The Labiobuccal RetainerPAUL D. LEWIS, D.M.D."Seattle, WashingtonIn the past several years many phasesof orthodontics have received increasedattention, such as appliance technics,cephalometric diagnosis, and treatmentplanning, to mention but a few. Thiscertainly is as it should be - it is ad-vancement, it is progress - and few,if any, would have it otherwise. Thestudy of retention, however, has hardlykept pace. Emphasis has not been plac-ed upon the problems of retention, andmaybe that is why it has been ratheraptly called the "step-child" of ortho-dontics.A study of the problems of retentionhas long been of special interest to thewriter. Foremost among retentionproblems are how to maintain the teethin function and in their new positions,and how to prevent relapses. How to dothis successfully is what I would liketo discuss with you, and I hope youcan benefit from some of my ex-periences. Do we always get perfectresults? No, naturally not, but the per-centage of stable end results has in-creased markedly.Retention is a subject that cangenerally be discussed in most ortho-dontic circles because, regardless ofwhether one is a one hundred percenter or occasionally extracts bicuspids,retention of one's cases is a problemto most of us. It is one of the so-called"facts of life'' that eventually faces usin the majority of our cases.Someone once said that orthodonticsis a science but retention is an art. ThatPresented at the Biennial Meeting of theEdward H. Angle Society of Orthodont.ia,Washington, D. C., October, 1957.*Clinical Associate, Department of Ortho-dontics, University of Washington.the science of orthodontics can betaught is quite self-evident, but I havefelt for a long time that the art of re-tention cannot be taught easily but issomething that has to be tried againand again by most men before it isunderstood and mastered. It is a con-stant battle - making teeth remainin new positions and function thereafter bands and appliances are remov-ed.Quite recently a good orthodonticfriend of mine asked me, "Why is itthat my cases, which look so good tome as they become ready for retention,too often look so poor in retentionwhen it should be just the reverse?"Years ago I heard an old orthodonticsaying that went like this, "I'll treatthe case, you retain it, and I'll give youhalf the fee." Many of you, I am sure,can recall having heard this and, eventhough it is a little unrealistic, it stillexpresses well the apprehension thatmen have had and continue to havefor this very important but often neg-lected phase of our work.There is more than one school ofthought regarding the subject of re-tention. A poll taken at a recent meet-ing showed the older members asfavoring formal retention for theircases while the younger men presentwere less interested in retaining casesafter treatment. Was this because theolder men, who had practiced moreyears, had witnessed too many of theirown well-treated cases relapse from lit-tle understood or careless retention ontheir part?Let us discuss for a few minutes whatI feel are fallacious lines of reasoningwith regard to this subject. The first1 2LewisJanuary, 1959one is this: "If malocclusions are ideallycorrected, the forces of the inclinedplanes will be sufficient to balance thedenture, and formal retention will notbe necessary."I do not believe that many of theyounger men, and surely none of theolder, will accept this one-time ratherpopular theory. To anyone inclined to-ward this line of thinkins, one has onlyto remember that osteoid-type bone isa very poor substitute for mature bonein holding teeth in their proper placeswhile withstanding the muscularstresses and forces of occlusion that arealways present even during retention.Some form of support or splint isnecessary in most cases after band re-moval to support the teeth until bonetissue is reorganized.The second line of reasoning is this,and again I am addressing myselfprincipally to the younger men. Whyretain, is the attitude of some menwhose rather logical argument is, "Iflater why not have them do it sooner?In short, let's get on with the relapseand see how bad it is going to be." Thatactually was the attitude of a group ofmen I talked with not too long ago. Ithink in general we would agree thatthis is faulty reasoning. Why go to allthe trouble and expense of doing thework just to let the teeth relapse? Toomany successfully treated and retainedcases testify to the benefits of wellplanned and carried out retention toaccept such a faulty argument.For many years there has been aneed for something better than whatwe have had for maxillary retention incertain types of cases. I refer morespecifically to the treatment of ClassI1 cases in which a considerableamount of intermaxillary elastic trac-tion has been necessary. Retention ismost generally a problem with thechild who has had a Class I1 maloc-clusion, a hypotonic upper lip, andrL- --*L --- ,.-.