That's what is so difficult and devastating with what we have to deal with. Not only do you have to fix the jaws but also do myofunctional therapy, neck and back therapy with exercises and medical massage. Relearn the proper breathing etc. Myofunctional therapy works towards resolving tongue thrust, open mouth posture, attaining nose breathing full time, correct posture etc. Most people with jaw issues don't have enough room in their mouths ideally for their tongues and not as much airway space. This makes it so hard without the jaw surgery to do what others just do easily.