels expand to fill the vacated space. When the condyle is pushed too far backwards in the joint, it can slip off the cartilage disc and into these nerves and blood vessels. When nerves and blood vessels are compressed, the whole structure is unbalanced, affecting the nerves, the ligaments and the muscles of the head, neck and face. This dislocated jaw causes pain and other symptoms, which affect health and a person's quality of life.


Normal Joint

Dislocated Jaw Joint
Disc Displaced Anteriorly


Dislocated Jaw Joint, Disc Displacement Anteriorly

The treatment of choice for a patient with a dislocated jaw due to the lower jaw (condyle) being positioned too far back would be to use a lower splint, orthotic or functional jaw orthopedic appliance to reposition the lower jaw forward.

Unbalanced Muscles

Unbalanced muscles can be a result of clenching or grinding of the teeth. If a muscle is overworked or becomes fatigued due to a structural imbalance, other muscles must compensate. This compensation causes the body to adjust to an abnormal postural state. Compensation means the body adapts to a state that is unhealthy. The body will start to experience symptoms on a mild level, such as occasional headaches. Slowly the symptoms start to occur on a more frequent level until eventually you are experiencing pain on a daily basis.

Whether you have a slightly displaced disc, a dislocated disc, unfavorable head posture or body posture, the abnormal forces and strain produced by tired, spastic muscles can refer pain into the neck, face or head. These muscle tension headaches can be so severe that they are confused with migraine headaches. Unfortunately, patients are often not examined for TMJ disorder and the "migraine" treatment works poorly.

The treatment for patients with migraine headaches is often the prescribing of pain medications such as Imitrex. This medication is ineffective in solving problems relating to dislocated jaw joints (TM dysfunction). Patients are advised to contact a dentist who utilizes appliances designed to reposition the lower jaw forward or to control parafunctional habits to try and solve the problem as early as it is diagnosed.

Trauma to the Head and Jaw

A severe blow to the head or the jaw can cause the disc to be dislocated due to the force of the impact on the jaw. Patients may experience swelling, limited opening and clicking in the joint. Patients with this acute injury should seek emergency treatment immediately to avoid further damage to the joint.