My husband (with advanced dementia) does not like to be changed and gets very angry with the aide trying to clean him.

Does he happen to call her derogatory names and/or yell "Get the hell out of here"?

If DH is rational at all, you could try telling him that he MUST be changed or he will eventually be in hospital with illness. If he WON”T let the ‘nice’ aide change him, you will have to hire a second aide to force it on him. The cost of that will be prohibitive, so he will soon need to go to a facility where there are always two aides available. It’s all true!

Could you try having a TV visible from the bed, so that he has something else to focus on besides the aide? A car race, with headphones on loud?

An experienced aide will plow thru this with determination and get the job done each time, ignoring outbursts and yelling or cussing. It's common behavior with dementia. If his aide is unable to handle these brief changes, it's time to hire a new aide who HAS experience with angry dementia patients. Or, get him placed in a Memory Care Assisted Living facility or SNF where it's an everyday occurrence for the staff. You can't change HIM unless you try giving him Ativan to keep him more relaxed in general.

Good luck to you

This isn't uncommon. Due to our history of toilet training never leaving us, it often survives when all other memories have long gone from us. If this is the only problem with outbursts I would discuss with the aid. If she/he is able to muster through these times, that is great. If not, and if it is becoming impossible to keep your husband clean you may require placement where there is more than one staff member involved in changes, or some thought to medications that may help your husband. So sorry. This is just hit and miss and try anything-everything. Wishing you good luck.

Have you thought about having a catheter placed in him so all you'd or the aide would have to worry about was when he pooped? That would certainly cut down on him having to be changed.
Also you could try giving him some of his anti-anxiety medication(if he's on any)a half hour before he needs to be changed to see if that makes him more calm.
Other than that I got nothing, but perhaps others on here may have some other suggestions.