USC University of Southern California

Herman Ostrow School of Dentistry of USC

Gentler Help for Locked Jaws

Just as with other joints such as the knee or hip, problems in the temporomandibular joint, or TMJ, can lead to popping, clicking, movement limitations and debilitating pain.

But surgery for the hardworking jaw joint is not always the best answer, cautions Glenn Clark, director of the USC School of Dentistry Orofacial Pain and Oral Medicine Graduate Program.

“Over time, the trend has been for treatment to get less invasive and more conservative,” he says.

Many TMJ problems occur when the cartilaginous disc inside the joint moves out of place or folds over inside the joint. This “internal derangement” usually causes pain and jaw locking and in previous decades was treated with very invasive open surgery, Clark says.

In the mid 1980s, Clark was one of the pioneers in promoting arthroscopic surgery techniques for the TMJ, co-editing two books on the topic. Both books were based on conferences. Surgical TMJ arthroscopy employees specialized tools with cameras that send images from inside the joint to a monitor in the operating room. This method clearly reduced the invasiveness of joint procedures while providing a substantial degree of relief for TMJ patients.

“It was a great improvement over what had been done before,” Clark says.

But surgical arthroscopy was still not an ideal option, as it required expensive specialized equipment and a large surgical team, and arthroscopy fell out of favor around 2000 when arthrocentesis was developed. The new procedure uses two needles to flush the jaw joint with fluid; the results and level of invasiveness are similar to arthroscopy while the equipment and personnel costs are much less.

But Clark adds that surgery is still too costly for many of the working poor that the USC School of Dentistry serves, Clark adds. And while simply waiting out the problem can sometimes bring relief, the wait can take months or years – a large price to pay for patients who miss work and other activities due to jaw problems and can often develop neck, head and shoulder pain as side effects.

Luckily, Clark and his team have had good results with a new and much more conservative technique called anesthesia assisted mobilization. During an outpatient office visit, a combination anesthetic and steroid injection is administered to the joint, the jaw is manually mobilized (stretched open gently) to increase mobility and the patient is taught self-stretching exercises to be performed at home.

“A large part of this minimalistic approach is the self therapy, including stretching exercises, use of bite guards and taking pain medication properly,” Clark says.

The patient is only anesthetized locally for the procedure, unlike the use of intravenous sedation employed during other types of jaw surgery. Most importantly, the success rates of anesthesia assisted mobilization are equivalent to jaw surgery, according to clinical empirical evidence.

Clark says anesthesia assisted mobilization is gaining in popularity and hopes that clinical studies will eventually quantify when and on whom it is most successful. The trend toward for more conservative treatment for TMJ problems is a good thing, not only for patients who can now more easily obtain relief from jaw locking and pain but also for doctors who want to treat the problem with fewer risks and negative side effects, such as arthritis, scarring and post-surgical infection.

“With MRI imaging, we now understand more of what’s going on anatomically,” Clark says. “We don’t want to under-treat the problem, but we also don’t want to over-treat.”