Brief Answer:
Orthopantomograph, T Scan, medication, avoid dental treatment

Detailed Answer:
Thanks for your query. I have gone through your query.
As far as you TMJ issue is concerned, it can be secondary to any malaligned teeth like deep bite, bruxism and other factors like stress. So you need to get the cause treated. You consult a good oral physician get it diagnosed first. Later we can treat accordingly. if there is a deep bite that needs to be corrected. if there is any high points that needs to corrected. Till it get diagnosed we cannot treat.
Regarding your dental appointments, you can request and explain your dentist about you problem, so that he can do treatment for short duration since keeping your mouth open for long time will result in TMJ issues again. You can opt for short duration appointments.
Better to avoid treatment procedures when you have TMJ issues. Once the symptoms subside then you can go for dental treatment.
If I am you treating doctor, I would have advised radiographs like orthopantomograph and T Scan to find out the cause and mean while I would have suggested to take tablet piroxicam for 5 days and give rest to the joint by not opening mouth wide and apply hot fomentation over the joints.
I hope I have answered your query. If you have any queries reply me back. take care.
Thanks.

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