Stomatitis and Hill's Prescription Diet T/D

My senior male has been diagnosed with stomatits, and I've been trying
to read up on it. I'd appreciate any tips, advice, etc.

Does anyone have opinions on Hill's Prescription Diet T/D? This hasn't
been recommended to me yet, but I read about it and was wondering if
it might be beneficial. I also have a little sprite of a cat who is
three....should she be eating it for her teeth? She'll eat whatever
she gets. My boy is very picky. He hasn't yet had his dental - on
antibiotics to take down the swelling first. So I don't yet know how
extensive this is, or if he'll lose any teeth.

Thanks!