Beginning with its founding at the start of this century by Edward H. Angle, the orthodontic profession's primary concern for its first forty years was the relationship of teeth. Orthodontists' efforts were directed towards how the teeth interdigitated. Since the early 1940's, due to the influence of Doctors Tweed, Brodie, Steiner, Margolis, etc., emphasis has been placed upon the effects of orthodontics on the patient's profile, and the profession was then concerned with both esthetics and tooth function. There are two final areas into which the bulk of the orthodontic profession has yet to move, and they are the areas of the temporomandibular joint myofunctional therapy. Orthodontists must now begin to incorporate TMJ function and the results of myofunctional therapy into their thinking and into their treatment plans and realize the effect they have upon improving the skeletal muscle, neurology and physiology of the patient's face as well as his facial esthetics and the cuspal interdigitation of his teeth. The dental profession as a whole must not only realize the role myofunctional therapy has in attaining these goals, but the role it plays in maintaining their subsequent stability.
Stack, B. C., & Funt, L. A. (1977). TMJ dysfunction from a myofunctional prospective, International Journal of Oral Myology, 3 (1), 11-26.