Round-table discussion: Systems versus basic principles in orthodontics

Round-table

discussion: Systems versus

basic principles in orthodontics WILLIAM

L.

Boston,

WILSON,

D.M.D.

(MODERATOR)

Mass.

DISCUSSORS: FRANE

P. BOWYER,

Director,

Ameriw

ALTON

W. and

Director-,

American. E.

Professor Sohool

D.D.S.,

Chairman, Board

of

TENN.

Orthodontics SEATTLE,

D.D.S.,

Chairman,

of Dentistry;

ENOXVILLE,

Department

SHEPARD, and

of

Board

MOORE,

Professor

EARL

D.D.S.,

WASH. of

University

orthodontics,

of Washington;

Orthodontics ST.

LOUIS,

Dlepartment

of

Secretary-Treasurer,

MO. Orthodontics, American

Washington

University

Association

of

Orthodontists JOHN Professor

R. THOMPSON, of

D.D.S.,

Orthodontics,

Northwestern

PAUL

V. REID,

Clinkal

Professor

aind Chairman

School

of Medicine,

University

of

D.D.S.,

CHICAGO,

ILL. lJniversity

PHILADELPHIS, of

Dental

School

PA. Department

of Pennsylvania;

of Orthod80ntics, Director,

Graduate

American

Board

Orthodontim

HUMPHREY : It is a pleasure to introduce the moderator and members of this discussion group. They were selected after much thought. When looking for a Imoderator, we felt that we could not find anyone who would fill the bill better than the man who is serving in this capacity this morning. He has a broad concept of our problems. It is now my pleasure to introduce Dr. William L. Wilson of Boston.

DR.

Presented dontists, presided

at the fifty-seventh Denver, Colorado, over this round-table

annual meeting of the American April 20, 1961. A.A.O. President discussion.

Association William R.

of OrthoHumphrey

251

Dr. Wilson: Thank you, Dr. Humphrey. f thmk it wouki 5i: aypropsiate at As time to have a few words about the program and something of the phi‘osophy of this entire meeting from the program chairman. Dr. Salzmann. DT. Salemann: The program speaks for i&elf. When Dr. Bnmphrey asked UL’ to be his program chairman, I wrote him a detailed letter setting forth ms belief that it was high time we gave thought to a re-evaluation of basic ortho.?ontic principles rather than to systems of appliances. I received a letter from 3~. Humphrey stating that he had read, reread, and studied my letter. Iie doneluded with the following short sentence : ‘LYou are still my program chair~nm." Both Dr. Humphrey and Dr. Carman, the general chairman of this meetyug, gave me a free hand, and there were times when I wished they had not iione so. When I approached Dr. Wilson on the subject of this morning’s sesGon: he came forth with a number of suggest,ions. Then, with Dr. Humphrey3 Approval, I wrote him and said: “You know, you are going to be the modtiyator.” What you hear this morning was really outlined up in New England. There was a tremendous amount of work involved in bringing this session before you today. It was done by Dr. Wilson. He invited the participants ant1 tvorked for two pears on this morning’s program. I wish to thank Dr. Wilsor: arid the participants for their cooperation.. Nom I shall turn the session over to 3r. Wilson. Dr. JV&on: Thank you, Dr. Salzmann. Before I introduce the members of !.his group. I would like to discuss the reason for this session and then say a .ew words about the nature and purpose of this discussion. I am sure t~hat each 32 you must share with us a concern for 0u.r specialty at the present t’ime bcxuse of the strong cleava,ges in our orthodo!ltic concepts. Some of these clearqes have been related to appliance systems. There are many reasons for t’lzis, ?iot the least of which has been the authoritarian nature of our meetings. We llave had the lecturer-audience, teaeher-disciple, leader-follower relationshil-i lchich, in itself, leaves lit.tle room for discussion and questioning. We have felt the need for some free and open discussion, and yet if we “oak back at previous attempts we find that they produced some very undesirable results. Years after the smoke had settled, those discussions f reqnently served
Panel discussion

certain instances. Another group has believed in radiotherapy

25 3

and chemotherapy rather than in any surgical excision. There was sach a strong cleavage between these two groups that they found it difficult to communicate. A few years ago the American Cancer Society held a meeting at which there was an open discussion., such as this one, in which men with divergent opinions brought their opinions to the platform and expressed them freely and without rancor. Mind you, th.ese men were not dealing with the alignment of teeth ; they were dealing with life and death. As a result of this open discussion, there is now an integrated effort to combine chemotherapy with surgery, and during the last three years there has been a noticeable lessening of fatalities in cancer treatment. We, too, I believe, can profit from a fresh approach through proper group dynamics. Some have deplored this new attempt because they are concerned with the inherent dangers. It is our feeling and the feeling of Dr. Salzmann, our program chairman, that we as a profession have reached a point where now we can do this. This morning will witness our attempt in this direction. I wish to say just a few words now about the personnel of this panel and about the procedure to be followed. In selecting o,ur personnel, it was important to pick men who were outstanding because they were leaders in their field and not because of any particular affiliation that they might have. It was important to pick men with different opinions and strong convictions. More important, we had to pick men who were willing to express their opinions and cross-criticisms openly a.nd freely. We had to pick men who were willing to seek out what was right and not wh.o was right; who were willing to criticize not merely for criticism’s sake, who would not ask questions to embarrass another or to inflate their own egos, who would be willing to sit down and reason but not rationalize, who would not substitute feeling for thinking or emotion for logic. Men of this type have been selected to participate in this round-table discussion. There is no need to relate their histories or their backgrounds; these are well known.. We have Dr. Paul Reid, Dr. Earl Shepard, Dr. Alton Moore, Dr. John Thompson, and Dr. Frank Bowyer. At the outset, I want to assure you of one thing: I am sure that as a result of this discussion there is not a man here at this talble who can or will emerge, or even desire to emerge, the superior orthodontist . We are going to have three ten-minute reports by Dr. Bowyer, Dr. Shepard, and Dr. Moore, who will explore some of the basic a,pproaehes to treatment as they see it. These three reports will be followed by three five-minute evaluations and short dliscussions by Dr. Reid and Dr. Thompson. This is being used as an introductory mechanism, and immediately thereafter this table will then be thrown into an unrehearsed open-ended round-table discussion in which all six men will become equal partners in a free exchange of opinions. I now take pleasure in calling on Dr. Bowyer. Dr. Bowyer: I sincerely appreciate the privilege of participating in this discussion. I well realize that I am here merely as the representative of the many capable and conscientious orthodontists throughout this nation who successfully

‘3.54 we

dmp,i~ici~ib !abidinguai

2,:. .,‘. ‘0, tiLVdVi”LtcO

.~ssoc~~~tio~~b oj O~~ihutdorhCisis appiiallee

proced~~res

ill

their

Afwik

~JiXctb3S.

i

%&ure

&a~,

1962

r.q

iellow members of the panel, and this audience that it is my intention to participate openly and freely this morning as we explore some of the controversial issues that confront our profession. With reference to this morning’s session, the of&&l program states: ‘. There xs Ytrong cleavage at present in orthotlont,ic concepts, causing different and opposing opinions regarding objectives and treatment planning. Much of this controversy has its origin in the rigid adherence to appliance Xystems. The purpose of this discussion is to investigate the Basic Primiples of orthodontic treatment ds related to appl.iance Systems.” To accomplish the objectives of this discussion, we must agree and willingl;v admit that the biologic principles of growth and development and the biologic principles which make tooth movement possible are the true “basic principles” of orthodontics. We must also agree that these ’ ’ basic biologic principles ’ ’ are af far greater significance than any “mechanical system, ” whichever it may be. We must further agree that it is not in keepin g with sound professiona. judgment to have blind acceptance of a “diagnostic system’ ’ or “treatment system’ ’ &ablished by an individual to suit his personal likes or dislikes without due p’egard for IL basic biologic principles” as they relate to each individual patient. How retarded our progress would have been these past fifty years if there had been only development of appliance systems and diagnost,ie and treatment systems, without the outstanding biologic research of Ketcham, Hellman, Todd, Oppenheim, Breitner, Gottleib, Beck, and others ! How wonderful it is that in this age of confused thinking we have outstanding men in the field of biologic Ihesearch (such as our Nershon Lecturer, Dr. Louis Banme) who constantly remind ::s that a thorough understanding of the underlying basic principles of skeletal, muscular, and dental growth is prerequisite to successful orthodontic therapy. I am sure that all of us are cognizant of biologic principles, regardless of r,ho mechanical, diagnostic, or treatment systems that we use, However, are we properly relating these principles to our systems? That is the vital quest.ion. At this point, I would like to quote briefly from the writings of two authorit,led to show how their findings are related to t,he basic rationale of the labiolingual philosophy of diagnosis and treatment. Nile Hellman wrote as follows: I cling to a technique that is reducible to the simplest expedients. I ha.ve never tried to rJroduee rapid toot,h movement, but I am always aiming at shortening the periods of ortho.!ontie procedure. In my estimation, an appliance to be the least llarmful must, to begin witll, exert slight effect,s upon vital tissues. Then, it must also alloTT time betrveen these periods of &restive action, so as to enable the tissue to regenerate. Then also, an appliance accomplishes :riore and does less harm during periods of normal growth and development, than during @ads of rest.

