Yes, it does sound as pretty difficult situation. It is very honorable that you take care of your mom this way!!
Memox is the same medication as Namenda in US. We use this medication in late-stage dementia and it does help improve a bit of cognitive function for some time (in several months the cognitive function begins to decline again). Aricept is another drug used for dementia but honestly, I do not feel that your mom will get any benefit from it at this late stage of her disease.
The other drugs that you have listed are all behavioral drugs and they are all used in US to help dementia patients be less aggressive. All of these drugs are in the family of anti-psychotics. They dont help at all with dementia but rather, again, helps with controlling behavior. All of these drugs have side effect of sedation so I am not surprised your mom felt the way she felt on them.
It is not necessary to have a nurse in the house all the time in order to have a G-tube. Patients who dont have dementia are actually able to take care of their own G-tubes so I am assuming you or a care taker will be able to do the same with proper instructions.
I understand the teeth problem as well. No dentist will want to put your mom to sleep to have surgery due to her high risk not waking up from it and no dentist will be able to do anything with local anesthesia exactly because your mom will not cooperate. Also, any stressful event for a demented person, will set back their condition even more so if it is not absolutely necessary, I wouldn't recommend her going through such major procedure.
Please let me know if you have any other questions. I will be happy to assist you further.
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