As most readers know, Dr. Ricketts passed away recently. In memory of one of the giants in the orthodontic profession, we continue with more insights from Dr. Ricketts in his extended interview with Dr. Larry White. We are honored to present these articles and share with the Ricketts' family, the orthodontic community and the world, the sadness of his loss and the joy of his life.

Part 4 of the Interview with Dr. Robert Ricketts, Interviewed by Dr. Larry White

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Read Part 6

LLW: Invisalign has animated the general public with their direct appeal for the use of clear plastic repositioning devices. Is this technology a real advancement or do you consider it a professional fad?

RMR: There was an old saying at the University of Illinois when I arrived there, now 56 years ago. It was, I’ll treat ‘em if you’ll finish ‘em.” It seemed as though treatment and finishing were separated. At that time, one tube, one bracket and an edgewise wire were simple, but the orthodontist needed to be a master “bender.” As I learned later, the gross correction was made by way of tie-backs, blocks on the wire and intraoral elastic traction. But finishing was a different story.

In those days, we gave lip service to molar rotation in the upper arch. We also did not recognize that its base, the lower, also needed generous rotation to the distal. It was almost mandatory with the technique to place spurs and tie-backs in order to prevent incisor flaring. This also was done with a small loop and tie-back with round wires in the aligning and leveling stages. This pulled forward on the buccal side and rotated molars mesially in both arches. Finishing meant working on these rotations and also torquing the anterior teeth in order to achieve normal inter-incisal angles. But in addition, the canines were squared far too much, as I see in retrospect.

It is no wonder that the previous statement emerged because it entailed much hard work. It was not uncommon to see final patients finished with one side in locked Class I and the other unfinished or toward an end to end. Being a student of occlusion, by 1950 I was assigned the job of finishing all of the problem (deadwood) patients in the clinic. I was also asked to develop a new department of “Occlusion and the TMJ” in the school as the first one ever.

In 1945 Dr. H. Kesling of La Porte, Indiana designed a rubber appliance to help in the “finishing” process. He called it the “positioner.” It was originally processed in black rubber. He started promoting its use at the first consultation. Later, embracing the Begg technique, he extracted in the 90% range. With the teeth mobile at treatment’s end, the patient was disciplined to wear the positioner.

Ultimately, lighter rubber was used, but still the tooth set-up in wax was conducted by laboratory technicians and was quite standardized. This was so much that standard positioners were pre-made commercially.

In the 1950s, Dr. P. Usted in Los Angeles attempted to treat patients with a series of set-ups and rubber appliances. The problem was compliance and sequences of change in the wax correction. I attempted to use improvement set-ups activated with extraoral traction. The results were discouraging.

With the set-ups, we had problems. In some patients the bite deepened, and in some the upper incisors spread. I eventually had the set-ups sent from the lab first in order that I could do the details and overtreatment built into the positioner together with “tucking” the canines. I sent the current version in for the final production. I eventually essentially discontinued positioners in favor of liberal overtreatment.

With buttons and elastic materials, Dr. Carl Cugino and Dr. Hito Surahiro developed an appliance to be placed in series on the teeth. This too did not reach great popularity. Therefore, the idea of the Invisalign had a history.

The attraction, as advertised, puts down fixed appliances and presents the idea that there is a certain computer magic in the set up. The question regarding that science looms up quite significantly to me. When the expense and appliance issues are taken into account, the idea of total fixed appliance avoidance is seen in a different light. This is especially true when studs may need to be bonded on the teeth for engagement of the appliance and these are fixed appliances.

I see the Invisalign as a source of minor movements and for details in a second phase after early treatment. Possibly it can fit into the functional posturing field, but it would seem to me that major structural problems need to be addressed first.

It is difficult to imagine maxillary orthopedics derived directly with that approach. The ultimate test will be the success in perfection of fit of the teeth.

As I have said before, there is an average of one new movement per year in the profession. It takes time for the masters to make their mistakes, as all pioneers must do. The value of a new movement takes at least a decade to find its rightful place.

LWW: Some orthodontic companies are trying to develop customized bracket and/or wire systems. Do you have any experience with these concepts, and what advantages would they offer orthodontists and their patients? What limitations do you think they have?

RMR: The idea of a customized bracket seems to be the avoidance of any wire manipulation. But there is no doubt that overtreatment is required. During the first five years of my career, I spent much time and great effort in the perfection of fit of the teeth. I then recalled about 300 patients to review the situation five years later. It was abundantly clear that overtreatment was mandatory. Without that knowledge, I wonder why customized brackets would be better than our “facile formula” or even as good.

Perhaps for the untrained dentist this would be an aid. Also, nature is kind in the end with her post treatment adjustments. But the treatment in the end entails orthopedics and overtreament and placing teeth in position to resist the forces that displaced them in the first place.