I now quote from the late Albin

Oppenhcim :

In the use of strong forces, the peridontal membrane becomes crushed, and its nourishfacilities cut down. As a consequence, undermining resorption sets in from various sides, riot only in the direction of the intended movement. The resorption or loss of bone is therefore uot limited or controlled. To avoid these occurrences we have so far only one mea,ns, and that is to avoid too great or too long protracted compression of the p&don&l membrane. Mp histological evidence would seem to prove these points: (1) The application of light forces is correct and preferable in orthodontics. (2) Our ~vorlr should be performed so as to give ment

Pane L discussion

255

nature ample time for compensa.tory formation of osteophytes. (3) Only light forces are able to produce an abundance of the primary osteoclasts which alone can be considered our real helpers. They alone work without creating too great damage, if any at all. These primary osteoclasts are the principal factors in bringing about all the marvelous and revolutionary changes without clouding the prospects for the future.

In. his memorable lecture on Monday morning, Dr. Baume made the statement, substantiated by biologic research, that the condylar cartilages definitely direct the forward growth of the mandible. He further stated that the endochondral growth centers can be stimulated by orthodontic treatment procedures. In personal conversation after his lecture, he assured me that the Oliver occlusal guide plane was a most effective means of stimulating forward development of the m,andible, especially if used in the early years of the deciduous and mixed dentitions. In. relating basic biologic principles to the labiolingual philosophy of diagnosis and treatment, we firmly believe that early and intermittent treatment has a definite place in orthodontic therapy. It is my opinion that it is through this appro,ach that our greatest contribution to orthodontic therapy is to be made. Let us for a moment apply common logic. When we notice a definite malocclusion in the mixed dentition, or even in the complete deciduous dentition, and we know that the dentition will continue to proceed along the lines of abnormal development because the existing malocclusion presents factors that are defini.tely inhibitory to normal development, is it not wise to treat the case immediately? The fundamental purpose is to remove the inhibitory factors, restore the particular case to normal for that patient’s age, and give growth and development a chance to continue normally. I think that in such a case treatment should be started immediately, and I believe that my opinion is strongly substantiated by those who relate their diagnostic and treatment systems to basic biologic principles, regardless of the specific appliances which they use. Bear in mind that in the treatment of these cases I do not refer to positive tooth positioning to a supposedly predetermined arch form. Rather, I refer to treatment that stimulates and directs segments of arches, complete arches, or individual teeth into paths of normal growth and development. I refer to trea.tment .which allows individual teeth spontaneously to assume normal position as various inhibitory factors are removed. This action can take place very nicely with labiolingual procedures, for all the individual teeth are free except for th.e six-year molars, which are banded for anchorage. I refer to treatment in which appliances are used at intervals throughout the patient’s natural growth period.s to produce changes when they can and should be produced, with frequent periods during which appliances are removed to permit normal adaptation of the tissues to the new positions of the teeth. With this type of treatment, we are not only helping to correct a definite malocclusion which existed at an early age, but we are helping to prevent that existing malocclusion from interfering with normal growth and development and thus preventing it from becoming progressively more complicated. If we fail to take advantage of intermittent treatment of deciduous and mixed dentition cases, we refuse to approach the ultimate goal of all medicine and dentistry-prevention.

At this point, I would like to show a ease of Class II, Division 1 malucclusiorl in the mixed dentition in which, in my opinion, treatment is definit,ely indicated. Fig. 1 shows the full-face and profile views. I call attention to the gross facial distortion which involves t,he lower lip resting lingual to the upper incisors.

Fig.

1.

Fig.

2.

i also call attention to the obvious impairment or‘ dental function and the 1~ desirable esthetic position of the upper anterior teeth. I would certainly suggest a stage of treatment for this patient at this time. My treatment plan would be to stimulate lateral development in the constricted anterior area of the maxillary arch (Fig. 2) to allow forward positioning of the mandible to a Class I rela. tionship by the use of an occlusal guide plane and to retract the protruding maxillary anterior teeth with gentle Class II elastics. The over-all objective of this stage of treatment would be to improve function and esthetics and to reorient the facial musculature in a proper manner, thereby diverting a very abnormal developmental pattern to a more normal pattern. I usually anticipate approximately twelve months for this st,age of active treatment. The occlusal guide plane is usually required for approximately six months, but in many cases it may be used less than six months. Fig. 3 shows anterior and lat,eral views of the labiolingual. appliance and i 11~:ocelusal guide plane in place. You will notice that the patient is attempting

Panel discussion

2 57

to occlude in his original bite position, which. he cannot do because of the oc.. clusal guide plane. Fig. 4, A shows the anterior overjet prior to placement of the occlusal guide plane. In Fig. 4, B note how the patient is immediately guided to a new predetermined anterior and vertical position by the proper angular construction of the occlusal guide plane.

F’ig.

3.

Fig.

4

Class II elastics are used, but they are nolt used to move the mandible forward. This is done entirely by the occlusal guide plane. The very gentle Class II elastic is used for lingual movement of the upper incisors only. Consequently, th.ere -is no severe traction on the mandibular anchorage and no tendency whatsoever to disrupt it. Now I will show a completed case treated. by this procedure. Fig. 5 shows Ml-fa,ce and profile views and an intraoral profile view prior to treatment. I

call attention t,o the unfavorable skeletal and rnaseulay balance: ol this face, Fig. 6 shows anterior and right and left lateral views of the original model. Fig. 7 shows the profile view at, the completion of the twelve-month first stage of

Panel discussion

2 59

treatment. 1 now call attention to the nice facial skeletal and muscular balance. Fig. 8 shows anterior and right and left posterior intra.oral views, and Fig. 9 shows anterior and right and left lateral views of record models at the completion of the first stage of treatment. Yen will notice from the intraoral photographc; and record models tha.t this case is now in Class I relationship, with a normal overjet and overbite. From this point to the completion of treatment, only a Hawley type of removable retainer and a simple labiolingual appliance with gentle Class II elastics were used at intermittent stages. Fig. 10 shows anterior and right and left posterior intraoral views of the case two years out of retent,ion. Fig. 11 shows the profile view of a well-balanced face two years out of retention.

Fig.

7.

Fig.

8.

I am well aware that there are those who doubt. t,ne merits and many of rantages claimed for the labiolingual a.ppliances. Row quickly their dou lid be removed if they were honcstlp milling to Rtudy the fundament,als ;

Fig.

Y,

forth painstaking efforts and thoi@t, in maswrinp criticism of the la.biolingaal methods of treatment lerstand these principles and a lack of knowledge ?ry highly regarded school of thought in our specialty

the iri~iclpleai lloss stems from a failure of operative techniq today employs the ba

Panel discussion

26 1

principles of the labiolingual technique to some degree. My honest conviction is that the furt,her one departs from it, invariably the further he departs from the most dependable manner in which appliances may be used.

Fig.

11.

In summarizing, let me say that those of us who use the labiolingual appliances, with their numerous auxiliary spring attachments and the occlusal guide plane, do so beca,use we sincerely and conscientiously believe that they, more than any others, uphold the classic standards of the ideal appliance. We believe in their efficiency because with them we can obtain any basic tooth movement and we feel that we can do so in keeping with biologic principles. In adldition to individual tooth movement, we can direct the growth of entire segments or complete arches, and we can do this also in keeping with basic biologic principles. We can treat permanent dentitions with the labiolingual appliances as capably as with any other appliance, and we have a decided advanta.ge in the treatment of deciduous- and mixed-dentition cases. I would like to leave you with this pa.rting thought: Orthodontics has suffered immeasurably from a constant pendulum-like swinging from one treatment to another. We often admire the end result gained by a particular orthodontist using a certain appliance but too often we forget the years of experience and trial-and-error diagnosis, accompanied by a natural inherent knowledge, which serve to distinguish one orthodontist’s services from the services rendered by another. Many capable orthodoritists are unintentionally guilty of causing much grief t,o younger or less capable orthodontists by selling them on some particular appliance or treatment procedure and modestly not stressing their own personal ability to manipulate the appliance or their thorough understanding of their particular treatment procedures. Liet us cautiously realize that, like the surgeon’s scalpel or the artist’s brush, any appliance is but a tool .with which to work. Therefore, let us continually

for personal perjection with whatever diagnostic and treatment SyStem we use, and let us be ever cognizant of the importance of relating them to basic biologic principles, for it is only in this way that the science of orthodont,ies, which is much more important than any individual or any system, ca.n yield its greatest benefits to mankind. Dr. Wilson: Thalk you, Dr. Bowyer. I now call on Dr. Moore. Dr. Moore: Systems arise from man’s desire for order in approaching problems that have common characteristics and lend themselves to classification and similar solutions, Without a systematic approach to our orthodontic problems, orthodontic education and practice would bog down in the mire of details and facts that make up the orthodontist’s armamentarium. By assembling related data and criteria from the sciences which comprise the b,asis for orthodontics, we develop the basic principles that govern the practice of our spec.ialty. For example, Angle’s introduction of a universally accepted classification of malocclusion was a milestone in bringing order out of chaos. It gave orthodontists a common meeting ground on which they could approach their problems in a systematic manner. Classification became one of the basic tools from which arose many of the principles that govern our thinking today. Systems, in themselves, are not undesirable when they are applied intelligently to the problems of orthodontics. When a system is blindly followed and dictates the thinking of t,he operator, however, then the orthodontist’s potential ability is limited by the rigidity of the dogma that comprises the system. Is an orthodontic appliance, in itself, a “system”! Basically, an orthodontic appliance is a mechanism for applying controlled forces to the periodontium to initiate biologic changes that will. result in controlled tooth movement and influence the dental-facial growth pattern. In itself, then, an appliance is not a system. The basic principles of an orthodontic appliance whieh underlie the component parts and their manipulation lend themselves to a syst,ematic analysis for purposes of education and application. This, combined with a consideration of the basic biologic principles of orthodontics, may be said to comprise an appliance system. Such an a.ppliance system, applied intelligently, is desirable because it facilitates treatment procedures. If, however, the operator blindly follows a prescribed routine in the application of such an appliance system, without regard for the infinite variations that exist between patients and their grossly similar malocclusions, then the system in some instances can lead only to confusion and failure. Appliance systems, in themselves, are not bad if they are founded upon the basic principles that govern the art and science of orthodontics and are then applied with intelligence. I have been assigned the task of discussing the edgewise appliance in relation to systems and basic principles. This would be a formidable task if I attempted to include all the various ways in which this appliance is being used today. Needless to say, it would also be most confusing. It can be said, however, that the edgewise appliance is one which has t,he potential for controlling the position, in all planes of space, of each tooth in the dental arch. The intelligent application of these controlled forces must be founded upon t,he basic principles that govern orthodontic treatment. strive

Panel discussion

2 63

What are these basic principles that govern the rational application of orthodontic treatment procedures in the Class II malocclusion? This discussion must be sketchy, because of time limitations. Basically, we must evaluate the following before a rational treatment plan can be formulated, regardless of the appliance used : 1. 2. 3. 4. 5. 6.

