Stability of Orthognathic Surgery a Review of Rigid Fixation VanSickels British Journal of Oral and Maxillofacial Surgery 1996 34-4-279 285

8/12/2019 Stability of Orthognathic Surgery a Review of Rigid Fixation VanSickels British Journal of Oral and Maxillofacial Surg

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C 1996 The British Assoc~atmn of Oral and Maxillafacial Surgeons

REVIEW ARTICLEStability of orthognathic surgery: a review of rigid fixationJ. E. Van Sickels, D. A. RichardsonDepartment of Oral and Musillofucial Surgery: University of Texas, Health Science Center ut San Antonio,Texas, USA

SUMMARY. The use of rigid fixation with orthognathic surgery was greeted by both excitement and healthyconcern when it began to find its way into the literature approximately 10 years ago. The purpose of this paperis to review the literature and make comments based on the experience of the senior author on whether one of theearly premises was true. Has rigid fixation improved stabili ty with orthognathic surgery? The authors chose toexamine mandibular advancements treated with a bilateral sagittal split osteotomy and maxil lary osteotomiestreated with a Le Fort I osteotomy. When compared to wire osteosynthesis, rigid fixation has improved stability ;however, the individual move associated with the osteotomy must he considered. In some cases, auxil iary techniquesshould he used to ensure stabili ty. Condylar resorption with mandibular advancement continues to he an areaof concern.

In a relatively short period of time, the use of rigidfixation of bony segments in orthognathic surgeryhas become a standard of care. There are severalreasons for this change including shorter periods ofhospital stay and patient convenience. Minimal orno immobiliza tion of the jaws allows patients tofunction sooner, to resume their daily activ itiessooner, and return to work earlier. Earlier functionand airway management has changed hospital prac-tice. Procedures which had once been done in aninpatient environment are now being done as anoutpatient.1.2 Complex procedures that would havebeen difficult with wire osteosynthesis are easier toexecute with rigid fixation.3*4While rigid fixation has brought new poss ibilitiesto the treatment of dentofacial and craniofac ialdeformities, there are many questions that remain.Advocates of rigid fixation suggested that with rigidfixation one would change bone healing and eliminaterelapse.5 The question remains, With use of rigidfixation has stabil ity of common orthognathic surgi-cal procedures improved? The purpose of this paperis to review the existing data to determine if rigidfixation has improved stabil ity with routinely usedorthognathic surgical procedures for the mandibleand maxilla . Due to volume of articles available,selected papers have been chosen to illustrate pointsto be made. The first part of the paper is a criticalreview of the literature. The discussion and con-clusions section has more editorial comments, whichreflect the senior authors beliefs and practice. Thesurgical procedures that wil l be examined areadvancement of the mandible by a bilateral sagittalsplit osteotomy (BSSO ) and maxillary surgery witha Le Fort I osteotomy. These two procedures werechosen because they are the most frequently per-

formed operations, and the literature has the mostinformation regarding stabi lity with their use.

MANDIBULAR ADVANCEMENT WITH A BSSOA review of the literature on this topic is complicatedby several factors. There is considerable variabilityin the way that surgery is done between one surgeonand another. In addition, techniques used to stabilizesegments have considerable variab ility. Severa l tech-niques are considered under the broad term wireosteosynthesis. These include inferior border wire,circumferentia l wire, and superior border wire. Forthe sake of this paper these different stabilizationtechniques wil l be considered as one group. Where itis known, the specific technique wil l be mentioned.In a simi lar fashion, there are multiple techniquesthat are considered when the term rigid fixation isused. These include the use of a lag sc rew technique,position screws, and plates. This does not even con-sider the composition of the material used and thedifferent manufactures developing these materials.Additionally, there are different size screws andnumber of screws placed to stabilize the mandible.In this paper we wil l limi t our review to studies whereat least three screws per side were used and considerall 2 mm systems as similar.Short-term relapseStabi lity of mandibular advancements has been div-ided into short term and long term relapse.-9 Severalpapers noted that relapse with w ire osteosynthesisoccurred during and soon after maxillomandibularfixation.6x0. Schendel and Epker6 noted unaccept-

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able postsurgical results occurred more frequentlywith large advancements. The adverse movement ofosseous structures after surgery could be linear,rotary, or a combination of both. Most of the relapsethey noted occurred soon after the surgical procedure.Relapse which occurs during the first 6-8 weeks isknown as early relapse and is usual ly due to move-ment at the osteotomy site.Early relapse has also been seen with rigid fix-ation.12-15 Several studies with b icortical screwsshowed relapse is associated with larger advance-ments. In a paper by Gassmann, Van Sickels andThrashI it was noted that early relapse occurred atthe osteotomy site. They described linear and rotarychanges occurring at the junction of the proximaland distal segments accounting for the relapse. Theauthors speculated that large advancements placeincreasing amounts of stretch on the surrounding softtissue envelope. In addition, cases where there arelarger movements, have smaller amounts of bone atthe interface between the segments. Gassmann, VanSickels, and Thrash,15 suggested early relapse mightbe prevented with skeletal wires and a period ofmaxillomandibular fixation.Both animal and clinical studies have shown relapsecan be reduced by skeletal wires.6,16-9 In 1980,Schendel and Epker6 noted skeletal fixation preventedosseous relapse in cases with wire osteosynthesis. In1986, El lis and Gallo16 showed an insignif icant meanhorizontal relapse of 8.9 at pogonion in 20 patientsduring the period of fixation when skeletal wires werecombined with wire osteosynthesis and an eight weekperiod of fixation. Van Sickels looked at two groupsof patients undergoing large advancements both whohad three 2 mm bicortical screws placed at the oste-otomy site where one group had additional skeletalwires placed and were kept in maxillomandibularfixation for 1 week. He noted significant differencesbetween the two groups in the first 6 weeks and fromthe initia l postoperative period to the long termexamination point. He did note that while stabilitywas markedly improved with up to 13 mm ofadvancement in the group with screws and wires,relapse was seen with larger advancements. He specu-lated on the importance of the maxillomandibularfixation and whether using elastic traction betweenskeletal wires would be equally effective.Mayo and Ellis18 studied short term stabili ty ofthe mandible following advancement surgery in twogroups of animals, one with dental maxillomandibu-lar fixation and the second with skeletal suspensionwires plus dental maxillomandibular fixation withwire osteosynthesis. The study showed both hori-zontal and vertical movement was signif icantly betterin the group with skeletal wires and maxillomandibu-lar fixation. In a later study, by the same group, agroup of animals with wire osteosynthesis and skeletalsuspension, did equally well as a group that wastreated with bicortical screws.19Long-term relapseProgressive condylar resorption resulting in laterelapse has been noted by a series of authors.8,20-25

