The MAS (mandibular advancement series) difference.
ABSTRACT So now it may be seen what is meant by the term "The MAS Difference". The American orthodontic specialty has for the most part been slow, or even in isolated pockets, willfully resistant to expansion of orthodontic technique up out of the "Procrustean bed" of fixed appliance limitations to the panorama of attacking the teeth-bone-muscle triangle of malocclusion with separate techniques and appliance systems designed specifically for each. What makes this anathema to those of a broader view is that it is only with those expanded, combined fixed AND functional techniques, that one has any chance at all of rendering anything close to significantly successful treatment of major TMJ-pain-headache-dysfunction chronic pain problems. And that is serious stuff. So, if you want to do "ortho" you had better know "TMJ". And, if you want to do "TMJ", at least TMJ to any meaningful degree, you had better know "ortho", and that means the discipline of functional orthodontics (or "maxillofacial orthopedics" if you will). The "why" of it is easily understandable once one truly understands the orthopedic (condylar displacement), myofunctional (Class II neuromuscular sling), and neurological (chronic repetitive compression nerve damage) aspects of the common functionally induced TMJ problem. The "how" of it all is another matter. That is why knowledge of a broad variety of various specific orthodontic techniques is required for the clinician because there are a vast variety of malocclusive situations with their own unique demands. But in the broadest sense, since a major portion of the orthodontic patient population suffers from somewhat of a skeletal Class II relationship, or "Class II effect" with respect to the joint, somewhere in the proposed treatment plan for these patients the clinician will have to consider some form of mandibular advancement series, whatever that series may be. But it is that MAS difference that sets that clinician and his or her specific treatment plan apart from the older, more restricted ways. It is a difference we must pay attention to, for Nature surely will.