-,. e, .._ O.,r_lllt: tCCL11 alc s;V;.y L" *L!cApL SGGZPP OPwho, because of habit or allergy, can-not or will not use his lips correctly.In such cases Class I molar relation-ship, attained through the use of rub-ber elastics and headgear wear, is oftenimpossible to hold or maintain duringretention. During retention, the maxil-lary teeth too often move forward againfollowing the removal of the distalrestraint, and are followed by themandibular teeth which attempt to re-main in Class I relationship. The lowerteeth fit better in a forward position,and the patient may also realize helooks better with his lower jaw for-ward; thus a convenience bite is start-ed, a dual bite is created. Many timesin these once protrusive cases, the bestof ordinary retainers are not capableof holding the maxilla in Class I oc-clusion.At the 1952 Tweed meeting inChicago, during a symposium on re-tention, I described the use of the .045archwire, with an auxiliary spring andon the teeth of the maxillary arch. Thiswas termed active retention. Thoughnot perfect, this approach proved to bea step in the right direction because itemployed the use of a distally directedforce on the maxillary teeth as theinitial step of retention after band re-moval. The effect of this archwire onthe teeth anterior to the molars wasnot ideal in all cases because it wassometimes difficult to close open con-tacts in the bicuspid and cuspid xgion,even in conjunction with a headgear.Neither did the combination of wear-ing a maxillary retainer by day and an,045 archwire with headgear by nightseem to be the answer in some of theseonce protrusive Class I1 cases. Theproblem was: how to get these stub-born retention cases out of one's prac-tice.In an effort to prevent the creationof a dual bite from developing and toassist in maintaining the Class I buccalhe.rdgc.rr, ~howigu itc -__ i.Pctva;njnu --I--- __. Pffrrt Vol. 29, No. 1Retainerrdationship established during treat-mcnt, I would like to discuss with youa method or approach to retention Ihave been using for quite some time.When basic treatment of a case hasbeen completed, that is, when the caseappears to be practically finished, aninspection tour is started before anybands are removed to determine ifthe case is ready for retention. Thefollowing points are checked :1. Has the overbite been adequatelyreduced?2. How about the mesiodistal rela-tionship of the teeth in the buc-cal segments? Are these teeth real-ly in Class I occlusion?3. Have the maxillary cuspids beencarried fully back to the bicuspidsso that they are in their correctrelationship to the lower cuspids?1. Examine the upper six year molars- have they been rotated suf-ficiently, or are the mesiobuccalCLISPS still rotated to the lingual?5. Do bicuspids, cuspids, or incisorsneed more rotation?6. If our case has been one in whichteeth had to be removed, it iswise to check to see if the rootsadjacent to the extraction areasare parallel.7. Check also to see if the roots ofthe upper centrals and lateralshave been torqued lingually anadequate amount.8. Is there a dual bite?If all these points check out favor-ably, then retention is started. It takesonly a fc.w minutes to make this in-spection tour and you may be sure itpays to do it before many bands areremoved because these same steps aredifficult and, in some instances, im-possible to do with retainers after thebands have been removed.It will probably be conceded thatClass TI extraction cases, as a rule,present more problems, both in treat-ment and retention, than non-extrac-tion cases. Therefore, Ict LIS discusssome of the preliminary steps in theretention of a Class I1 case in which itwas necessary to remove four firstbicuspids.Generally, the lower second bicuspidbands are the first bands to be removed.The bands on the six anterior teethare lightly stripped with lightning stripsto reduce band thickness at the con-tact points. Small coil spring sections(%" in length) are placed on the arch-wire mesial to the second molars andare tied back. Light Class I1 elasticsare worn to move the first and secondmolars forward, closing the secondbicuspid band spaces. Next, the firstmolar bands are removed and again thecoil spring sections are tied back to thesecond molars, and light Class 11elastics are worn closing the first molarband spaces. When the cuspid bandsare removed at the next appointment,Class I1 elastics are discontinued andthe coil spring sections removed fromthe archwire.The archwire at this point is usuallyretied for at least one week before thelower incisor bands are removed. TheClass 111 elastic hooks may be bentdistally until they rest lightly on thelower cuspids if expanded intercaninemeasurements prove this to be neces-sary. Just a very little pressure is need-ed at this time to narrow these twoteeth toward the original intercaninewidth.The four lower incisor bands arefinally removed and only slight spacesremain between these four teeth. Thelower archwire is checked for archform and then is ligated lightly to thesecond molars. The archwire is bentaway from the cuspids to preventmoving these teeth too far lingually,but rests lightly against the four incisors.The spaces between the anterior teethclose very quickly and the contactsbetween the cuspids and second bi-cuspids are maintained by this slight 4LewisJanuary, 1959pressure from the archwire. We are inno hurry at this time to make a lowerretainer. The archwire remains on fromone to three weeks before a lower im-pression is taken and sometimes anotherweek before the retainer is placed. Thisis as good a way as I know to keepextraction spaces from opening, helpcontacts to close, and maintain lowercuspids at their proper intercaninewidths.Let us recap for a moment. WhenClass I occlusion has been attainedand our case appears ready for reten-tion, a