Took my cat to the vet last year, as she wasnt eating, he said she had bad teeth took all of them out except 1 at the front, he ex[plained the anasthetic may well kill her as would the shock.
6 hours later, prepared to pick up a dead cat, got there, almost crying, (some men do love pussies), vet went and got cat, she had just one tooth, meowing like a kitten,paid the 86 quid, she was stil alive, took her home, and she became a kitten again despite being 16 years old, running round, jumping and being playful, absolutely no sign of pain in her mouth or elsewhere.
She hasnt looked back, just cant bite the other cats loclly , but has hell of a spit and hiss for an old cat.
Animals are so adaptable, and so grateful when you gfet them fixed, well worth the 86 quid.