Functional Therapy Revisited
Orthodontists throughout the world owe a debt of thanks to people like Frankel, Woodside, Harvold, McNamara, and Pancherz, who have shown us anew that functional appliances can favorably alter growth and help us achieve the esthetics and function we want for our patients.
Although disputes still exist about how and why the appliances work and which design is the most efficacious, by now the capability of functional orthodontics is indisputable. Teeth and bones are altered by these mechanisms, and the ability to make such changes has excited and challenged orthodontists.
Unfortunately, the functional euphoria that swept across the United States a few years ago has subsided considerably. Many orthodontists have become discouraged because their patients haven't shared their enthusiasm for these unwieldy and permissive appliances. My private (and absolutely unscientific) poll indicates that the orthodontists who endorse the concept of functionals have generally been nonplused at the lack of patient compliance.
In light of studies by Chase and Thomas (Know Your Child, Basic Books, New York, 1987), such a patient reaction isn't surprising. These authors contend that large numbers of people are born with a low sensitivity threshold and remain supersensitive throughout their lives to stimuli that would be unnoticed or ignored by others. Everything seems to bother low-threshold people: bright lights, loud noises, unusual odors and tastes, and tactile stimulation. These are the children who refuse to wear wool sweaters because they find them intolerable against their skin. Combing out tangles in their hair after a shampoo becomes a knock-down, drag-out affair. They are often picky about their food because of the way certain foods feel in their mouths, and they avoid highly seasoned or strongly flavored foods. Their responses to all kinds of stimuli are exaggerated, and combined with persistence--another inherited trait--this tags them as "difficult children".
One should not infer that these individuals have some character defect or sub-criminal tendency. In fact, most "difficult children" grow into responsible adults and live happy and fruitful (albeit sensitive) lives. But these children also exhibit unique responses to dental therapy. My experience shows that they are much more likely to pick at and break appliances, complain about pain, miss appointments, develop auto-immune intraoral ulcers, salivate copiously, have poor oral hygiene, have easily fatigued jaw muscles, and break, lose, or not wear permissive appliances (headgears, retainers, elastics, functionals). There are so many of these children that to exclude them from our practices would leave us just enough income to cover the rent and utilities, and additionally make us look like uncaring elitists.
Most of the noncompliance we encounter is not accidental, but willful and intended. It does not respond favorably to exhortation, which is our most used but least effective method of changing behavior. We can't hope to change genetically endowed traits of our patients, and we shouldn't even try beyond a limited extent. What we should do is realistically design treatment plans to make it as easy as possible for each patient to cooperate.
The article by Dischinger in this issue of JCO addresses the problem of poor compliance by turning a permissive Class II functional appliance into a fixed one that enlists the muscles continuously. There is no doubt that the Herbst appliance can treat Class II malocclusions effectively. But Dischinger shows us how to do it in combination with fixed appliance therapy, while retaining the good will and cooperation of the patient throughout treatment--no mean feat these days. An almost indestructible, cemented functional appliance will work for even the most sensitive Class II patient, because constant force is much less painful and disruptive than intermittent force, and much more predictable.
The development of orthodontic appliances that resist destruction and promote continuous use should be a high priority for our profession. Without them, large numbers of our patients will be unable to cooperate enough to insure superior treatment results.