thorough inspection is made.Next, the lower bands are removed inpairs so that band space can be gradu-ally closed by light elastics worn be-tween appointments. When band re-moval is followed this way, correct archwidth can be regained in the molar,bicuspid and cuspid areas. This pro-cedure also allows the mandibular buc-cal teeth to return to a more favor-able buccolingual inclination. Lowerarch form is improved, contacts areclosed, and intercanine width correctedbefore the impression is taken for alower Hawley retainer. In short, overexpansion, open contacts, band spaces,and the too vertical axial positioningof the buccal teeth are not maintainedand perpetuated by placing a lowerretainer too soon.During the time lower band removalis under way the headgear is being wornagainst the maxillary teeth fourteenhours per day. This is very importantand cannot be overemphasized. Thesecond bicuspids are the first upperbands to be removed and follow veryshortly the removal of the lower bi-cuspids. As in the lower arch, the up-per first molar bands are removednext, in the event the second molarscarry the anchor bands. At a later ap-pointment the cuspid bands are remov-ed and finger springs are soldered tothe archwire to tuck the cuspids in andback in contact with the second bicus-pids. When the upper anteriors havebeen carried back as closely as possibleto the retained lowers by the action ofthe headgear, the four upper anteriorbands are removed and upper andlower impressions are taken for thepurpose of making a new type of maxil-lary retainer which I have called thelabiobuccal retainer.The technic for the construction ofthis new type of retainer is as follows:Upper and lower alginate impressionsare taken, together with a wax bitein centric occlusion. All loose and opencontacts in the maxillary arch are re-corded in writing. When the modelsare poured and trimmed, Fig. 1 above,a typical positioner set-up is made onthe upper model only. Generally, aminimum number of teeth have to bechanged on the maxillary set-up due tothe care with which band removal andspace closure has been followed inboth upper and lower arches. (Fig. 1center).Wire ciasps are bent to iay acrossthe labial of each central and to engagetheir distal surfaces above the contactpoints. Similar clasps engage the labialand distal of the laterals. (Fig. 1 bot-tom) The clasps gripping the distal ofthese four anterior teeth afford reten-tion for the appliance when it is fittedand worn on the maxillary teeth.The retainer is constructed on thelabial and buccal surfaces of the maxil-lary model, using fast-setting acrylic.Two small squares of plexiglass are im-bedded in the acrylic as it is settingon the labial surface, just distal to thecentrals. Holes are bored in these plexi-glass blocks to receive the headgearhooks later. After setting one-half hourthe retainer may be removed from themodel, trimmed and is then ready fora try-in. (Fig. 2)In December, 1954, a positioner set-up was made for a retention patientwho had once been very protrusive.It was a non-extraction case, and the-. .. Vol. 29, No. 1Retainer 5the maxillary teeth. It was placed inthe patient's mouth and she was in-structed to place it in her mouth andpush on it with her fingers for one-halfhour before retiring, and, of course, tosleep with it in her mouth as well.Little or nothing was expected of thisappliance when it was placed. It wasthought of as a one hundred to oneshot! The patient was seen at infre-quent intervals and, even though themolar relationship improved and be-came quite stable through wearing thiscrudely made appliance, little sig-nificance was attached to it at first.Months would go by between visits,and yet, this once protrusive non-ex-traction case that had developed a dualbite improved. It became stable.Finally, I began to wonder if thisFig. 1 Abovc, Casts after band removal.Center, resetting of some maxillary teeth,reducing overjet. Black lines indicate ap-proximate position of plexiglass hooks. Bot-tom, models w:.xcd together with wire claspsdistal to upper laterals and across centrals.Tinfoil is cemented to prevent acrylic fromseeping between teeth.Class I molar relationship in retentionwas slipping. Due to the unstable oc- Fig. F'inished retainer trimmed 8o it willelusion of this case, an attempt was not touch mandibular teeth. Correct positionmade to fabricate an appliance of of plexiglass hooks should be noted. Below, lingual position of the wires around centralsing the labial and buccal surfaces of and laterab.acrylic on the positioner set-up, cover-view showing P1~igl~S hook6 and 6 Lewisrather simple device might not be justas effective on other cases as well.Gradually and cautiously more weretried on different types of cases, ex-traction and non-extraction, which haddefinitely slipped during and after re-tention. Some had slipped a little,others more. All of them were helpedby the use of this new type of re-tainer. Then it was used on cases im-mediately out of treatment with equallygood results.At first, finqer pressure alone wasdepended upon as the source of powerto be applied to this new retainer. Itwas definitely felt that some sort ofpower or pressure was necessary tomake the appliance really effective. Itwas also felt that if in some way theheadgear could be applied to this re-tainer, it could become far more ef-fective