TMJ disorders can be associated with locking of the jaw. Essentially what happens is the mechanics of the jaw’s movements are out of line. The jaw bone, the mandible, has a round “ball” that fits into a shallow cavity of the skull bone just in front of the ear. This area is called the temporal bone. If the jaw joint is out of line, the “ball” can become displaced out of the shallow cavity, and the jaw becomes “locked”. When this happens in TMJ, sometimes the person has to move their jaw to one side so it will move back into place and relax.
In TMJ disorders, the misalignment of the jaw joint can cause pain and inflammation to occur. This pain is most commonly in the jaw, but other areas of the face, head and neck can be involved. In some cases, the inflammation associated with TMJ syndrome can cause changes to the temporo-mandibular joint that make the jaw fall out of alignment. A locking jaw therefore can be a cause of TMJ or it can be a result of having TMJ. Either way, it suggests poor alignment and secondarily poor movement of the jaw.
Popping or clicking noises can also be associated with a locking jaw, as can pain with jaw movement. However, sometimes these other symptoms are absent. A locking jaw without any other TMJ symptoms may just indicate jaw deformities in position. Even though in this situation TMJ cannot be diagnosed because of the lack of other complaints, the poor mechanics of the jaw are a risk for subsequently developing TMJ disorders. For this reason, realignment of the jaw is still encouraged.
Other TMJ Symptoms: