collar use, TMJ and wake up events

[fotjon]

When I don't use the hard collar to sleep, i tend to wake up with mouth filled with air. Also I have double the CA events than usual. I wonder if the pressure to high or the tongue in the wrong position, but i think is the jaw dropping down, the real problem. I do have neck and TMJ issues. I have set the pressure to 9 in cpap mode or 6-10 in apap. The mouth also seems a bit sore when this happens, like I'm mouth breathing and i do have just a nasal mask. Is the use of a collar common for people with severe sleep apnea?

[cdplatt]

I doubt if your pressure is too high.  It would be helpful if you used OSCAR and posted some charts.  However, it is common for people to use collars to keep their chin from dropping while sleeping.  Based on you description, I'm pretty sure that is happening to you.  If you find the collar uncomfortable, you can try mouth tape to keep air from escaping through your mouth.  That works well for many.  You might also try a full face mask.