TMJ is an acronym for temporal mandibular joint.  That is an anatomical
structure.  Saying you have TMJ is like saying I have knee.  Now,,,,,,,,,,,
you may have a disorder of the TMJ.  No way to tell without a physical exam.
Most people who complain of problems with this joint are really complaining
of problems with the muscles which control this joint.  Most cases resolve
nicely if the muscle spasms are made to go away.  This is NOT a problem with
your teeth shape or position, so rebuilding teeth or orthodontics (which
might be needed for other reasons) will not make a problem of the TMJ
structures go away.

We can discuss normal and abnormal muscle function and its treatment if you
like.

[Posting from AMF]

Hey Morgan, usually for me these periods of pain are preceded by
something like a really huge yawn (and maybe a *crunch*) or a visit
to my friendly dentist. It does get better after a while but I use
a muscle relaxant (valium 4mg) before dental appointments to
prevent the muscles from mucking about. Makes the dentist's job
easier too. :-)

I doubt it's the bed or pillows that are to blame, could be pain
referred from the neck though? If it's really painful, a visit to
your GP/PCP wouldn't do any harm. Oh, or you could be clenching in
your sleep.

Anyways, hope you feel better soon!