I cannot see a great advantage when the expense of these efforts is considered in the whole clinical scheme. Actually, it is sort of an embarrassment to many clinicians that they should be considered to be so inept.

LWW: Some clinicians have developed a reliance on articulated models and claim that his technique exceeds any other method of evaluating the occlusion. Do you have an opinion on this?

RMR: Orthodontic training with models trimmed in the habitual centric has been the monument in orthodontics from the start. Simon, in 1920, mounted the upper and built up plaster to represent the Frankfort Plane. He trimmed to the Orbitale Plane as a reference for the upper canine. The habitual occlusion was employed to fix the lower on the apparatus. At that time he believed that mandibular growth was controlled by mechanics.

The idea of different mounting for the lower to the upper emerged with the gnathologists. Led by B. B. McCullom, this originally was to be in the most retruded position or “terminal hinge.” When that position was proven to be inadvisable, it was advocated that the condyle be placed in the midmost, uppermost and distal-most position (the MUD position). Through other works, promulgated primarily by Dr. B. Jankelson, there then developed the idea of centric relation (CR). It was with the assumption of a “centered” condyle in the fossa. The theme then was that the fossa-centered condyle (relation) (CR) should coincide with the centric occlusion (CO), and it sounded scientific.

Very early in my career, however, I learned from the famous orthopedist, Dr. Arthur Steindler, that all joints are maintained by muscle. Therefore, I described a physiologic centric (PC) as a muscular-centric. Prior to that, we had discovered that the typical click in the joint was preceded by a condyle which was backward in the fossa and which had overridden the posterior ridge of the disc. We had, with a stethoscope, identified a lighter click on closing, usually within the last three mm in closing to habitual centric. This meant a total mandible dislocation and a stretched capsular ligament.

In order to identify this type, the dental community had adopted the term “sub-luxation.” This was because luxation is a complete dislocation. It is, however, a little like being “slightly” pregnant. The prefix “sub” means below of less than completely. In this sense, the “click” was a sign of minor dislocation of the whole mandible, because the condyle and mandible are not separate, but one unit.

For the reasons of variation and need for detail, for my entire career I routinely have taken tomographic x-rays of the joint. This was prior to and after orthodontic treatment. With these records and with examination of the patients and awareness, I never felt that mounting of patients would contribute to a treatment plan that was not already manifested in three-dimensional analysis as a starting base.

Some dear friends and colleagues have been very critical of my stand, but they have not convinced me of its merits. Some have said that it’s cheaper than having models trimmed and polished. That’s an argument, and I don’t take issue with it. My real problem is not mounting the upper but, rather, how the lower is registered and who does it before the mounting.

The old orthodontists pulled out the model for each adjustment. The unpolished model would get dirty with handling, so it was polished. With intraoral color photographs and with three-dimensional cephalometrics, that practice was discontinued. Therefore, there is no present need for polishing of models, as I see it, although they should be trained as ususal.

The physiologic centric is mostly synonymous with the habitual centric. In most patients, the clinician must look for the exception. As Posselt showed in the 1960s, a retruded contact position is normal. No joint functions at the terminus of a border movement. The final finish in our practice is in overtreated condition to permit “metapositioning” during retention. The argument for mounting may reappear in relapses when no joint x-rays or MRIs are available.

It has been suggested that with the three dimensional Newtom scanner, impressions may be eliminated. In that event the mounting becomes a moot point indeed.

The articulator is always used for the construction of the bio-template for the TMD patients. Here again, registration becomes an issue. Arguments are present regarding a “treatment position” for the construction.

In truth, I have an x-ray discipline with oriented tomographs when the articulator doesn’t agree with the x-ray. I do not trust the articulator, while others mistrust the x-ray.

LWW: The interest in functional appliances has not diminished and, in fact, seems to have grown over the past decade. Do you see this increased use as a favorable development?

RMR: Your question cannot be answered effectively in only a few words.

The first question is, “What do you mean by functional appliances?” The second implication is that function is associated with muscle, which also includes nerves. The third implication, by tradition, is that functionalism, associated with posturing, with the idea that mandibular growth is controlled by mechanics. Some appliances incorporate “shielding.” This is from the lower lip, the buccinator complex or from the tongue. Does the word activator imply activating muscle or growth or eruption of teeth or just what? The word bionator implies biology, which is good. Let’s look at the whole idea of the “functional approach.”

Angle, who taught many of the pioneers in the profession, was an archetype of the concept of functionalism. This was, indeed, the thought behind his classification. From dental jargon, the maxilla was considered to be “fixed” to the skull and the mandible function was against the “fixed” upper teeth. The upper molar was therefore considered to be the starting reference for diagnosis. If the mandible did not match the maxilla, it was thought to be due to a mandibular malfunction of some kind.

