DH is a dentist & he has had some little story books in his office in the past that he has let the "little thumbsuckers" borrow. This is a good positive reinforcement tool. For kids a little older, he has had the parents bring the child by the office for a between check-up "evaluation", basically just to give the child lots of encouragement & positive reinforcement for efforts made. No scolding or scary stuff! I'll try to see if I can get the title of the book - but you could probably do a search on Barnesandnoble.com, etc. Another thing that we did with our own younger daughter was to make a big deal of getting to have fingernail polish (just a pretty little-girl pink) when she remembered to not suck. I've also heard my husband suggest fuzzy mittens to be worn at night. Good luck & don't worry too much!