The Challenge of Adult Orthodontics

There are some distinct differences between orthodontics for the adult and for the child. One of the more interesting ones is that adult orthodontics is often symptom related, whereas with the child we are largely dealing with signs. The difference between signs and symptoms is that a sign is something the practitioner can see, whereas a symptom is something that the patient can sense. With a child, one does not usually see periodontal disease or a temporomandibular joint problem. The functions of eating, breathing and speaking usually are able to be performed adequately by a child no matter how severe their malocclusion is. The child would have to have a seriously handicapping malocclusion before it interferes with one of the important oral functions. Of course, there are psychosocial aspects that must be considered as well as the physiological parameters. The psychosocial aspects include the reaction of others to the patient and the patient's reaction to himself, namely self-image.

The adult patient usually has a number of symptoms or they probably would not find themselves in your office. For example, if a 35-year-old female presented with a mild Class II division 1 malocclusion with good alignment, excellent periodontal health, no temporomandibular joint problem and pleasing esthetics, the chances are that you would not recommend treatment, because there were no symptoms. For a variety of reasons, based on the same signs, you would be very willing to treat a child with the same malocclusion. So, with the adult, diagnosis is really simpler than it is for a child. The diagnosis more or less "leaps out at you" and, sometimes, the diagnosis is even made by the patient. Treatment is sometimes more difficult for the adult, because it requires the combined expertise of a number of specialties, and growth is not on your side. Without growth and with some of the symptomatology that occurs, requiring other specialists, orthodontic treatment of adults can be very much more complex than treatment of the child.

One has to be very careful in dealing with adults to rule out psychological problems or neuroses. If an adult who comes to you with a rather minor orthodontic problem, is exceedingly anxious about it and has a heightened response when asked what they think is wrong with them, these same people may also have an exaggerated view of what orthodontics is going to do for them. Some of these patients can become "unhinged" very easily by what they would see as an unsatisfactory result. We also don't want to create "dental neurotics". If a patient has neglected their teeth over the years and now requires a great deal of periodontal therapy, orthodontics and fixed prosthesis, although they may have a casual interest in achieving optimal oral health, it is surprising how easily they can become neurotic about their oral cavity through overly zealous treatment.

Defining Adult Orthodontics

I would suggest, as an operational definition, that adult orthodontics is concerned with striking a balance between achieving optimal proximal and occlusal contact of the teeth, acceptable dentofacial esthetics, normal function, and reasonable stability. Of course, I am using a number of obfuscating words here on purpose. Optimal, acceptable, normal and reasonable are not very easy to

define. Up to the 1930's, orthodontists felt that they could achieve ideal occlusion, ideal facial esthetics, normal function and pretty much immutable stability in a large percentage of patients. It is only in the last 25 years that nearly all orthodontists accept the idea that these goals are sometimes mutually exclusive. For example, sometimes the placement of the lower incisors for optimal stability is incompatible with facial esthetics. Of course, sometimes the question is how can we achieve stability at all, particularly if there are periodontal problems with significant loss of bone.

Figure 1 is a typology of eight adult patient types. Adults can be arbitrarily divided into an occlusal harmony group and an occlusal disharmony group. With the child, we are talking largely about function-- mastication, speech, breathing. With the adult, we are more frequently concerned about physiological adaptation. A patient's occlusal disharmony may still be able to adapt physiologically, i.e. have no temporomandibular joint problems and no periodontal disorders.

In Figure 1, one of the cells depicts a situation in which a patient has occlusal harmony, acceptable dentofacial esthetics, good self image, and favorable function and physiological adaptation. In that cell, you would say that that adult patient obviously does not require treatment. If a patient has all these same characteristics with the exception that they have occlusal disharmony but with good physiological adaptation, the patient still probably does not require treatment. As you look at all eight cells, there are only three of them in which orthodontics would be part of the treatment plan. This typology points out that the decision-making process for the adult is very straightforward and based on essentially three parameters-- occlusal harmony, esthetics, and function or physiological adaptation. Based on these factors, you would decide which cell the patient is in.

Approach to Diagnosis

Strang said that "There is nothing complicated about making a diagnosis in orthodontia. From the moment one has detected a deviation from normal occlusion and so determines that there is malocclusion, the diagnosis is complete". Most of us were brought up on Strang's textbook and accepted his view of diagnosis. Diagnosis really wasn't a critical factor once you recognized a malocclusion, the rest was simply considered case analysis. This is what we could call the "classic approach" to diagnosis and treatment planning in orthodontics.