The The The The The The

physiologic age of the patient. growth potenti.al of the patient. skeletal pattern of the patient. muscular and -functional pattern. adequacy or inadequacy of the dental arch length. incisor’s relationship to the facial profile.

T:his evaluation will determine our treatment objectives. If we are dealing with a Class II malocclusion in the mixed dentition which may be classified as borderline with respect to extraction, we may summarize our objectives as follows : 1. Establish a Class I molar relationship. 2. Maintain or, if desirable, gain mandibular arch length. 3. Establish a maxillary and mandibular incisor relationship in harmony with the facial type and profile. 4. Establish the vertical relationship of the denture within normal limits. A case involving a Class II mixed-dentition malocclusion is presented illustrate the appbance needed to reach the above-stated objectives.

to

This is the case of a boy who was 8 years of age at the time the original records were made. He had a Class II, Division 1 malocclusion with shortening of mandibular arch length and a retrognathic skeletal pattern, as seen from the cephalometric headfilm and facial photographs (Figs. 1, A, 2, 3, A, 4, 8, 5, a, 6, 8, and 7, a). The patient’s dental and physiologic age seemed to be correlated with his chronological age. His skeletal pattern, as revealed by the cephalometric film, indicated that he did not have a very favorable growth potential from the standpoint of pattern. However, a considerable amount of growth could be expected in a patient of this age, The patient had an anterior open-bite, which would suggest the presence of abnormal tongue function. A. treatment plan was outlined which would work toward the objectives that were previously :mentioned with regard to Class II malocclusion in the mixed dentition. A maxillary Kloehn type of face-bow and a cervical strap were placed in order to guide the occlusion into a Class I molar’relationship. A mandibular lingual arch with four incisor bands and a light labial arch were used to correct the deficiency in mandibular arch length that was present on the original casts. This was the only appliance used to achieve the results shown in Figs. 1, B, 2, B, 2, B, 3, B, 4, B, 5, B, 6, B, and 7, B. It will be noted that the second casts show four maxillary incisor bands which had been placed, just before these casts were made for the purpose of controlling the maxillary incisor positions. These bands had not been used to effect the change in incisor relationship that is evident in Pig. 6, A and B. The maxillary incisal changes noted were brought about through the forces of occlusion and the change in interarch relationship of the teeth effected by the maxillary headgear and the mandibular appliance. Fig. 2, A and B illustrates the changes that have taken place in the three-year period of time from a cephalometric point of view. Fig. 2, A is oriented with the center of sella turciea registered and the sella-nasion lines superimposed. This illustrates a f:avorable change in the patient’s skeletal pattern. Fig. 2, B shows the amount of mandibular growth that has occurred and the slight forward tipping of the mandibular incisors,

Fig.

1.

:

_._.-’

Fig.

2.

The future treatment of this case calls for depression of the maxillary incisors througil the use of a, spur off the Rloehn faee-bow against the labial maxillary arch wire. In another year the case will be re-evaluated to determine the desirability of further orthodontic therapy. Some may question whether this case should have been treated without the removal of four premolars, but I personally feel that this decision cannot be made until we are able to assess what effect future growth may have on the patient’s facial and skeletal pattern. I am not

T~olume Nmmber

48 4

happy with the esthetic results achieved as shown convinced that any other type of treatment plan a better response for this particular patient.

Panel

discussion

by the progress photographs, instigated at this age would

2 6 5

Fig.

3.

Fig.

4.

Fig.

5.

Fig.

6.

Fig.

7.

but I am not have elicited

If the problem at hand is a Class II malocclusion in the early permanent dent-ition, then the objectives are the same as those outlined for the mixed dentition. The amount of appliance control necessary to resch these objectives is

irrweased, however, because the peak rate o.i developmor~1, 01’ I;& denture has slowed down materially, and we are dealing with a denture in its later stages of growth. A case of Class II malocclusion in the early permanent dent,ition is psented

to illustrate

the riced

fog inmmed

appliance

B’ig.

3.

Vig.

9.

control

wt this

ape.

Division 1 malocclusion with some The patient, a 13.year-old boy, had a Class II, crowding of the lower incisor segment. After the case was evalua.ted on the ba’sis of the criteria previously outlined, it was, decided that a full mandibular and maxillary edgewise appliance should be used in order to effect the desirable denture changes (Figs. 8 to 14). It was anticipated that this patient would have further growth, and that this would be advantageous to the treatment plan. The mandibular incisors were depressed and the molars elevated, as shown in Fig. 9, B. The maxillary incisors were moved bodily in a posterior direction by utilizati.on of the space available in the maxillary arch and by posterior tipping of the maxillary molars. Throughout treatment the patient wore a cervical headgear to the mandibular arch wire, which controlled the anteroposterior position of the mandibular arch during the posterior retraction of the maxillary teeth by intermaxillary elastic traction.

Fir.

10.

Fig.

1 L.

12.

Fig.

18.

Fig.

14.

l’his patterns

treatment; has resulted as well as in his facial

in a marked pattern.

improvement

in the patient’s

skeletal

and

denture

When the problem is a Class II malocclusion that may be classified as borderline with regard to extraction, and the patient is beyond the age at which any appreciable facial growth can be expected, then our treatment objectives must be altered as follows: 1. Without growth, maxillary molars are best left in their presenting anteroposterior position. Thus, extraction in. t,he maxillary arch becomes necessary to permit retraetion of the maxillary incisors. 2. In order to maintain mandibular incisors in their presenting anteroposterior position or to retract them if retraction is deemed necessary, extraction in the mandibular arch becomes a desirable procedure. This makes it possible to apply differential anchorage values which would permit the forward movement of the mandibular molars to establish a Class I molar relationship while at the same time retracting the maxillary incisor segment. 3. Proper control of the appliance ensures that maxillary and mandibular incisor inclination and position will be established at the most desirable relationship for stability and facial esthetics. To summarize this discussion briefly, it might be reiterated that appliance systems, in themselves, are not undesirable if they are founded upon the basic principles that govern the art and science of orthodontics and are applied intelligently. Llr. IV&on: Thank you, Dr. Moore. I now cali on Dr. Shepard. Dr. Sheparcl: It is a sign of the times, certainly, that we can participate in a discussion with fellow orthodontists of various appliance leanings to prove that the results of orthodontic therapy t,ranscend .the commonplace so-called mechanics and indicate that any one of several methods need but be understood and applied. The cases of bilateral distoclusion with labioversion of the maxillary anterior teeth (Class II, Division 1) which I shall present are unusual only in that these identical malocclusions occurred in identical twins. The patients were 13.year-old with labioversion of the maxillary The posterior segments appeared severe overbite (Figs. 5 and 6).

boys of German ancestry who had bilateral distocl&ion anterior teeth (Class II, Division 1) ; Figs. 1, 2, 3, and 4. to be in bilateral mesioversion, and there was a moderately The cause of the malocclusions Teas not known. There was

Volume Number

48 4

Panel discussion

269

no history of habits. Examination of the mouths of both parents revealed no evidence of similar malocclusion. The faces of the patients showed a rather unusual hypertrophy of the complex of facial musculature involving probably the orbicularis oris, buc.cinator, caninus, and quadratus labii inferioris muscles (Figs. 7 and 8). The treatment plan called for (1) correction of the bilateral mesioversion, (2) alignment of the maxillary anterior teeth, and (3) reduction of the abnormal overbite.

Fig.

3.

Fig.

Fig.

5.

Fig.

6.

4.

All appliances were made of l-8/8 chrome alloy, joined by means of spot-welding and soldering with 14R gold solder. Primary anchorage was secured by banding the maxillary and mandibular first permanent molars with seamless preformed chrome alloy bands. Lingual arches, 0.036 inch, were soldered to the lingual surfaces of the molar bands, and 0.025 inch embrasure extensions were fitted into the embrasures between the right and left first premolars land canines. Round buccal tubes (0.036 inch, inner diameter) were soldered to the buccal surfaces of the molar bands; 0.025 inch hooks were added to the buccal surfaces of the mandibular buccal tubes to fa,cilitate the application of elastic bands. The maxillary buccal tubes were adjusted during soldering, so as to produce an intrusive force through the twin-wire labial arch to the anterior teeth. The maxillary central and lateral incisors were banded, using 0.075 inch twin-tie brackets. A twin-wire labial arch with hooks was utilized. The patients were seen at approximately four-week intervals. Four weeks after the appliance was inserted, Class 11 intermaxillary traction (I/ inch latex, 1Ys ounces) was begun.

