So sorry to hear about Lani.
You may have to risk the dental sooner than later. If the tooth/teeth are abscessed and causing her major non-eating problems, that is not going to improve with time. You may end up with a cat that is malnourished having to go under anesthesia, which is much harder on them. I had that conundrum with Emily -- she was old 15-16 years with problem kidneys, but bad teeth so she wouldn't eat. The not-eating IS fatal, the dental isn't fatal, so we opted for the dental the next day. (And she lived another 3 years!)
In the past, I have used (on me and cats) a homemade concoction for tooth problems, such as abscesses. Here's a link to a version of the recipe -- http://www.ehow.com/how_5102760_make-powerful-natural-mouthwash.html
The one I use also had 1-2 drops of goldenseal. With cats, I use a q-tip and swab some hydrogen peroxide on the gum line, wait a 30 seconds, then swab some of this natural mouthwash on. Cats don't like it, but it will clear up small infections.
Thanks Linda. Lani is eating and maintaining her weight, she just won't eat canned and only eats small amounts of dry at a time plus she is not taking in fluids. We are going to do the dental but we have to get her stabilized from the Amox reaction so her body is capable of dealing with it, plus we need to wait to give her antibiotics so it will be probably in 1-2 weeks.
She doesn't have an abscess, they think she has what would amount to a bad cavity to us, it is called FORL.
Thank you for the link, I will check into that, it may help with the dogs too.