Then we entered a period we could call the "enlightened phase" in which it was realized that one had to determine at what level the orthodontic problem existed. Was it a dental problem or a skeletal problem? There was concern with the etiology of the problem and the belief that you had to know more than just recognizing a morphological deviation. We are now concerned with "overall diagnosis" which takes into consideration not only the oral health of the patient, but all of the psychosocial factors as well.

For those of us who were brought up on the classic approach to diagnosis and treatment planning, we basically knew classification or systematic description, we knew in a limited sense how to determine at what level the problem existed. We knew that etiology was important; we knew

that one had to set treatment objectives; that one had to generate a treatment plan; that one had to devise a mechanotherapy that would achieve the treatment objectives; that prognosis was important in forecasting; and that retention and stability had to be considered. We knew that all of these factors were important in overall diagnosis, but nonetheless, we usually went back to the Strang approach.

Problem-Oriented Decision-Making

What we suggest today is the system that has been popularized in medicine, the problem-oriented approach to the decision-making process. This consists of gathering an adequate data base-- history, oral examination and other diagnostic materials-- and performing a structural analysis of the standard orthodontic records. From these date, one generates a problem list which can be structured in a variety of ways. One of the ways is to list the most severe problem first and then each additional problem in descending order. One then produces a tentative treatment plan for each one of these problems. Sometimes, these treatment plans are mutually exclusive or interact poorly. So, the next step is to consider the compromises that are necessary and "therapeutic modifiability". In other words, how close to normal or ideal can we come with this patient? What is the modifiability of the dentofacial deformity?

An example of these adverse interactions or compromises, might be an anterior open bite and a posterior crossbite in an adult. The tentative treatment plan for the crossbite might be to expand the maxillary arch. The tentative treatment plan for the anterior open bite might be to close the open bite by decreasing lower anterior face height. These two plans are partially incompatible, so a compromise must be reached. The compromise tentative treatment plans are then synthesized into a unified treatment plan.

We further believe that one does not arrive at a final treatment plan until after the patient is under treatment, because the therapeutic modifiability can often only be tested by response. We call this therapeutic diagnosis. No matter how well you list the problems, defining them so clearly that the treatment plan is self-evident, and no matter how well you have designed the tentative treatment plans, no matter how well you considered the interactions and the compromises and the therapeutic modifiability-- one can't establish a final treatment plan until one has tested the treatment response and has made a therapeutic diagnosis.

There are five characteristics that must be examined in a structural analysis: 1) alignment, 2) profile and facial esthetics, 3) transverse dimension (crossbites) 4) anterposterior or sagittal (Angle classification) and 5) bite depth.

In recent years, we have become more sophisticated from a morphological standpoint with Andrews' Six Keys to Occlusion. Each one of these Six Keys fits into one of the 5 major characteristics. The Six Keys really should be thought of as six details of ideal occlusion. It should also be mentioned that Andrews' Six Keys do not necessarily apply to the therapeutic occlusion of the periodontist or fixed prosthodontist.

Quantifying the Problem

It is not enough simply to qualify the problem, to say for instance that there is an alignment problem. It is necessary to quantify the problem as well. Dr. Proffit and I suggested that it be done with a subjective rating scale (Fig. 2). We suggest that the orthodontist in his mind's eye use these definitions: 0 is ideal, with no deviations at all. 1 would be a slight problem, with a deviation from ideal which would not require treatment if this were the only characteristic involved. If the patient only had a slight alignment problem, the chances are he would not require treatment. However, if it is a moderate problem, then this deviation alone would justify treatment. 2 is slight to moderate, 3 is moderate, 4 is moderate to severe. 5 is a severe problem in which the patient is handicapped by the deviation. We have found that orthodontic postdoctoral students achieve a great deal of agreement with these subjective ratings in a very short period of time.

We have found that if one generates the problem list in this format, it is then easy to state a diagnosis in narrative form. Diagnosis in orthodontics requires the synthesis of manifold complex factors into a discrete list of problems, each one defined so clearly that the treatment plan is self-evident. I think that this is the key to adult orthodontics.

Lastly, I can't emphasize enough how important combined therapy is in adult orthodontics. In a child, one occasionally calls on another specialist; an oral surgeon to remove teeth, occasionally a periodontist. With the adult, consultation with another specialist isn't occasional. It is the rare adult whom one treats orthodontically without finding it necessary to collaborate with another specialist. This represents both the challenge and the excitement of adult orthodontics.