Disc slippage in the jaw involves forward displacement of the disc that acts as a cushion between the skull and the lower jaw. In the early stages, the anteriorly displaced disc returns to its normal position as the mouth opens, accompanied by a clicking or popping sound. This is called “reduced anterior displacement”. In later stages, when the disc is displaced forward, the condylars act as a barrier to movement and limit mouth opening. This is called “reductionless anterior displacement”. It is also referred to as a “closed lock”.
What Causes Dislocated Discs?
There are two main causes of tooth displacement. The most common cause is lower jaw trauma. Depending on the amount of trauma, there may be anterior disc displacement with or without reduction. The other reason is the change in the friction properties of the joint due to the chronic habit of clenching and grinding (bruxism) or degenerative changes in the joint surfaces due to arthritis.
Who Gets Dislocated Discs?
Studies using MRI and arthroscopy have shown displaced discs in people with symptoms of TMJ pain and dysfunction as well as in people without symptoms. So many people without TMJ problems have displaced discs.
Does a Dislocated Disc Cause Pain?
Pain may result from an anteriorly displaced disc. However, it is not caused by the disk itself. Rather, it is due to compression of the highly innervated tissue (retrodiscal tissue) attached to the posterior aspect of the disc located in the slip area between the condyle and skull when the disc is displaced anteriorly and may cause discomfort in the muscles and ligaments surrounding the head, neck, and face.
Many factors can contribute to the development of an anteriorly displaced disc, including jaw misalignment or asymmetry, misalignment, clenching or grinding of the teeth, posture problems, or trauma.
Some symptoms of an anteriorly displaced disc include jaw pain and headaches, earaches, limited jaw movement, jaw clicking, and potentially locking of the jaw.
Should a Displaced Disc Be Treated?
A displaced disc does not necessarily need to be treated. If the disc is limiting movement and causing pain, treatment may be required. However, if there is a displaced disc that is painless or without limited mouth opening, no treatment is needed.
A variety of treatments are available to help accurately diagnose and alleviate some or all of the discomfort caused by an anterior displaced disc. It’s important to get in touch with your doctor to create a treatment plan that best meets your unique needs.
