I find it unfortunate that your beloved pet, who gave you the best years of his life, is not worth a vet visit in his senior years. Senior pets almost always need more medical attention than young animals do (people too, for that matter). Didn't you consider this when you got him in the first place? Problems like the ones you mentioned (ear and teeth) do not go away on their own. They will only cause more pain and suffering as the days turn into weeks. Reconsider taking the cat to the vet or find someone else who will care for him properly.