Mark, it might be worth asking the vet for some a/d, very few cats can resist it. They also wouldnt be able to give both a steroid and a Metacam jab, so I would ask which they think will help him more, and I would be swaying towards a steriod jab as he has had Metacam already. I remember when Snowy had all her teeth out (my first toothless cat), I put her biscuits through the food processor and mixed that in with wet food, do you think you could do that with his renal biscuits?