Krokus is only 4, but his teeth feel a bit worn down to me. He is a strong chewer, and he gets a lot of satisfaction from chewing his Nyla-knot. He has a Goughnuts stick, but he never chews on it. He also likes petrified bones, but mostly if they have peanutbutter in them. Is there some chew thing he might find satisfying, that won't be so hard on his teeth? Tracy