Hi Janey,
This might be related in a way you haven't mentioned. Going to the dentists involves you keeping your mouth open for extended periods of time, which can aggravate the muscles (that are already sensitive) and cause you pain. Try and find a dentist in your area that treats TMJ disorder, but keep in mind that there is no specialty for these dentists, so make sure you research his qualifications before hand.
If you have any questions please don't hesitate to contact me. I have been going through this TMJD stuff for over 10 years.
Hope you are feeling better,
stacy http://www.tmjfriends.com