If it's a plastic bowl I would just get rid of it and get him a metal one. Plastic bowls actually harbor lots of bacteria and germs in the scratches and crevices once they start to get worn, so they really aren't a good idea anyway. If it's a metal bowl, then well, I guess just pick it up the second he's done eating and put it up where he can't get to it, so he doesn't injure his teeth or mouth chewing on it.
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