I've made teeth out of hot glue that have worked great I usually use this method when making single teeth (buck teeth for example, or the one-tooth back woods kind of puppet)
lay out wax paper and using a hotglue gun lay down a layer of hot glue, place two pins side by side in the hot glue, and squeeze out a little more glue on top of them so that the pins are in the middle of the future tooth, when it's dry using an x-acto knife cut the tooth to size, making sure the pin head is in the center of the tooth, now the tooth will be clear but use white nail polish (putting on a couple of layers) to make pearly whites or yellow if the puppet has a gum disease or black if the disease is really bad you get the idea,
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