A functional orthodontist places emphasis on the facial profile as well as straight teeth when doing orthodontics. In other words, beautiful faces as well as beautiful teeth are the goals of treatment. Functional orthodontic procedures do not cause TMJ problems and will address existing TMJ disorders. Functional appliances are used that take advantage of growth to address under developed jaws and reposition lower jaws that are receded (Class II bites) or too far back. Patients treated with functional orthodontics normally have nice full lips, a nice profile, and no TMJ problems. Teeth crowding is usually addressed by expanding the jaws to their genetic potential (the size it would have been if normal growth occurred) instead of pulling teeth.
Traditional orthodontics is how university trained orthodontists are taught and the methods have not changed in almost 100 years. Their primary emphasis is how straight teeth are when treatment is completed without regard to what the patient's face or profile will look like. Crowded teeth are usually treated by extracting 4 perfectly good premolars and retracting or pulling the front teeth back to close up the excess space created. This retraction causes the face, especially around the lips, to look caved in and make the nose and chin more prominent. There are often deep creases around the mouth also. This retraction of the front teeth will also cause TMJ problems by forcing the mandible or lower jaw back too far.
Traditional orthodontists also do not know how to advance the mandible in patients with retruded chins (Class II cases). A functional orthodontist will use a functional appliance that will reposition the lower jaw forward to where it should be to create a nice straight profile. The lower jaw will be lined up properly with the upper jaw. A traditional orthodontist will extract upper teeth and pull them back to minimize the appearance of having a retruded lower jaw. The mandible's position has not changed at all and a lower jaw that is too far back and not lined up properly with the upper jaw will remain so.
Unless you are a dentist interested in doing orthodontics, you will not hear about functional orthodontics because it is not a layman's topic.
functional orthodontist who have corrected many TMJ problems caused by traditional orthodontic technique