I was referred to a consultant last year for TMJ,very painful jaw, couldn't chew, yawn or sleep had dental X-rays , no tooth decay or anything obvious
I then had an MRI and apart from narrow joint space there was no disc displacement, which is indicitive of TMJ, so he sent me for 6 sessions of physio.
Upshot was that the problem was in my shoulder, and after massage and ultrasound it gradually improved, probably over 3 months. Physio said my shoulder and neck were very tight.