ISesponse t,o were removed As the incisors were lary lingual threaded on

treatment was satisfactory. At the end of six months of treatment all appliances for caries check and prophylaxis. bite leas opening satisfactorily and the !ahio-irrcisal edges of the mandibular beginning to occlude with the lingual edges of the maxillary incisors, the maxilarch was removed. At this time 3/ inch 0.008 by 0.032 inch coil springs mere the end sections of the twin-mire labial arch. After t,he midsection was secured

Fig.

8.

into the brackets, the coil springs ~eie activated by compressing then& q+inat the an6erJ.v~ portions of the buccal tubes and crimping the end section with a pair of Young’s pliWS anterior to the coil spring. Class II intermaxillary traction of 3 ounces was used for Six months. At this time the coil springs were removed, and a flat 0.010 by 0.022 inch midsection lvas locked into place by crimping the end sections in the bueeal tubes. After two months the maxillary molar bands were removed, a flat anterior wire being secured to the anterior brackets, and Hawley-type retainers were constructed. The mandibular appliance was removed. The length of active treatment, was fourteen months. The maxillary Hawley-type retainers were horn full time for six months and half time for one year. No mandibular retention was employed.

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is my opinion that good stable functional as qrell as anatomic occlusions were estabAll the more unusual was the exact. timetable adherence to both treatment regimes 9 to 14). Observation of posttreatment findings in the unusual sequence of cases led me to conclude that satisfactory results were ohtained with a minimum of mechanotherapy in a comparatively short time. lished. (Figs.

Fig.

Fig.

9.

Fig.

11.

Fig.

Fig.

13.

Fig.

14.

10

12.

The denture records of these patients shon that each boy has a. well-retuned normal occlusion two years out of retention. The facial records reveal the most unusual congenital facial contour with little true improvement rsthetically (Figs. 35 and lf;\.

Dr. Wilson: Thank you, Dr. dhepard. The program from this point tin :s unrehearsed. Your moderator knows no more than you do what Dr. Reid’s remarks are going to be. I take pleasure in calling on Dr. Reid. Dr. Reid: I want to express my pleasure at being on this panel. I want w make some comments about these case reports. Inasmuch as the title of this morning’s presentation is ILSystems Versus Basic Principles in Orthodontics, ” I would like to comment first on your remarks, Dr. Moore. I think that you stated the case for systems very adequately. Yen pointed ont that, so long as these systems are used sensibly and with recognition of the infinite variety of problems that arise with each specific case, there cannot be any argument about Them. That much, I think, is stated perfectly.

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YOU cite as an example our use of the Ang1.e classification and our universal acceptance of it in spite of th.e fact that it is primarily a convenience which allows US to communicate with. each other at meetings such as this and in the literature. We recognize its lack of specificity. In other words, the Angle classification does not always describe a case perfectly. Yet we recognize that and accept it, and we use it. Your remark that we have to have this in teaching is important. Personally, I feel that the labiolingual technique is the most exacting and the most difficult to teach. It is also a most rewarding technique when it is used the way that Dr. Bowyer uses it and when it is -used with the variations employed by Dr. Wilson and with the success that he achieves. The labiolingual technique does not lend itself to systematic teaching. As a result, there is much empiricism in it, and teachers are less likely to teach it because we do not teach it as systematically as we should be able to. AS for the case reports, I think that they were very well chosen for the purpos#e of this morning’s discussion. First of all, they represented the work of three men with varying viewpoints. Using three different approaches, all three men achieved success by different routes. The cases were presented in a matterof-fact way. I do not think that anyone tried to influence the audience or to impress us with the superiority of his approach. Dr. Moore showed two cases in which he used an approach dictated by the particular needs of each case; 1 am sure that if he had shown a dozen Class II cases I would have been able to make the same remarks. Th.e case that Dr. Bowyer showed was similar to Dr. Moore’s first case. A patient of the same dental age and with the same general type of malocclusion was treated with a guide plane as one of the adjuncts. To some, the guide plane is or has been a strange and unfamiliar appliance, but after Professor Baume’s remarks on Monday I am sure that there is a lot more curiosity about it. I think Dr. Bowyer used intermaxillary elastics rather than extraoral traction; yet I would like to see brought out later this morning that there really is not too much difference in Dr. Bowyer’s and Dr. Moore’s approaches to the same problem. Both were removing interferences to mandibular growth. The cases that Dr. Shepard showed are unique because they involved identical twins. Certainly, one thing was demonstrated very cl-early-that identical treatment achieved identical, excellent results. It seemed, at least from the pictures, that treatment was uneventful and that it progressed the same in both cases. At the same time, these cases posed a q.uestion, at least to me. Since we know that treatment does not always progress along that same smooth, uneventful path in cases that may be just as similar as the two that Dr. Shepard showed, I womler whether we do not sometimes completely overlook the genetic and slight the environ-mental factors because of too much reliance on a systematic approach to our mechanical therapy and thus fail to get that same uneventful success. There were some things that the three clinicians’ reports did not prove. Obviously, they did not all discuss treatment planning for the same case, and obviou.sly each could not have treated the same case from a different approach.

Consequently, there is no PGO~ for argument about 8 specific case, and tilat il;: very much to the credit of this type of discussion. The other thing that the case yeports did not bring out was the limitations that any of the appliance systems might have. Such limitations certainly exist; if they did not, there would be a Lot less interest in the new techniques when they appear. Dr. Bowyer’s case report did not show one of the limitations probably inherent in the labiolingual technique, namely, that it does not have the perfect toot,h control that the edgewise appliance has. The permanent-dentition case reported by Dr. Moore did not involve too mu& of a. problem with respect to the space requirements of the particular appliance, and in Dr. Moore’s first, case he did borrow from the labiolingual technique; t,hus, it seems to me that he failed to show the limitations in the edgewise technique to a deciduous- or a mixed-dentition ease that needs more extensive treatment. Dr. Shepard’s twin cases did not reveal our lack of control in root torque, among other things. In general, however, I think t,he case reports served excellently as a basis ior discussion, and there is plenty to discuss. Dr. Wilson: Thank you! Dr. Iieid. DY. Thompson: I certainly must agree with your remarks, Dr. Iteid, pertaining to the way l>r. Moore presented the basic material, systems, and appliances. I will try to pick up from that point and not repeat any of those remarks. Certainly all the cases presented this morning by our three colleagues demonstrated good response to treatment. They are satisfactory cases, but still there is a void here. We must not be led to believe that all cases respond in the way that these have. Again, as we examine the cases on display, such as the American Board cases, we realize that the results represent the outcome of treatment of those particular cases. It does not necessasily follow that treatment of an apparently simi1a.r case will produce the same result. We must admit that there are also cases at home that have not responded to this or that therapy. I am fortunate, possibly more fortunate than you people, that I do not have to wait for these eases to be transferred to my office ; I have them at home waiting for me. They are there every day, and I think that as we delve into appliance therapy we tend to overlook some of the basic points as to why a case responds and why it does not respond. First, patients are different, no matter how identical the casts, may seem to be. They differ in facial patterns, in increments of growth during and subsequent to treatment, and in the timing of growth. There are many ot,her differences involved, so it is very da,ngerous to compare one case with another, whether they were treated with the same appliance or with different appliances. We can only speculate, see the result that, is produced, and wonder: “Now: if something else had been done-if this had been treated a different way at a different age-what would the result be 9” i We ean come up with a presumption which might fit our basic reasoning, our backgrounds, our experiences, but that is all that it can be. We presume that it would have been better if somet,hinp else had been done; we really do not know, and we must realize that. To understand our cases, we must evaluate them in a reverse direction.

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We must take the finished results and then look back to see what has occurred, and we learn in that direction. We do not know enough yet to look into the future to determine what is going to happen next year or the year after, and that is very important. I have some different opinions, naturally. You heard Dr. Wilson’s earlier remark:s, so all I can ask is that my colleagues be very reasonable and that they just agree with me! In the matter of treatment, I have seen children in my practice grow up wearing one appliance or another. It is well to speak of early treatment to take advantage of growth. Frankly, I am thinking less in that direction than I di.d some years ago. The growth that I really like is the puberal growth spurt, at the age of 13, 14, or 15, whichever it might be. If I am lucky enough to be treating the case in that period I get a good result, presuming that I do the correct thing mechanically. If I treat in advance of that puberal growth spurt, the response to my appliance therapy may be slow, and I might. get excited and try something else. If I treat after this growth spurt, that is unfortunate; I may not be able to achieve the same result. There is a lot of luck in this at the present time, but the more we study our treated cases the better guessers we will be. I blelieve that both Dr. Bowyer and Dr. Moore stated that two of their cases would have been extraction cases if they had not been treated early. I cannot quite accept that; I am not sure that they would have been extraction cases. It might be that a very successful result would have been achieved in those cases if they had b’een treated when the patients were 13 or 14 years of age. W:hile I see the splendid results in their cases, I am thinking of other cases in which patients who ha,ve had similar therapy now say : “Well, Doctor, this is the sixth year.” That gets to be embarrassing, because not all patients responld so readily to treatment. I .would like to conclude with a statement with which my colleagues will disagree. I would like to say something about function. In treating these younger patients, I hesitate to establish a tight incisor contact at too early an age. By “tight” I mean an absence of overjet, with maxillary incisors back against the mandibular incisors, in an B-year-old, a g-year-old, or a 10..year-old child. Who am I to decide where that maxillary incisor should be in space? There is so much growth ahead, and it is quite possible that if there is more mandibular growth than maxillary growth after I have established the tight incisal relation, I will very often introduce severe functional problems: interferences, and clicking or crepitus of the temporomandibular joints. These problems can develop when the mandible cannot move in a downward and forward direction as a result of its growth. With respect to growth in treatment, I do not believe that we are stimulating growth. beyond the alveolar process. I do not believe that we are inhibiting growth.. I do not think that any of you stop a Class III relationship if it is really going to be a Class III, although you may change the alveolar process. I do n’ot believe that we are changing basic facial. patterns appreciably by our treatment. We do modify and influence the alveolar process. If this influence is exerted at a time of active facial growth, we bring about a