In the case of Class II, the mandible, by some type of function, was restrained, and hence a disto-occlusion was described. Thus, sleeping or leaning habits were condemned. If the condition was Class III, the mandible was over-stimulated and needed restraint. Therefore, an abnormal function was blamed for the malocclusion, and the target was the mandible.

For treatment, if malfunction was the cause, then correction of function was deemed to be the cure. All the early orthodontists reasoned that the condyle cartilage could be directed by orthodontic means. It was called “bite jumping,” used for correction of Class II. The idea was that forward positioning would make the condyle grow backward and thereby move the chin forward in a pure mechanical sense. Hence, ramps or incline planes were employed to direct the mandible to a forward position. No x-ray recordings were available. Consequently, speculations and assumptions dominated the field. When growth was deemed to be over or the severity was very extreme, the general consensus, prior to 1900, was to remove the first upper premolars and attempt to move the anterior segment backward. Extraoral traction was used to assist in that objective. The molars remained in Class II.

In Class III, the chin cup with extraoral traction was employed and if unsuccessful, lower first premolars were removed and the lower anterior segment was retracted leaving the molars in Class III.

In Class I, when the arches were crowded, it was convenient to remove four premolars and retract the canines first. This was the general belief as Angle entered the scene in 1877.

All this changed, however, with the discovery of intermaxillary traction in 1898. Together with the use of the labial bar in .045” wire (1.10 mm), which was called the expansion arch (or E Arch), Angle reasoned that now the mandible could be directed by the elastic pull. He changed to a non-extraction mode. Not only was the mandible to be stimulated, but the entire face was theorized to be enticed to grow around the expanded denture by way of functional stimulation. He had observed past normal post-treatment behavior in males particularly and assumed it to be caused by the therapy.

By the 1930s, when treatment was delayed for management of all the teeth at one time, relapses and trauma led the field to what I called the “first wave of surgery.” It was to retract the mandible by horizontal ramal cuts. This led to condyle neck cuts and then to vertical ramal cuts behind the entrance of the nerve. The whole story of surgical changes is a different issue. The point made, however, that in waiting too long, orthodontists were obliged to resort to surgery for maxillo-mandibular skeletal correction. In other words, this is orthopedic surgery.

Many Class III patients treated in the deciduous and early mixed dentition never need any more treatment. Functional changes would be implied, therefore, to be most successful in the very young patient.

My original research was to test the hypothesis of stimulated growth through the pull of elastics. I fortuitously was exposed to laminagraphy, the original tomograph machine. It was used with circular motion and was undistorted. The cuts produced brilliant images of the joint, as we made a head-holder and calculated the cuts. The original protocol turned out to be a five-year study.

Imagine our surprise when we compiled the findings. If the condyle growth direction was posterior, we expected to see the chin move forward. But instead of the chin moving forward (as revealed by the Y axis), the face developed more height or the axis opened as the chin moved downward and backward. In those patients studied who had greater forward chin behavior, the condyle (and ramus) grew more vertically and the mandible more square. This confused the entire profession.

Moreover, due to the dogma of the belief in constancy and genetics in the “pattern of growth,” the changes were interpreted at the time, by myself and peers, to be a natural growth variation and not influenced by the treatment.

Later, graduate students at Loma Linda University studied rotational behavior and found that after treatment two out of three stayed or closed back toward the normal. However, the other third kept on developing more vertically. Therefore, bite opening by mandibular rotation could go either direction after therapy. Now the pot really began to boil.

When the brilliant x-rays were available and they were exhibited, questions immediately arose. What happens when the joint clicks? What factors precede the click or are a genesis of the click? What is the behavior in event of the activator treatment? And what is the effect of elastics?

As the activator results of the 1950s were studied, it was determined that a combination of several factors contributed to the occlusal change. A slight posterior condyle inclination was detected. The whole lower arch was moved slightly forward. The maxillary molar was stabilized or prevented from moving forward its natural amount. In Class II Div 1 the upper incisor crowns were tipped downward and backward. A gross correction was made, but usually a detailed finish was not achieved. This was my explanation when asked in 1950.

In 1958 I lectured at the European Orthodontic Society and offered that explanation. At that meeting I met Peter Bimler and at that time, together with the “German School,” there was a belief in mandibular growth stimulation by Korkhaus and others. Louis Baume had reported on posterior growth stimulation in experimental animals. Bjork, at that time, was into his work on metal implants as markers for superimposing for growth study. Balter was then developing the Bionator, and Frankel was also working with his posturing methods.

I had discussions with Bimler at that meeting. He was working with cephalometry. I tried to explain my findings and met with opposition in the whole functional school. Further, I discussed the findings with Korkhaus. In the 1960s, Bimler then visited my office. In the 1970s Frankel also visited me. Posselt also came to visit, as well as Storey from Australia. Bjork had spent a week with me in 1956. I am saying all this to let the reader know that I had ample opportunities for communication on a personal basis. The early findings still stuck with me.

