Does dementia for a 90 year old qualify them for nursing home?

The minute my Mom was diagnosed with dementia, I was told she could not be alone. She was in the early stages then. Now she is mid-stage & I'm trying to figure out how to get her in Long Term Care and attended a class yesterday. We will see if. I can get her in without her punching me in the face.

There are many stages of dementia, those in early stages often still live at home, sometimes alone. Only a doctor can make the call whether 24\7 care in a nursing home is necessary.

Get a good comprehensive geriatric evaluation. It would put your mind at ease in regards to not willing versus not able, and give you a better idea of what kind of care the person really needs, as well as any options for treatment that might improve things. Some 90 year olds can be independent or just need a little physical help for years; some 75 year olds can't manage to do anything without damange to themselves or others, but may put up a good front.