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considerable change in tooth relation, Very oftcn we make the mistake of interpreting that solely as tooth movement. However, it may be slight tooth movement in a face t,hat is growing very actively, and when we later superimpose cephalometric tracings we interpret it as being tooth movement. In conclusionF I feel that our treatment. is limited to the alveolar process. I feel in no way discouraged by this. We can still make considerable changes in the dentitions and faces of these children. Dr. Wilson: Thank you, Dr. Thompson. Dr. Shepard, may I direct a question to you ? I note that as part of your treatment you are inclined to drive upper molars distally. This is done in certain deficiency cases, and there would be a What are you doing logical claim that in so doing you are avoiding extraction. to the second or third molars? Are you, in effect, not condemning some of these teeth to extraction? Is this not an extraction process in itself? Are we deluding ourselves when we drive teeth distally? Dr. 8hepard: It is certainly quite possible that we are trading extraction sites, so to speak. I feel that I would much rather do that. I am not saying that I, personally, do not extract premolars: because I do. I feel that if we can extract in the posterior area rather than in the premolar area; we are perhaps providing for a better regeneration proeess together with space tightening. Dr. TYiZsoti: Do you have any comments on that, Dr. Reid? Dr. Reid: May I ask Dr. Shepard if he resorts to second molar extraction where he wants to avoid the very same thing Dr. Wilson mentioned? Dr. Xhepard: Depending on the radiographic appearance of the t.hird molar, of Course, I sometimes do. I might say that on occasion this so-called backing-up of molars or driving of molars (or whatever you want to call it) may result: particularly in older paCents, in a buccal movement of the second molars. It then behooves us in one way or another t,o place a baccal spring against the second molars to correct, this situation, but I see nothing wrong in having to do things of that nature. D,r. Reid: If I may speak out of turn again: I would like to ask Dr. Meore zrbout the cases in which he uses extraoral traction on the maxillary arch. When Dr. Bowyer uses the guide plane and his patient is functioning ahead of the guide plane itself (or it could be a fixed bite plane, such as Dr. Jackson in the audience would use, but in either case the patient is functioning in a forward position), would you feel that the drag back on this lingual appliance might serve pretty much as the same retardant to oral development as extraoral traction does? I do not know whether Dr. Bowyer would agree with that. Dr. Bowyer: I think we do so, Dr. Reid. However, I do not think that is the entire action. I happen to be one who does feel that we can stimulate forward growth of the mandible at an early age in keeping wit,11 the biologic principles that Dr. Baume so capably presented to us here at this meeting, I think that, T get some distal movement of molars, yes, and I think that, it is desirable in manJ @lass II cases; however, by control of anchorage, I can also u.se a, guide plane and keep from driving molars distal. I can drive them with a. guide plane, or I can limit this movement.

DY. Reid: Dr. Moore, 1 was really you feel about that?

directing

the question to you. How do

Dr. Moore: As far as driving the molars distally with the guide plane is concerned, I do not know whether it can or cannot be done. The possibility exists that a distal force is created by the mandible and its musculature through the action of the guide plane against the maxillary denture. One of the results that I would like to see come out of this discussion would be that everyone-regardless of the technique that he may use-would evaluate his ca,sescephalometrically to find out wha,t he is doing. As a matter of discussion, we can say that we are driving teeth distally, that we do this or we do that, but these are merely opinions. As Dr. Wilson said when we started out, we can rationalize these things until six weeks from now and we still would never come to a definite conclusion, because u;e do not know. It is time that, regardless of the appliances that we are using, we objectively analyze our cases. I feel that it is possible, through the use of the bite plane, to hold back maxillary growth during treatment the same as we do with the headgear or with any other posterior force. Dr. Xhepard: At Washington University in St. Louis we did some cephalometric studies on .the guide plane. Treatment actually showed a, posterior positioning of the maxillary first permanent molar. Then subsequent tracings showed that this tooth did take its place more forward after several months, which is either a mysterious happening or the effect of the patient’s growth. This was the experience in a rather large series o,f cases when studies were done cephalometritally on the guide plane. Dr. MooreI: Certainly, we see many things in head films that we cannot understand or explain. There are loopholes in the interpretation of head films, but I think that this is about the most objective way in which we can deal with this particular problem. A little while ago we mentioned the axia,l inclination of teeth. I do not t,hink t.hat we can assess this from looking at photographs, dental casts, or anything else. The only objective aid that we have is cephalometric evidence. Whether we carry teeth bodily distally, whether we tip them back, or whether we carry the roots forward and the crowns back can be evaluated only with headfilms. I think that we can talk intelligently about this only if we are usming cephalometric headfilms. Dr. Bowyer: The most avid advocates of eephalometrics will also admit its shortcomings and limitations, just as we are doing. As Dr. Baume so nicely pointed. out to us, we are assessing a three-dimensional problem in a two-dimensional analysis. Therefore, we must admit that it does have its limitations. I a:m inclined to rely more on biologic research, such as that which has been presented at this meeting, to show that you can position the mandible forward and that you can stimulate intrachondral ossification on the posterior surface of the condyle. I am willing to accept the findings of outstanding biologic research men.

Dr. Moore: Dr. Bowyer, I do not have many monkeys in nq practice. (RFs’erring to Dr. Baume’s experiments on monkeys.) Dr. Thompson: I would like to add a point here. .We can all appreciate acid we very often listen to pure bas#ic science, but I am sure that if we would atten.d r,he meetings of such scientists we would find them going around in circles with considerable disagreement over their particular problems, just, as we are doing here on this panel. There is a danger of leaning so heavily in that direction that we get lost in the woods of deep, complex things. I think that we rationalize then, and that is what you have done, Dr. Bowyer. You have seen a smattering of evidence, of which I would have to see a, lot more to accept at all, but it is evj.denee that you like to see. I was not necessarily looking for it, but I was not at all convinced by the experiment on the monkey that it is something which we can expect a,nd necessarily follow with respect to human patients; nor was 1 convinced that the tracing shown by Dr. Baume showed a change in the form of the mandibular condyle by any means. Because of my interest in the t,emporomandibular joint, I have delved into tracings, head films, and mandibular condyles for a good many years. I place very little confidence in lateral points in cephalometric radiography for deter!nining what happens to a molar, or to a condyle, before and after treatment. I think that we are being unfair to the technique if we rationalize or interpret too far in that direction. Cephalometric radiography is a very accurate means of evaluating midline points, very definitely. I agree wholeheartedly with Dr. Noore that we must have these reeords and we must know t’hat we are just looking at the patient. However, we are getting away from what Dr. Wylie called the “numbers game” of just setting people up and comparing them to standards. ?Ye realize that this is not entirely valid; it gives us only clues-generalizations from which to work-but we should look at the head films and learn something from them. Dr. Bowyer: I certainly agree with Dr. Moore. Neither do I have any monkeys in my practice. I doubt if many physicians have rats in their practices, and yet I think that they do a considerable amour,t of cancer research on rats. I think Dr. Asling showed his research on rats in producing cleft palate. I do not think that any of us have rats in our practices, and I submit, tha,t a monkey pomes a little closer than a rat to being a human being! Dr. Thompson: I promised Dr. Moore that I would never tell you something that happened when he was a graduate student. He happened to examine a child of one of the interns, and Dr. Moore pointed out a condition that is rare in human beings and very common in monkeys. He has an aversion to monkeys uow because of the parent reaction. Dr. Moore: Dr. Bowyer; I would like to direct a question to you, for you were talking about arch length discrepancies-at, least, this was pa,rt of the sub.. jeet matter that we were discussing. We always look at the extraoral x-ray films to see if the roots are parallel in extraction cases. I have seen some of your extraction cases, and I know that you do it. Would you give me a brief explanatiou of how, with a labiolingual appliance, you pa,rallel roots in extraction eases?

