Jaw pain used to always be blamed on the temporomandibular joint (TMJ), the hinge like connection that allows the lower part of the jaw to move up and down to open your mouth. It was thought this needed to be ‘fixed’ to get rid of the pain and the focus was on your bite (malocclusion). However now we look at the jaw more holistically which is why we use the term Temporomandibular Disorders (TMD), looking at multiple sources of jaw and facial pain from dental problems, migraine or anxiety and stress.
The TMJ is cleverly designed, the mandible (lower part of the jaw) is a horseshoe shape which fits into the two notches in the temporal bones. These notches allows the mandible to rotate so it hinges open as you open your mouth. The ends of the mandible (condyles) are wrapped in tough layers of fibrous cartilage that withstand shearing forces and then ligaments hold everything in place. We also have a small disc in between the mandible and temporal bone which acts a shock absorber.
We have a large number of muscle groups that have to carefully coordinate by contracting and relaxing at the right times. A very important muscle is the masseter muscles, a thick band that connects the mandible to the cheekbone on both sides of the face. It’s really important for chewing and is actually one of the strongest muscles in the body (pound for pound).
Classic TMD pain symptoms:
Jaw muscle stiffness
Limited movement or locking of the jaw
Radiating pain: side of the head, face and neck
Crepitus (crackling, grinding sound) – however research has shown that sounds such as clicking or clunking do not mean there is a serious problem. Jaw noises are common and do not indicate in isolation a jaw disorder or need ‘fixing’.