TMJ syndrome is in the eye of the beholder.
The dentist sees malocclusion and nocturnal bruxation as the cause (teeth that do not mesh well when biting, along with grinding your teeth at night.)
The psychotherapist sees a person grinding their teeth at night because of stress. They try to treat the mental causes of the stress and probably send many patients to dentists to make nighttime bite guards for relief in the meantime. I have not seen much real success with bite guards, unless the person just can not be stopped from grinding their teeth at night.
The chiropractor sees misalignment of the upper cervical spine, including the vertebra that joins the skull with the neck, as a major cause of TMJ syndrome. I used to have TMJ syndrome, and it had been very bad for as much as a year at a time. I have not had it in over ﬁfteen years. (It would have been interesting to try the coherent light on it, though! More on that after the following information.)
How did mine go away? Well, when I was in the Air Force, ﬁve days of taking a muscle relaxer took it away. Then, many years later, in my ﬁrst years of being a chiropractor, it came back, big time. It would seem to fade, and then I would sim¬ply be eating and get that big “CRUNCH” in one of my jaw joints like a rock that had shattered in my jaw joint, and it felt that painful. There is something like a disk there, and it was probably part of the crunch. Then I would think, “Oh, here we go again.” I would have pain with all eating for the next month or so, until the next cycle. I would have to eat very gingerly. I believe that in my case, it had to do with a misalignment of my upper cervical spine, and the right chiropractor ﬁnally worked on my spine, and it went away for good. I have personally helped many people with this problem. Typically, the ﬁrst cervical vertebra has rotated such that its right or left “wing tip” is underneath the TMJ on the most painful side. Regarding my patients with TMJ syndrome, many of them have already gone the dental route. If dentistry ﬁxed their TMJ syndrome, they of course do not report a problem to me. I would imagine it is the same way with dentists.