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Dr,. Bowyer: Yes. This varies also with individual cases. E‘irst, may I point out that with labiolingual procedures we are not completely averse to the use of auxiliary bands and attachment bands, and frequently we will retract cuspids by banding them and using various types of auxiliary springs. In many cases in which four premolars have been extracted, if there is a slight mesial inclination of a lower cuspid, as there frequently is in extraction cases, I use an upper bite plate with a vertical recurve spring to move the upper cuspids back while I am getting vertical dimension with the bite plate and I do nothing to the lower cuspids for six or eight months. It is amazing, if we just leave things alone, how those lower cuspids will go back a great deal by themselves; sometimes over half of the space is corrected in a lower arch without anything being done. Then it is very easy to place a lower lingual arch with an 0.018 inch loop spring off of the lingual. This exerts a very, very gentle stimulating pressure, and it moves the cuspid distally. We find that with a very gentle pressure we can move cuspids distally without distal tipping. If .we use a strong pressure, certainly we would get distal tipping. However, I think it is a matter of using very light stimulating forces. Placing the pressure point as deep as we can in the interproximal with very gentle pressure is the significant factor. In evaluating x-ray films in extraction cases treated by labiolingual procedures and looking at posttreatment films of the area, my experience has been that in most cases where extraction is really indicated teeth can be retracted just as nicely and just as vertically, with roots just as parallel, as with a multibanded appliance. Dr,. Wilson: As a labiolingual man, may I take issue with some of the remarks that Dr. Bowyer has made. He has rightly pointed out the very pertinent fact that the amount of tipping is related to the relationship of the point of pressure application to the inherent resistance. If this point of pressure application is low, deep gingivally, and gentle, as he has suggested, he will get a maximum of movement with a minimum of tipping. However, I find myself, as a labiolingual operator, guilty of the things that Dr. Moore has just indirectly suggested. I find that I am not able to parallel roots with the degree of efficiency that I know he and Dr. Thompson or some other men who use edgewise appliances can do. I feel that this is a deficiency of my appliance. Admittedly, there are many cases in which there might be a 7 mm. deficiency in an arch, and if I remove a 7 mm. premolar there is no problem. Where I remove a 7 mm. premolar i.n the presence of a 3 mm. deficiency, I will be faced with a 4 mm. spaceclosure problem. As the increment of space closure increases, then my degree of efficiency in paralleling roots decreases. This is an area in which perhaps because of my own deficiencies, I am unable to parallel roots as adequately as an edkewise man or a man using similar appliances with similar rigidity and tooth control. However, I must add something else. With the technique as many labiolingual operators use it (and as I believe that some twin-arch men also use their appliance), we are not faced lvith the necessity of removing teeth as often as an edgewise man is, so we are less often faced with a 7 mm. or 6 mm. space-closure

problem. There is perhaps a little different thinking in our concepts a,bout the possibilities of distal driving, of uprighting teeth, and of slight arch expansion which will give us an increment of 2, 3, or sometimes 4 mm. to work with. Rightly or wrongly, t,his is what we are doing, and in so doing we are removing ourselves from the periphery in which we find this problem of great. space closure existing. This does not alter the fact that all cases do not fall into these nice clear categories where we have an “either-or” proposition. We can run into problems in which there might be a bimasillary protrusion, with arches well rounded out. We feel the need to reduce the anterior teeth, and we have a full 7 mm. space-closure problem with parallel roots. Here I find myself, as a labiolingual operator, less efficient than a capable edgewise operator under t,he same circumstances. I might also add that I have found noticeable instances in which men using the edgewise appliance rightly or wrongly have failed to achieve the high deqee of parallelism that good operators achieve, I)r. ,Woore: Certainly those of us who use the edgewise appliance recognize some of the limitations that are imposed by the thickness of band material between all the various teeth. I think t,hat we have all had experiences in which, when we finally got the malocclusion ful.ly banded, we had a. much more severe discrepancy problem than when we started the case. In recent years we have become more cognizant of this, especially in those ca.ses in which there is a eertain amount of crowding to start with. In the second case that I presented here, there was crowding of t.he lower incisors; it was not marked, but nevertheless there was enough that,, coupled with the band thickness, there was a considerable amount of crowding. That case was treated with a mandibular headgear. We have to compensate for some of the deficiency of the appliance by applying other forces. Throughout treatment the patient wore a mandibular headgear in conjunction with the Class II elastics; the mandibular hea,dgear permits us t,o gain arch length posteriorly in order t,o align the anterior t,ecth, but it complicates the treatment. Dr. Bowyer: May I ask Dr. Thompson to clarify a point % You stat,ed? I believe, that you felt that our orthodontic treatment was limited to alveolar bone areas, and then you also stated that you preferred to get your cases during the puberal growth period. Why do you prefer them during that period! Dr. Thompson: Because that is a period when the face is enlarging a considerable amount in a very short time. I think that any appliance therapywhether it is what you have advocated or what Dr. Moore or Dr. Xhepard have advocated-will respond better at a t,ime when the face is enlarging. I think that we have all had experiences in which we have treated a youngster for maybe three years and accomplished more in the t,hird year than we did in the previous two years put together. That is not a reflection of our therapy; it is a matter of applying forces at the time t,he face was actively enlarging. I like to treat functional problems early, but those involve relatively short, periods of treatment. I like to treat structural problems later, because I am afraid that I would place teeth in positions Tvhich will conflict with future ja~\r relations after the child has gone through t,his pubera growth -period.

Panel discussion Dr. Reid: I would like to ask you, Dr. Thompson,

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281

you can

predict the puberal growth spurt, and whether you might run the risk of having referring dentists send you patients later than you would expect. In other words, would you make more errors in not getting there fast enough than ;you would by starting too early! Dr. Thompson: I do not by any means tell. the dentist that I do not wish to see the patient until he is a teen-ager. That is absolutely wrong. I wish to see the children as early as possible, and try to treat them when I can do the most in the shortest period of time. (I sa,y try; I do not really know how I can tell because I cannot predict.) I know that it would help us tremendously if we were able to predict. I predict in the reverse direction. In that way I can tell what has happened., but it is difficult to tell what is going to happen next year in a child. I have no objection to treating gently, trying to see what the response might be, but I have seen entirely too many children grow up with long periods of treatment in my office, and I do not think that I have helped them a great deal in all those years. I think that again we see some rather bizarre things happening after this later growth. When I have forced maxillary molars distally, changing from a Class II to’ a Class I relationship, I find that sometimes after premolars have erupted there are some spaces that are rather difficult to close because the maxillary mola,rs are actually posterior in the facial pattern. Again, when I have retracted incisors too far lingually too early, I find that incisal interference may contribute to irregularity in the mandibular incisors plus t,he functional disturbances involved when such a condition exists. I assure you that I have no answers that are going to help anyone in determining when to treat cases, but I have not been satisfied with what has happened up to now. Dr. Wilson: Dr. Thompson, most of our time is spent in removing the undesirable interlocking of teeth. When you see this beginning at an earlier age, are you going to sit idly by and wait for it to occnr% Dr. Thompson: If I believe in my own mind that it is functional, if I see a child with clicking and crepitus of the joint at an early age, if I recognize a case as being one of mandibular displacement, I will try to eliminate the factor that I feel is responsible by equilibration of the deciduous dentition and movement of certain permanent teeth. I guess that goes back to what Dr. Rogers tried to do many, many years ago in re-forming a maxillary arch and then waiting to see what happened. That does not take too long-just a short period of treatment. Dr. Shepard: Dr. Wilson, are we not in effect doing practically the same thing in practicing interception? I think that, regardless of our appliance therapy, we are all recognizin.g those cases in which trauma would present dire results to the mouth, so we are treating early in a so-called first phase type of treatment. Incidental to that particular type of treatment, we are gaining such results that many times we go right ahead and finish the case when we had originally planned that we were just going to get in and get out. At an early age some of these things jump right into place so rapidly and so well that I think that, without respect to appliance, we are following the sa.me type of rationale.

0~. Thompson: What about the ease that, does :IO~ JXSPOI~ il<)w:2 Dr. Bhepard: We are faced with the proposition Lhat we must take care JL

“,eeSh that are extending down over the lower lip and things of that nature. %any times society forces us to do that. VCTeare not forced, but we are required to do it from the standpoint of our rapport with dentistry. Dr. Moore: Dr. Thompson, it has been my experience, as well as the expti:rience of some of my colleagues who have been using headgear for approxi:nately ten years in early or mixed-dentition Class II problems, that the number .>f cases that require a second period of treatment has been a great deal smaller !lhan we anticipated when we first started to use this form of therapy. I would jay that in about 70 per cent of the cases that we treat with headgear and lingua? arch (where necessary), bite plate, and probably maxillary incisor bands to control she final positioning of the maxillary incisors, no futher treatment is necessary. I would like to be right 70 per cent od the time; I feel that this is a good average. Dr. BozL;yerr This has been my experience with labiolingual treatment in cases of the type that I showed. I have no accurate record of percentages; let 1~ssay that it is just fifty-fifty-50 per cent will respond and 50 per cent &-ill not. My personal thinking is that we should not deny the 50 per cent of rhe children who will respond constructive help because we fear that they might be among the 50 per cent who will not respond. In my consultation with the parent, I freely admit that I cannot predict exactly what is going to happen. i alert the parent to the fact that, in my opinion we can help the child ait that time. I suggest that we start with some corrective procedure for a few :nonths, and by “a few months” I mean that within six months I can tell whether or not I am going to get response. If, at the end of six months, progress l&s not been favorable I call the parent in and I admit the problem. It is not :~:y fault and it is not the parent ‘s fault; the child just did not respond. We !lave anticipated this ahead of time. We discontinue treatment, and then we v;ait until the puberal growth period. Extraction is often necessary in these .zses. I strongly believe that the percentage of success is great enough that WC certainly must intercept and treat, and we do treat children in the mixed-dentision stage. Dr. Reid: I agree wholeheartedly with Dr. Bowyer on that, and I agree ivith Dr. Moore on his headgear treatment, but I have a question about the latter. I have enough trouble getting my patients to cooperate by wearing interrrlaxillary elastics. How long would you continue a primary stage of treatmeniwith a headgear in a patient who was not cooperative? I ask you that because m some of the case reports I notice that a headgear has been used for a year ;~rld a half without, much success. How do you handle tha,t particular problem? Ur. Noore: The problem here is to be convinced, yourself, that it will work. L~‘L us go back in the history of appliance development,. The belief was that if vou wanted to use a multibanded technique the children just would not stand ?OYit. They would not wear multiple bands; multibanded techniques came out; ;IJWRV~L.,and people did stand for them, and this is a very popular form of treat:ibertt today. The same thing is t,rue with regard to hea,dgesl*. When you a,re