I wrote and lectured on growth being expressed against the muscular sling of the temporalis and the masseteric-internal pterygoid complex. Normally the glenoid fossa moved distally from the coronal suture axis. Our knowledge was still incomplete.

In 1963 Bjork reported his extreme variations in growth but misled the profession by not showing the behavior of the chin in the face in the same paper. In 1969 I visited his laboratory and was privileged to trace the patients he had reported, together with other types of conditions in his material. His extremes were syndromatic patients, but they clearly supported my original findings. The posterior growth of the condyle was associated with remarkably downward and backward chin behavior. The forward growing condyles, almost like idiopathic condylar hypertrophy, were characterized by forward chin behavior. I agreed not to use his material until he published it, almost anticlimactically, in 1969. Unfortunately, many still use his extremes as a brief for the stand that growth is unpredictable. What nonsense!

But growth is predictable in a reasonable manner! Of course, accidents and systemic diseases or acquired biologic deficiencies are not predictable. Also, iatrogenic insults are more than would be expected. As a spin-off of the major research effort with the computer from 1964 to 1969, it was found that the mandible bent forward with normal growth. This meant that a curve of growth was present. After two years of effort, a growth curve (or arc) was determined in which long-term growth could be predicted to a surprising accuracy.

In addition, this offered a new model for analysis of arch development and a new view of mechanisms for chin behavior in the face. It also shed new light on anchorage.

Problems of mandibular growth analysis came with the method of super-positioning. The Mandibular Plane had been employed formerly. However, research showed that males experienced enlargement or secondary growth around the symphysis below Protruberance Menti (Pm). Of further significance, the lower border of the gonial angle was shown to resorb as the gonial angle drifts on the growth arc.

With the use of Pm Point and X Point (formerly Xi Point) at the mandibulr foramen, a corpus axis was constructed. A condyle axis was drawn from X point to Point Condylion. Normal growth from several samples, showed a typical 0.6º forward bend per year or 6.0º in ten years. By using the internal structures, the behavior during treatment by various modalities could be compared. The differences were revealed by data or were shown in computer-generated composites.

The findings in 17 groups of patients treated with all kinds of forward posturing devices were composited. They showed that, during the advancing experience, the normal upward and forward ramus bend was eliminated as the condyle and ramus grew more posteriorly. However, in all groups, when records were available, it tended to return soon to the normal predicted shape and size.

It is not well known that in the same opening, bending behavior was seen in patients treated with vigorous elastics in the range of 200 grams per side. This behavior accounts for the false sense of correction commonly experienced and the relapse experienced. If the growth pattern comes in and supports the advancement, all is well. If it doesn’t, the clinician is faced with relapses and even potential condyle damage!

If a full cusp advancement was made in the appliance in one step, some patients adapted the mandible to a forward position of the condyle at the summit of the eminence. The treatment was spectacular but the condyle and canines flattened as the mandible rotated in that position for all its functions.

As the mandible was measured in vertical ramal height, less growth was registered in the vertical than normal. Thus the answer to your question is, “Yes, the mandible is altered and the direct distance from pogonion to condylion is increased. But very shortly thereafter, it relapses. It is for this reason that extensive overtreatment is recommended by activator or Herbst users. In the end, the movement is dental. Post treatment may witness some functional remodeling in the maxillary complex.

The Rest of the Story

But that is only half the story. By using the same method of study, the findings of cervical traction for high convexity Class II was compared to normal and to the posturing samples. It was found that the mandible bend was greater. Vertical ramal growth was also greater. In addition, careful measurement suggested the temporal bone did not move backward as much in the headgear group as in the untreated normal samples. This was verified in three composited groups.

This serves as an answer for favorable mandibular growth behavior and compensation for the vertical effects of the extruded upper molars. The findings also showed quite statistically significant maxillary skeletal change, which was permanent.

I also take issue with the labeling of forward mandibular posturing to be “functional.” It would seem to infer that other methods such as extraoral traction are non-functional. Another term is “orthopedics,” which functional users seem to claim. Our research shows that cervical traction, when employed as recommended, is the single most significant orthopedic appliance yet studied.

Some clinicians tend to employ methods in which the patient has no chance for non-compliance, and that treatment will be rapid. Certainly there is no argument that many children in our American culture do not want to comply. Even those, however, will need finishing appliances to achieve the quality of result the patient pays for. My view has been, since I tried five different times in my career to use advancing techniques--even in adults, and found them not as good as the Bioprogressive mechanics employed as I teach it. In my hands, extraoral traction is used before growth is finished. The quad-helix, utility arches, sectional mechanics with extraoral elastics and cortical anchorage and straight proximating wires is far more superior and trustworthy, as I found in my practice. I’m sorry if that doesn’t fit what people want to hear.