misunderstanding new mask use

Last night I finally tried a F10 for the first time. Had it on about 2.5 hours and am now a bit confused. I had a VERY low leak rate, best ever, but the worst dry mouth ever!! I thought if you used a pillow mask and had large leaks, that a F10 mask would let you mouth breath some with out penalties. Don't recall reading that mouth breathing was a bad thing with a ff mask as you get dry mouth along with low leak....Please unconfuse me!

Any mouth breathing will dry your mouth out. I use a soft cervical collar to help keep my mouth closed while sleeping. I have found it has helped my mouth from drying out so badly. I am only a mouth breather while sleeping. During the day, I breathe through my nose. I am trying to learn to use a nose pillow mask. Last night, I tried taping my mouth for the first time. I have never had such a dry mouth as I did last night. After three hours, I gave up and went back to my F20 mask.

Mouth breathing with a full face mask may dry out your mouth even though you have very little leakage.

I use a simple black hair band from Target to keep my mouth closed. I find it's more effective and comfortable than the official CPAP Chin strap that I have. (not to mention cheaper to replace)

It's the mouth breathing that dries out the mouth...doesn't matter if it is with a full face mask or nasal pillow mask.
Now for some people the added humidity (crank it up) will offset the mouth breathing when using a full face mask and dry mouth occurs but often it doesn't.
That's why I say that full face masks don't guarantee no dry mouth...they do fix mouth breathing leaks though.

To really fix dry mouth you have to fix the mouth breathing...or add one of the many products designed to help prevent dry mouth.

I don't know that it is really the 'mouth breathing' that does it, per se. Bear with me for a moment...

I woke up this morning, and the skin of my face that had been within the confines of the FFM, was very dry and wrinkled. My skin has never been wrinkled before. I think it is the air that is drying it out, regardless of whether it is your skin or your mucous membranes. Whatever is exposed to that air is going to dry out.