Panel discussion

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convinced of the results that you can achieve with it, you can do it,. It, is a matter of convincing yourself that this will do the job. AS for children not cooperating, we all have a few of these uncooperative patients. Usually both the parents and the child are to blame. We just discontinue treatment because there is no way that we can succeed unless the child wears the headgear. I usually present it in this way when I talk to the parent: “If the child is not going to wear the headgear and wear it faithfully every night, let us not waste your money and my time.” In speaking to them very frankly that way, I have minimal problems as far as cooperation is concerned. Dr. Shepard: Dr. Moore, may I ask this question: How about school-time wearing of cervical traction and the like ? Will you make a statement on that? I think that is very important. Dr. Moore: I do not request or require my patients to wear such appliances to school. I ask that they wear them twelve to fourteen hours a day. I had one patient, however, who was kind of a show-off, and he wore his headgear twentyfour hours a day ; he was an extrovert, and the headgear was a badge of didtin&on as far as he was concerned. I have never requested such continuous wearing, and I have found that I can achieve the same results without it. D,r. Wilson: Dr. Moore, I know it works, but are you concerned about the fact tlhat your headcap is worn only over a certain period of the day! Why is it that some orthodontists seem to shy away from mandibular anchorage? D,r. Moore: I think that when we are treating early we are doing things to the facial pattern of the child that actually have a more far-reaching effect than Dr. Thompson implies when he says that we are dealing only with the alveolar process change. I am firmly convinced that we are actually altering the facial growth pattern of the child. Thus, in my practice headgear is used in Class II cases because I want treatment to have this effect on the developmental pattern of the child and I feel that this is the best way of achieving it. The mandible will take care of itself in many instances. Dr. Wilson: Let us take a hypothetical situation. Suppose that adequate mandibular anchorage were set up, and that we then were to embark upon a proces,s of distal driving of maxillary molars which would, in effect, be the same thing that you are doing. Would we not achieve the same result and provide an added stimulus to growth? We are getting involved in semantics here, but a certain segment of our specialty feels that this is a valid procedure. Certainly, distal driving of maxillary molars is a valid procedure. We use it for several reasons: First, i.n driving maxillary molars distally, we open the bite anteriorly. In so doing we also relieve the pressure of the premolar interlocking. The two great sources of resistance to normal full mandibular growth would be interlocking in the buccal segment or an excessive anterior close-bite. The goal of relieving these, in itself, justifies the process of distal driving. In. addition, we feel that the added increment of pressure application for Class II mechanics does yield a favorable result in many, though not all, cases. We see cases in which mandibles will reposition themselves on occasion with no intermaxillary anchorage but with the mere slight widening of an upper arch

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iorward mandibular growth. Maybe this is an illusion; maybe we are kidding ourselves. I am speaking now of expansion. Is this an ugly word? Can we expand “t Dr. Moore: I certainly agree that we can expand in certain cases in which the teeth have been contracted prior to the time that we start treatment. I think that we have more or less documented or found the same results that Dr. Strang found in his studies on the intereaninc width where he feels that we cannot successfully expand. Cases out of retention always seem to return to the dame intercanine width, so I do not particularly like expansion in the canine region. As for your discussion concerning the use of Class II elastics and distal driving of buccal molars, I think that the effect is exactly the same as that, which we get with a headgear. The only thing is that this part of the result that you achieve is due to growth. I have never been convinced, myself, that this little nudging is going to stimulate mandibular growth. You might say &at if the child is not growing at the time that you are applying this elastic force, you are probably strainin -g mandibular anchorage and tending to move the mandibular denture forward on the skeletal base. If the child is growing at that time I would say “fine,” but if he is not growing we might be doing something to the mandibular denture that we would not desire to do. Dr. Thompsofz: Dr. Moore and I are not so far apart on this as it sounds. Re just made a statement which shows that he fully appreciates the significance of facial growth. My only argument is that we are interpreting too far our influence on growth of the face and on changing basic facial patterns. We can accomplish a great deal by modifying eruption of teeth, restraining alveolar growth, or changing the direction of eruption of t,hese teeth. However. when you carry it further to talk about inhibiting maxillary growth or doing something to the condyles, then I have to say that I have never seen evidence w support those statements, I certainly agree with Dr. Wilson’s remarks regarding the case where, in reshaping the maxillary arch, one sees the mandible come forward. That, to me, is a functional plan, and I try to do exactly that. It takes a very short period of not more than a couple of months of treatment. If the mandible does not, respond? then it does not respond. I also treat many 8- and g-year-old children for a few months to eliminate ?ncisa,l interference. Here some of you do not seem to fear creating incisal irtterference in children 9, 3.0, or 11 years of age, but I fear it a great. deal as a factor that will disturb the incisors functionally and will disturb the position of the mandible as it grows. Regardless of what appliance you are using, whether SOLI are positioning t,he mandible forward, whether you are moving maxillary molars distally, whether you are using labiolingual appliances, or whether you are using headgear, you get a favorable response if that face is enlarging. If it is not enlarging, the response is not so favorable.

Volume Number

48 4

Panel discussion

285

Dr. Wilson: There may be a response. You may open up spaces, and things may drag on. We blame it very often on poor cooperation

of the child, but growth is pretty-important to all of us. If we are ever going to agree on anything, it can be the significance of the growth of the face as it influences all thera.py.

Dr. J4oore: Dr. Wilson, I think one of the interesting things is that as we talk about the wide divergence of opinion as far as appliance techniques are concerned, yet we are all using the same forces in the same direction. The met,hod of application is different in. terms of which teeth are banded, but the same forces are used and we are all getting essentially the same results. Thus, I think that part of this problem of differences in appliances is semantic. As you pointed out, there are many edgewise men who do a very nice job of paralleling roots in extra.ction cases. There are also some who do a very poor job of this. It is not the appliance but the man behind the appliance. If he has a. correct concept of orthodontic therapy, he is going to achieve a result that we cam all appreciate. Dr. Xh.epard: May I explore another facet of treatment which has to do with so-called arch leveling or intrusion of anterior teeth and extrusion of molars. I think, Dr. Moore, in your case you showed an appreciable extrusion of the mandibular molars and intrusion of the incisors. Did you not? Dr.

Moore:

Yes.

Dr. Xheprd: I would like to go on record as being certainly very much interested in this particular facet of treatment and as recognizing its great importance in opening bites. I a,m sure that it occurs, but I would like to ask Dr. Bowyer to discuss the extrusion of molars. I know that by opening the bite or destroying the contact between the upper and lower teeth you are bound to get it, but how does it work with ;your anterior teeth with respect to intrusion?

Dr. Bowyer:

Do we intrude

lower teeth with a guide plane?

Dr. Sheparcl: That’s right. Dr. Bowyer: No, we do not. My personal feeling is that severely intruded lower teeth have a tendency to re-elongate when pressures are released. I do not mean to say that you should not intrude teeth to some extent. Personally, I prefer elongation in posterior areas. This is one advantage which we feel the occlusal guide plane has over (occipital anchorage and posterior movement. With a properly constructed occlusal guide plane, we not only position the mandible forward but we c.an also change vertical dimension at the same time. T!he posterior molars are slightly out of contact when the occlusal guide plane is placed, but they very rapidly come back into contact. If the molars are moved distally, as Dr. Shepard pointed out, we get even more increased vertical height. This is important, because the relapse that we speak of so frequently in lower anterior teeth is often due to a lack of vertical dimension. Personally, I prefer

SOget as much vertical dimension as I can as early as 1 possibly can; thereb> I also eliminate some of the anterior trauma that Dr. Thompson mentioned. We certainly do not retract the anterior teeth to the extent that they are tipped lingually in the mixed dentition. My personal feeling is that we would bring the anterior teeth lingual only to a, relatively vertical posit,ion-certainly rmt beyond that point-and that we should not hold them back in close relation to the lower teeth. Very frequent& in the first stage of treatment I leave some overjet. I do not attempt to get an end-result anterior bite relationship in -the mixed dentition, but I do certainly like to treat the teeth as I did in the ease that &owed. We get the teeth back from outside the lower lip, relieve the interference of the musculature, and bring the maxillary incisors back to a, relatively vertical position somewhere in the area where I wish them to be in the completed case. Then, by using a lower appliance, we can also correct an)- rotation and crowding in the lower anterior segment, as Dr. Moore did by t.he use of a simple lingual arch. We feel that, we want and get vertical opening with the use of a guide plane in the mixed dent.ition: L)r. Xhepcwd: Dr. Bowyer, do you ever resort menting this particular thing ?

