[LunarBerry]

I recently saw some "tooth sponges" that I though were really interesting. They have this small, somewhat thin square sponge on the end of a sort of ring. Suppose to get into harder to reach spots which I was thinking wasn't a bad idea, especially for smaller dogs or puppies. I looked at those finger brushes and then thought that looked a little big/uncomfortable for little puppies, but fine when they are older adults. It says you can use it alone or with doggie toothpaste. I plan to eventually get those, myself, as it looks like it'll be good to start with.
Otherwise we've used small or baby human toothbrushes (with soft bristles) before and it seemed to be fine :3