TMJ and Trigeminal neuralgia (TN) have a lot in common. I think what’s missing from the information I found on Wikipedia (and via Google) is that TMJ can cause TN.
Trigeminal neuralgia… is a neuropathic disorder characterized by episodes of intense pain in the face, originating from the trigeminal nerve… It has been described as among the most painful conditions known to humankind. It is estimated that 1 in 15,000 or 20,000 people suffer from TN, although the actual figure may be significantly higher due to frequent misdiagnosis. In most cases, TN symptoms begin appearing more frequently over the age of 50, although there have been cases with patients being as young as three years of age. It is more common in females than males…
TMJ is also more common in women than men. What has confused TMJ researchers is that some people have TMJ but don’t have that much pain or any pain at all, while others have intense pain. Since the TN nerves are part of the jaw joints, it just makes sense that these nerves can be a part of TMJ pain.
This disorder is characterized by episodes of intense facial pain that last from a few seconds to several minutes or hours… To describe the pain sensation, patients may describe a trigger area on the face so sensitive that touching or even air currents can trigger an episode; however, in many patients the pain is generated spontaneously without any apparent stimulation. It affects lifestyle as it can be triggered by common activities such as eating, talking, shaving and brushing teeth. Wind, high pitched sounds, loud noises such as concerts or crowds, chewing, and talking can aggravate the condition in many patients. The attacks are said by those affected to feel like stabbing electric shocks, burning, pressing, crushing, exploding or shooting pain that becomes intractable…
Since I describe my facial and head pain as constant and not episodic, I didn’t think that I suffered from TN. But since I was forced to stop treatment with prescription medications, I have developed pain storms that are more episodic in nature. The pain flares don’t last for minutes or hours, they last for days, and the triggers are very similar.
When pain levels are constant and at such high levels, it’s very difficult to differentiate between joint/bone pain and nerve pain, so patients have a hard time relating this kind of information to doctors. I think TMJ pain starts out as joint/bone pain, but can easily develop into nerve pain.
As with many conditions without clear physical or laboratory diagnosis, TN is sometimes misdiagnosed. A TN sufferer will sometimes seek the help of numerous clinicians before a firm diagnosis is made.
The only way to determine problems with the jaw joints is by MRI, but even that test doesn’t always accurately diagnose TMJ. Since dentists diagnose TMJ through things like clicking and range of motion in the jaw, and symptoms like headaches and facial pain, MRIs are not usually performed. Plus, MRIs are expensive and not covered by insurance for TMJ, especially if ordered by a dentist.
There is evidence that points towards the need to quickly treat and diagnose TN. It is thought that the longer a patient suffers from TN, the harder it may be to reverse the neural pathways associated with the pain.
This is true with just about all pain, which usually starts out as acute and then develops into chronic and intractable pain. Once pain is chronic, there is no going back, which is why treating pain early is so very important. Doctors used to know this, but the drug war has caused doctors to be more cautionary when treating pain, including refusing to treat it.
The differential diagnosis includes temporomandibular disorder. Since triggering may be caused by movements of the tongue or facial muscles, TN must be differentiated from masticatory pain that has the clinical characteristics of deep somatic rather than neuropathic pain. Masticatory pain will not be arrested by a conventional mandibular local anesthetic block.
To diagnose my TMJ, the dentist performed nerve blocks which did not stop the pain. This test differentiated dental (tooth) pain from jaw pain. But perhaps my diagnosis should have also included TN. Not that it matters, as there are very few treatments for both TMJ and TN. And a lot of those treatments just make the conditions worse, especially surgery. You cannot cut into facial nerves and expect the trauma to not make the pain worse. In fact, my TMJ surgery might have actually caused the TN.