Especially for Braces Wearers Do you absent-mindedly commit Tooth Abuse? These are habits definitely off limits for the health of your teeth: Don't chomp on a toothpick—it can wear teeth down and get caught in your braces. Stop chewing your nails, pens and pencils—it's hard on teeth and gums. Leave the ice in your drink? Chewing ice can crack teeth and fillings, and pop wires in braces. Don't consume something very hot just after something very cold. The rapid expansion and contraction can crack dental enamel. Treat your teeth right!