TMJ Locking: Acute Lock Versus Chronic Lock. Acute Close Lock of TMJoint Should be reduced ASAP before Permanent Damage Occurs

A frequent occurrence in high school and college age women is an Acute Close Lock of the TMJoints. This usually occurs in patients who have a history of TMJoint clicking but it can also happen following trauma. There is a disc that divides the joint into an upper compartment and a lower compartment.

As I write this article I have a college student under high stress of midterms and papers due in my chair. She has been locked about 36 hours prior to her visit has 18 mm of interincisal opening and severe pain with movement. Opening past 18 mm her jaw deviated sharply to the right indicative of Right side. After reducing the dislocation it opened straight and to 31 mm. Prior to reducing the dislocation she could move her jaw to the right without pain but even slight movement to the left created sharp pain. Protruding her jaw forward was pailful and the jaw deviated to the right. Learn more about TMJ Disorders at


Patient testimonial:

For this patient the diagnosis was acute close lock (medial anterior) of the Right TMJ. Following reflex reduction of the Right TMJ she could open (forced) to 41 mm without Joint pain but there was right masseter muscle pain. An orthotic was constructed to maintain the TMJoint position. This patient was seen a few months earlier and she declined treatment because she did not want to have to wear an appliance in her mouth at school. After experiencing the severe pain of a close lock she is very happy having an appliance in her mouth. Sometimes patients decide to quit their orthotics and often del fine for several days until the TMJoint locks again.

TMJoint Locking is different than being unable to open due to muscle spasm or myositis. The treatment for myositis is different than for a TMJ close lock. The best treatment for myositis is is nsaids, possibly muscle relaxers, icing and stretching and most important, time.

The same treatment for an acute close can be a disaster, ideally you want to reduce the close-lock as soon as possible. This can be difficult and sometimes is done under IV anesthetic or without and the oral surgeon manipulates the jaw to reduce the dislocation.

The alternative which is usually easier is to stimulate the opening reflex that instantly relaxes all of the elevators Mouth closing muscles) of the mandible and activates the opening muscles (supra hyoid muscles and infra hyoid muscles) This reflex gives instantaneous opening straight down like a snake and allows disc recapture. It is extremely important to have an emergency orthotic to prevent recurrence of dislocation. As soon as the disc dislocation is reduced the joint will begin healing, if your joint is in a closed lock continuing damage is occurring.

An open lock TMJ is completely different treatment. This occurs when there is a subluxation or movement of the condyle out of the joint and I will discuss in a future article. This is usually secondary to trauma, a wide yawn or over-opening to bite into sandwich or apple.