Because her brain is no longer able to tell her mouth to close due to the dementia. My husband developed aspiration pneumonia while he had vascular dementia, and I was told by his doctor it was because my husbands brain was no longer telling his throat to close while he was eating, allowing the food and drink to go into his lungs. Our brains control literally everything that our body does, so it should be no surprise when someone with dementia is no longer able to do certain things, as their brain is now broken and will never get better.
My FIL did this at the end of his life--and I think his was due to the fact his dentures did not fit well and his mouth was sore a lot.
My DH does it too and he's fine. He has a tooth that needs to be smoothed out and he lets his mouth kind of hang open as he's annoyed by this tooth.
There could be a myriad of reasons. If it bothers you a lot, follow up on just having her teeth checked, otherwise, just adapt to it. I know it does make someone look kind of 'older' with a mouth that hangs open. IDK why, but it does.
She wears dentures only when we go out of the house. But when she’s at home with her teeth out she still does it. I thought it was the dentures too. May have been at one time. Now it’s a habit and/or the brain not telling her to close it. When I say “close your mouth” she immediately does it.
Probably part of her Dementia which now controls her brain. Just like if not already, she will become incontinent. Its not the muscles you use to "hold it" that is the problem but the brain sending signals to the muscles to hold it. If that part of the brain is damaged, then signals are not being sent out.
My husband developed aspiration pneumonia while he had vascular dementia, and I was told by his doctor it was because my husbands brain was no longer telling his throat to close while he was eating, allowing the food and drink to go into his lungs.
Our brains control literally everything that our body does, so it should be no surprise when someone with dementia is no longer able to do certain things, as their brain is now broken and will never get better.
My DH does it too and he's fine. He has a tooth that needs to be smoothed out and he lets his mouth kind of hang open as he's annoyed by this tooth.
There could be a myriad of reasons. If it bothers you a lot, follow up on just having her teeth checked, otherwise, just adapt to it. I know it does make someone look kind of 'older' with a mouth that hangs open. IDK why, but it does.