to anterior

bands in aug-

.&. Bowye?,: Certainly, very frequently we will use a twin-wire appliance. l’he nice thing about the labio’lingual procedure is the adaptability of combining the two. I think that there are very few men using labiolingual procedures who do not also use bands when needed for rotations. As I mentioned, we use bands frequently in the retraction of cuspids. However, we band only t,he teeth that we feel we need to band to control the positions of t,hose particular individual teeth. We do not consider it necessary to band all the teeth merely to collt,roi the positioning of one or two individual teeth, such as lower cuspids. L)v. Reid: I would like to bring out one more advantage of the guide plane, w~lich Dr. Bowyer does not use exactly as I do. He uses the official guide plane! and I use u-hat could be termed a fiscd bite plane. Both appliances give the vertical opening which allows the lower ca.nines to be expanded. It does not take a lot of lower canine expansion to make up a couple of millimeters of arch length deficiency. You immediately pet this opening, which you do not get when you are treating without a bite plane, As soon as the space problem is solved in :he mandibular arch: the teeth settle down very quickly. As Dr. Bowyer brought ,Jut, when posterior teeth are kept apart they do settle into occlusion quickly; then we remove the fixed bite plane and we have a lower arch band with adcquat,e arch length to use as anchorage in distal driving. There is one other use of the guide plane. I sometimes band both the second molars and the first molars and t,he upper arch and use a coil spring on the labial arch between the first, molar and the second molar, driving the second molar distally independent of the rest of the arch along with a fixed bite plane which is act,ually doing the same as extraoral. anchorage. In a small degree, a:

Panel discussion least, it is holding

back any

forward

movement

of the maxillary

28 7

arch. I feel

that >wegetpretty goodcontrolof the distaldriving. Dr. Bowyer: Several times multiple bands have been mentioned. I wish to make it clear that I, personally, have no quarrel with anyone who uses multiplebanded procedures, banding as many teeth as he considers necessary. It is very pleasing to me, h.owever, to find that, orthodontists who use the multiple-banding techniques are very rapidly reverting back to the light wires. This is the phi1osop:hy of the labiolingual procedure-light, continuous, stimulating, gentle forces-and I think the quarrel that we in the labiolingual camp might have had (if we had any) with the edgewise technique concerned severe pressure and forceful tooth movement. It is most encouraging to me to find that more and more the men who use multiple bands are now using the smallest and gentllest arch wires they can for tooth movement. We are all coming to a meeting of the minds on this. Dr. Thompson: Let us say that some of the men are doing that. Lbr. Bowyer: All right, some of the men are doing that. L;br. Reid: This is just a short question directed to Dr. Shepard. I know that you use primarily a twin-arch technique. How do you handle a Class II, Division 2 case ? This gives me a lot of problems with. retruded anterior teeth where I would like to change the axial inclination of the root or to attempt to move point A lingually with the twin-wire arch. I cannot do it, and I know that in some of my cases the patients have a strange appearance when t,reatment is finished, even though the occlusion otherwise might be good. D’r. Shmepard: I think that probably the one great fault with this appliance is that you do have, in effect, a result that looks like the old-time (and I stress the “old time”) extraction result when you have ended with a Class II, Division 2 malocclusion. My principle of treatment is to utilize no maxillary lingual appliance, to allow time for the maxillary anterior teeth to be aligned, and to go immediately to distal driving of the molar right after this has been done. I certainly agree that, esthetically and functionally, these are not as well treated as I would like to see them. Dr. Moore: The edgewise group have been criticized for their narrow viewpoint and multibanded technique. You have seen that today we used the labial arch, the lingual arch, and bite planes-all of these things. I think that you were possibly impressed that we cont,rolled the axial inclinat,ion of the maxillary incisors. Now, could I get you to use some edgewise brackets on the ant,erior teeth and torque these tooth root,s b’ack? Dr. Wilson: I think that Dr. Moore has put his finger on a very pertinent point. There are certain areas in which each appliance has certain advantages over each of the other appliances. Likewise, there are certain areas in which each appliance demonstrates certain inherent deficiencies. It is this area that demands wisdom and judgment and, to a degree, the ability of the orthodontists to adjust themselves to these changing situations. I am sorry that I must at this point terminate this discussion, but our time is running out and we are getting m-ore involved, which is the way I expected it would be.

St38

aime~icun.

,Issociatior~

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Orthodont~is?.~

;1,lL, J. 9rthodormca Afwil1962

Dr. Bowyer: Dr. Wilson, could I make one very brief statemenel b)r. Wilson: This is what I mean. Dr. BOWYW: I certainly agree with my friend and colleague, Dr. Moore, anti R think that he and others who have open minds and are using other things are certainly to be commended. I assure him that those of us who have not been using some mu1t,iple bands should do so. I would like to make one specific reference, Dr. Moore, in addition to lingnal torquing of roots. This concerns the deep curve of Spee in the lower arch. With the occlasal guide plane, as we position r’orm-ard many times me will get normal elongation to a leveling of this arch, but in the permanent dcntition many times WP will not pet it, and I would 2ke to tell you that I have used multiple bands in leveling oixt lower arches. Dr. Wilson: It becomes very obvious that we have heard varied and objective reasoning as well as subjective preferences. Tt is quite clear that orthodontics, being as complex as it is, is not som.ething that one can wrap up in one tight :ittle package. Orthodontics is both an art and a science, and certainly not an exact science. In certain areas, at least, there are no precise answers that we can sope to arrive at; instead, we are faced continually with the problem of differences in objectives and certain subjective preferences of which WC toda: have just scratched t,he surface. It seems that these differences still would tend to carry us in divergent directions, and this cannot continue. It would seem that this has been a resnlt of restrictive dogmas which have arisen because of certain experiences tllat men :lave had in eerta,in areas. These have motivated them to set down certain lines of treatment. Perhaps others have embarked upon some types of treatment in$diciously and have had failures. This has led them to set up certain restrictive dogmas, such as ‘“Thou shalt not expand or ext,ra.ct, or distal drive.” Ve have heard them all. Thrsc have been restrictive and arc a great deterrent to progress in orthodontics. I think that, Dr. Moore put his finpcr on the vital point, namely; t,hat sysrems themselves are essentially good-they arc necessary. A systcrnatic approach xo an appliance certainly is necessary for the proper use of the appliance. As he suggests, however, when a s>-stem begins to cause a universally exclusive: ordered approach to a problem, it tends to make the orthodontist a servant under the control of a so-stem and produces some irxolnt-ed, nonthinking techniques. This. T submit, is bad. Perhaps it should not be surprising that, this is the case, for Albert Einsteirr said : “There are two characteristics of the age; one is perfection of means, and the other is confusion of aims. ” Certainly. this confusion is a luxury in which M-e are not free to indulgc9 because time is wnnning out. T t,hink that all. of us sense certain sociologic changes in our time. There are those of us who feel that, &se threaten our dedicated Selief that we can best render human service under our own autonomous control. When we are faced with this ugly specter of outside control, we cannot meet it Sy any stubborn c.laim to “our rights.” Ra,thcr, we will have to meet it by sorn(‘ demonstrated evidence of our ability t,o meet the demands placed upon us. We have not too much time, and we simply must get around to putting 0111’

Panel

discussion

289

house in order. We must resolve some of these objective differences, and we might even have to abandon some of the subjective preferences which seem to dilute our functioning. We must make attempts to broaden our base of agreement and then further direct our efforts to a more adequate public service. If this is to occur, even after today’s session, I feel more firmly convinced that we shall have to diverge more frequently from the authoritarian program of lectures and indulge more frequently in honest, open conversations in which we discuss our problems and our failures. This is the process that breaks down the rigid dogmas, and we will have to analyze not only the old concepts but also the new ones that come along. We will have to analyze these, to probe: to embellish, to discard, and perhaps even to search again. We are going to need mo’re workshops directed not to peripheral problems but to the heart-and-core problems of orthodontics, and we are going to need more open-ended discussions of this sort. All of these are going to fail, however, unless we ourselves have the proper attitude in the face of this requirement which is thrust upon us. Certainly, we must be free to reject dogmas in favor of testing concepts by their fidelity to observed facts. We must be willing to throw off the slough of blind adherence to systems and to embrace a universality of understanding, such as we began to arrive at here today, and we must do this without emotion. We can very well take heed of Aristotle, who said : “When emotions enter, reason leaves,. ’ ’ We do not want conformity just for the sake of unity. Nonconformity is a remarkable weapon against mediocrity. Conformity, in itself, is neither good nor bad; it is what we conform to that really creates the problems for us. The nature of orthodontics being as complex as it is, and having just touched upon a few things today, I think we have demonstrated the need to touch upon many more. We are going to have to live in the presence of many uncertainties and in the face of problems which are not going to be solved in our time. This places some demands upon us to adopt an adequate philosophy. I would like, in closing, to submit to you a philosophy which I know appeals to Dr. Moore also. That is the philosophy of Dr. Rheinhold Niebuhr, our contemporary American philosopher, who says : In these times man needs three essential qualities: courage, tranquility, and wisdom. We need courage to change those things which can be changed, and tranquility in the face of those things that cannot be changed, and the wisdom to distinguish

between the two.

As your moderator, I have one other function-to act as your representative. Like the two-headed Roman god, Janus, I am going to assume another head, and for one moment more I am going to a,ddress myself to the men here in this open session. I want to express on your behalf appreciation to these men who have been willing to come here and participate today. Many of us have realized that t:his is something which needed to be done, and you men today, by your contri‘butions, have demonstrated that it can be done. This, in itself, is a notable contribution to orthodontics, and I believe it will serve as a milestone in the history of our specialty. Once more, on behalf of the audience, let me say, “ ‘Thank you. ’ ’