What to look for in dentists for a late stage Alzheimer's patient?

Mom has late stage Alzheimer's and is in an excellent facility. Tonight when I was feeding her I heard a crunching although the food they were eating was soft grilled cheese and soup. We left her alone in terms of care because it didn't make sense to cause additional stress. Now she needs dental care and we don't know how to handle this. Multiple trips from a rural area will stress her body and no local dentist will agree to take her because she can't communicate with them. We can't even check her mouth because she bites and cannot understand. Help!