How Two Nerve Systems Interact to Fuel TMJ Osteoarthritis Pain

A team of scientists from Airforce Medical University in China has made a discovery that helps explain why TMJ osteoarthritis (TMJ-OA) is a severe form of TMD. Their study, Effect of regional crosstalk between sympathetic nerves and sensory nerves on temporomandibular joint osteoarthritic pain, published in the International Journal of Oral Science, highlights the role of the sympathetic nervous system in TMJ pain.

The TMJ is different from other joints in the body because it develops from nerve-associated embryonic tissues, rather than the more common mesoderm, the embryonic cell layer which gives rise to muscle. This has led scientists to classify the TMJ as a “neurogenic joint,” meaning it is highly influenced by nerve activity.

The Role of Sympathetic Nerves in TMJ Pain

The study found that the sympathetic nervous system, which controls involuntary functions like heart rate and blood pressure, plays a crucial role in TMJ-OA pain. Researchers discovered that sympathetic nerves in the TMJ releases norepinephrine (NE), which can trigger the growth and activation of sensory nerves. This interaction between the sympathetic and sensory nerves increases pain signals, making TMJ-OA pain.

Why Does This Matter?

This discovery provides a new explanation for why TMJ pain can be so persistent and difficult to treat. By targeting the interaction between sympathetic and sensory nerves, future treatments could be developed to better control or even prevent TMJ-OA pain.

Potential New Treatment Approaches

Now that researchers understand how sympathetic nerves contribute to TMJ pain, they can explore new treatments to block or reduce this nerve activity.

This could include:

• Medications that target nerve signaling
• Therapies that reduce norepinephrine levels
• Nerve-blocking techniques to prevent excessive pain signals

While these treatments are still in development, the findings offer hope for people who suffer from chronic TMJ pain.

Looking Ahead

The discovery of dual nerve system involvement in TMJ pain represents a major step forward in understanding and treating TMJ-OA. As research continues, scientists are optimistic about developing targeted therapies that could significantly improve pain management for patients.