CULLP is a term used to describe when patients have an asymmetric smile, but the corners of their mouth go up nicely and the remainder of their face works normally, but during smiling they are unable to show the bottom teeth on a single side. When kids are born with this, their smile looks quite asymmetric. Luckily, it is relatively straightforward to treat, with a simple weakening technique to the opposite side, which restores balance, and dramatically improves the appearance of the smile. Usually when kids are old enough, we perform a tiny injection in the office to be certain that they like the effect, and then we can go ahead and actually remove the over-active muscle in the opposite lower lip, to restore balance. There are also emerging techniques to restore movement to the opposite lower lip, and we are very likely to see some of these techniques perfected in the next decade.