I too was sent to my dentist for a splint for my TMJ, which I did not actually have. ::)
Regarding the MRI:They gave me headphones for my MRI and offered me a choice in music. I chose something relaxing and then went to one of my "happy places". In my terribly busy world, it is not often that I find 20 minutes of uninterrupted down time. I listened to instrumental music, kept my eyes closed and did my relaxing breathing. I never opened my eyes and I think that helped me to not feel the confinement of the MRI tube. It's like when I give blood. I don't mind it, but I never watch them put the needle in my arm.
!Happy Place!HappyPlace!HappyPlace!