Hubby and I have been adopting old cats for the past four years and had ones with no teeth and one, Lily, who had a broken leg (cage rest for a few months but afterwards she was 100%

). One of our oldies only had two teeth yet still managed to crunch up dry food

Otherwise they would have normal wet food which I would mush up
Hope you get this wee yorkie

No reason why she shouldn't live a normal lifespan and reach 15 years or more