in its purpose of retaining andrestraining the maxillary teeth in theseonce protrusive cases. Several differentways were tried in attaching the head-gear hooks; finally, it was fniind ~!iattwo small pieces of plexiglass, im-bedded in the acrylic as it was curing,could be shaped later so they wouldprovide suitable hooks from which toattach the headgear. (Fig. 3)Each time the labiobuccal retainerhas been used, molar, bicuspid andcuspid relationships have been main-tained or improved to the extent thatthe teeth have rapidly assumed a finish-ed look about them. Overjet has im-proved in all cases in which the bandshad just been removed; the degree ofoverjet achieved in active treatmenthas been maintained by the applicationof the labiobuccal retainer.A headgear has been worn on all butthe first few cases on which this retainerhas been used. Finger pressure wasused on the first cases with good suc-cess, but the headgear has proven to bemuch more effective. When the oc-clusion settles in good Class I molarrelationship and there appears to be noJanuary, 1959Fig. 3gwr :ttt:ichrd.A wt;~iiier in the month with hew-tendency to change, the headgear .timeis gradually decreased to every othercontinued. Naturally, when treating aClass I1 case, or any case in which pro-truding teeth have been a problem,more precaution is exercised and greaterlength of time is necessary before theheadgear may be discontinued.At the time the labiobuccal retaineris being constructed for the upper, aconventional Hawley type retainer ismade and worn on the lower arch.When retention of the lower arch hasbeen approached as has been described,the lower teeth need the lingual sup-port of a Hawley type retainer. It maybe a wise precaution after wearing thismandibular Hawley type retainer forsix months to change to a cuspid tocuspid fixed or soldered retainer. Thisprocedure is routine in our practice.It has been our experience that pa-tients do not object to wearing thisnew type retainer and there is littleobjection to the headgear either. Thepatients especially appreciate the free-xight, then twice 2 s:'ee! , etc., then dis- Vol. 29, No. 1 Retainer 7dom and ability to talk with this ap-pliance in their mouths, even whilewearing the headgear. Another featureworth mentionin? is that of cleanli-ness. Everyone occasionally has had theexperience of removing Hawley retain-ers and, with a sickening feeling, notingthe damage to hard and soft tissues inthe mouths of some careless patients.The labiobuccal retainer minimizesmuch of the chance of this damage inthe maxillary arch.The maxillary Hawley type retainer,situated as it is on the inside of the up-per arch, many times retains and main-tains overexpansion, loose contacts, andspaces, when it is used immediately af-ter band removal unless carefullywatched and constantly modified. Onthe other hand the upper arch is farbetter when the labiobuccal retaineris used because the restraining action ofthe retainer, plus the active force ofthe headgear, is directed from the buc-cal and labial zegments of the maxillaryarch, instead of from the lingual, thusinducing tight contacts, better overbiteand overjet, and improved occlusion.When one is dealing with an allergicpatient or one with a short upper lipand flabby musculature, the labiobuc-cal retainer ideally supplies the re-straining pressure which is so oftenlacking in these cases.This method of retention is consistentwith accepted descriptions of the forcesof occlusion. Moorc ha; dexribed theseforces as follows: "The buccinator andthe superior constrictor are a contin-uous band of muscle surrounding theentire denture, being attached poste-riorly to the spinal column. Thesemuscles can thus be considered as anelastic force surrounding the entiredenture and being responsible formolding the maxillary denture againstthe lower contained mandibular arch.In order to summarize the functionalforces of occlusion, it may be statedthat generally speaking these forcescreate a buccal and labial force uponthe maxillary denture and a lingualforce upon the mandibular denture.It should be emphasized that themandibular arch form is determinedprimarily by the lingual forces createdby function. The contact of the man-dibular teeth with one another producea contained arch around which thebuccinator muscle and the incline planerelationship of the teeth mold the max-illary denture."This new type of maxillary retentionhas been used successfully in well overone hundred cases in our office. Insome instances it has been the onlymaxillary retention used. After thelabiobuccal retainer has been wornfor awhile, after the overjet has beenreduced, and the contacts closed, wehave found it beneficial in many casesto use a maxillary Hawley type retainerduring the daytime to hold the fourincieors together and to assist in main-taining the overbite.What I have attempted to tell youis that if retention is started on thelower arch first, if all the band spacesin the lower arch are closed and heldclosed as described above, then it ispossible to get the maximum from thelabiobuccal retainer. The architec-ture of the lower arch should and canbe very close to what is meant for thatindividual befor? a lower retainer ismade. It is then that the teeth in themaxilla can be moved back and drapedaround the retained lower most ef-fectively for better retention.121.5 4th Avenue