for the ulcer drink raw cabbage or potato juice on empty stomach, about 4 ounces
if it were me i'd accrue debt to get the tooth taken care of instead of risking seizures. sounds like you aren't thinking clearly. money will be of no use to you without your brain working properly.
you can't do traditional chelation with the fillings still in but you can do natural things like saunas and certain herbs or diet changes or cleansing like you mentioned. maybe try taking some Bentonite clay or gargling clay in your mouth.
but the main issue is getting the tooth taken care of asap. it can't be that much money if it's only one tooth. beg borrow or steal the funds.