There are three categories of nail biters: the nibbler, the biter anf the cannibal. Nibblers will just lightly nip the nail with their teeth. Biters will bite off the free edge and cannibals will bit the nailoff as well as bite into the healthy flesh where the nail will end up much shorter than the pink of the nail bed. ANY habit can be broken - it is said to take only 30 days. You need to solicit all your family and friends to tell you to stop whenever they see your fingers in your mouth. Also, book a series of manicure appointments so the nail tech can safely remove anything that is sticking up or rough so you won't have the tendancy to bite. Keepign the nails as nice as you can will help to break the habit - especially when you see results. If all else fails, have short nail enhancements applied. Since nail biters are on a quest for order, nail enhancements will create that instant order. They are also very difficult to bite :) Just be sure that the technician does not apply them any longer than the tip of the finger or they will break easily.