Mouth-taping with 3M micropore tape to avoid dry mouth in morning! Read Jim Nestor's book, Breath. You'll be amazed! I simply cannot sleep without my mouth taped. [Yes, all my doctors look at me weirdly, except my dentist!]

Glad you responded to that part of my post.
I wonder how many others who have been diagnosed with BE did/do sleep with their mouth open.
For some reason I have not been waking up with the terrible dry mouth I was having a little over a year ago. I have to assume I still sleep with my mouth open...at this time there is no one in the house to observe me sleeping. Have to have a sleep over and have them come into the bedroom to tell me if I still do. Ha! I did not know I was sleeping that way until I was told that I was.
Possibly the therapy we do for BE has helped, possibly since I am now putting moisture into the house (boiling lots of water for the various reasons related to BE) and keeping the house temperature low so not to have the heating system dry the house out, has helped. Don't know.
My Mother began sleeping that way late in life, she had emphysema.
I have given thought to this, this last year and a half, and wonder if sleeping and breathing through the mouth can not only cause dry mouth but also dryness in the lungs or if the breathing that way makes one more susceptible to infection??? Don' know, but my belief is that most things in life are caused by more than just one thing.
I haven't found anything on line on how to stop the breathing through the mouth at night other than posts suggesting taping the mouth closed. I did try that for a while before being diagnosed with BE. They suggest micropore tape placed in the center of the mouth area between the upper lip and lower lip. Not a perfect solution but less breathing in of air etc. Since I no longer wake up with the terrible dry mouth and since I have to clear my throat of mucus build up at night when I wake up to visit the bathroom, I don't do that anymore.
And so, that's my story with mouth breathing at night. Glad we all can share our experiences.
Barbara