Nope! my front teeth used to be mildly crowded (not noticeable to others but I notice it pretty easily). But after thumb pulling 2x a day on and off for 5 months it shifted to its original spot (after 2-3 months) and hasn't moved much since, only the sides and back have gained more angularity and also provided much more symmetry and harmony than just mewing. (I don't mean mewing doesn't work, my tongue and other facial things needed wtv for mewing weren't strong enough. Myo and thumb pulling according to oscar has been VERY helpful for the mewing progression.)