Myths that persist about orofacial myology.

This article addresses many myths that have persisted over the years in dentistry and orofacial myology regarding the nature of orofacial myofunctional disorders (OMD's). Myths include 1) the concept that the term "tongue thrusting" includes the rest posture; 2) that there is an excessive amount of pressure exerted against the anterior teeth in swallows, that swallowing pressures add up, and the frequency of swallowing has an impact on the dentition; 3) the idea that the tongue is the strongest muscle in the body; 4) the view that a muscle will be the winner in any tug of war between muscle and bone; 5) the claim that a tongue thrust can cause an open bite malocclusion; 6) the claim that a tongue thrust can cause a Class II malocclusion; 7) the claim that the tongue molds the palatal vault; 8) the notion that a low tongue tip posture at rest presents a problem; and 9) the claim that OMD's represent a muscle imbalance that can be brought into balance with therapy. Each of these false claims or "myths" is discussed and corrected, with the positive acknowledgement that clinicians are abandoning the incorrect notion of muscle balance and imbalance as had been claimed previously.