I agree that a chinstrap will help. I use the Quattro FX, and have to use chinstrap. I get the dry mouth as you do, without it, and I know what you mean about the pain. I have tried pillow masks, but even with the strap, the back portion on my mouth gets dry. If you can, try to get DME to let you try different ones, using your mask, to check if it is comfortable, or at least, bearable. It is a lot of straps on your head, when going to sleep is already trying. I do have a F&P FlexiFit 431 I am still trying to use, that has a lip that seals under the chin, that does not make me use strap, but am struggling with pressure placed on bridge of nose. It is actually the quietest mask I have used, so far. Don't even hear my own breath. So, I will continue to work with it. Hope this helps.
I agree that this happens when your mouth allows air to escape while you are asleep. With a full face mask, I have encountered the dry mouth problem. If what trailrider suggests works that would be fine. If not, I suggest that the next step is to try a chin strap. Chin straps are kind of like masks, they work differently for different people. I tried 3 or 4 before I found one that would even stay in place for the whole night. Even at that, the chin strap did not work for me. Still had dry mouth and mouth leakage during the night. Therapy was OK because the system did not lose pressure.
The next step is to train yourself to keep your mouth sealed. This has been discussed a lot to enable people to use nasal pillows or nasal masks without mouth leaking/breathing. The seal need not be perfect in order to be of help for this problem but in my opinion it does need to be fairly effective. I still can not seal my mouth well enough to use nasal pillows or mask, but I get enough improvement that between the reduced leakage and humidification I can avoid the dry mouth. After a while, I may start to get dry mouth again and have to increase my tongue seal training again for a while but overall it has worked for me.
WELCOME! to the forum.!
You might try a chinstrap, and also, you might turn your humidity back a few notches. Too much humidity can be problematic as well as too little.
Much success to you as you continue your CPAP therapy
Thanks for the responses, everyone!
I do have a chin strap and have used it with the Swift FX and the N10. In that scenario is when I get the terrible burning in my sinuses. I've tried the humidity set 1/2 way up, 3/4 and all the way. I've also tried Auto. Nothing helps.
The dry mouth is while using a full face mask, the AirFit F10. The pressure pushes my mouth open even though I'm not leaking. Then I get the dry mouth, or wake up and close my mouth again, which is almost as bad as the apnea.
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