It has been defined as a change in shape of thecondyle from normal to finger shaped with loss ofheight and later decrease in posterior facialheight. 23,26 Its incidence has been reported to bebetween 2.3 and 7.7 of patients treated by a BSSOto advance the mandible.8~20~27 t has been seen withone and two jaw procedures where the BSSO wasstabilized with superior border wires, plates andbicortical screws.8,20,23,27,28 Radiographic signs ofcondylar resorption were first noted at 6 months ormore after surgery with a range of 6-17 months.27Additional relapse has occurred following secondarysurgeries.22,27,29 There are several theories as to whyit occurs. Kerstens et ~1.~ suggested that surgerystimulates a process in the bone by increased load onthe joint. They felt the process may be initiated bydisk displacement and immobilizat ion. Arnett et aL2*suggested that mediolateral torquing or posteriordisplacement of the condyle with rigid fixation maybe associated with condylar resorption and laterelapse. Ellis and Hinton3 sacrificed twelve animalswho had undergone a BSSO that was fixed witheither wires or bicortical screws. Animals who hadposterior displacement of the condyles showed evi-dence of resorption of the posterior surface of thecondyle and anterior surface of the postglenoid spine.They stated that alterations in condylar position mayinduce remodeling changes within the TMJ. Condylarresorption has been noted more frequently infemales with high mandibular planes, preoperativetemporomandibular dysfunction, large mandibularadvancement and distal segment counter c lockwiserotation.20,23,27 Scheerlinck et ~1.~ noted progressivecondylar resorption was four times greater foradvancements greater than 10 mm than for those foradvancements between 5 and 10 mm. Van Sickels17noted the group of large advancements that werefixed and further stabilized by suspension wiresshowed early relapse but were stable after 6 weeks.However, the group that only had bicortical screwsshowed both early and late relapse. Link andNickerson reviewed 38 patients who had some stageof internal derangement of temporomandibular jointprior to surgery. Fifteen of thirty patients with follow-up of greater than 12 months developed new arthrosisafter orthognathic surgery. All arthrosis occurred inpreviously deranged joints. They suggested that newloading of deranged joints after surgery may be acause of a new arthrosis and skeletal relapse.

COMPARISON PAPERSPlates versus position screwsSeveral authors have suggested that plates used tostabil ize the fragments may have an advantage overbicortical screws because they may minimize rotationof mandibular condyles.8,31 Stability with plates hasnot been investigated to the same extent as bicorticalscrews. Blomqvist and Isaksson32 compared short-term stability seen when two groups of patientsunderwent mandibular advancement using either


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Rigid fixation 281three bicortical position screws or monocorticalscrews and plates. They noted there was no differencein the stabil ity between the two groups. Both showedinstab ility the further the mandible was advanced.

Wire osteosynthesis versus hicortical screwsWatzke, Turvey, Phi llips and Proffit33 published apaper in 1990 where they evaluated the stabil ity oftwo groups of patients who underwent a BSS O formandibular advancement; one group was fixed byscrews and the second by wires. The authors do notsay whether either groups had suspension wires inaddition to their fixation technique. At 6 weeks aftersurgery, Points B and Pg came forward 2-4 mm in18 of the sample with screws. There was almost notendency for the mandible to slip posterior duringthis period. Eighteen percent of the sample hadsuperior movement of the mandibular incisor. Thewire group, in contrast, had 50 of the sample moveposterio rly 2-4 mm at 6 weeks. The mandibular planeincreased 2-4 degrees largely due to upward move-ment of gonion. When changes from pos tsurgery to1 year were analyzed, the differences between thegroups were not as obvious. In the screw group, Bpoint moved forward 0.33 mm and superiorly1.37 mm. There was considerable variability withinthe group. Pg moved forward in 25 of the groupand posterior in 20 of the group. In the wire group40 1of sample had posterior movement of Pg while15 of the sample had anter ior movement of thelandmarks. Overall there were simi lar movementsbetween the groups with the exception that there wasmore rotation of the proximal segment in the wiregroup than in the screw group.The study was complicated and, therefore, hard tointerpret because of several methodological flaws.While the majority of the surgery appears to havebeen done by one surgeon, different surgeons wereinvolved. Different techniques were employed in boththe screw and wire groups. The screw group had 21patients who had 2 mm position screws while 14 had2 mm lag screw technique or with 3.5 mm com-pression screws. The wire group had 27 patients whowere treated with a figure of eight superior borderwire, 2 with circumferential wires and 6 with superiorborder wires . Both groups were advanced similaramounts, screws 6.8944.4 mm at Pg and wires6.45 k 5.1 mm. However, the large standard devi-ations ind icate there were large advancements in bothgroups. While making overall comparisons easier,multiple previous studies have shown that earlyrelapse is more prevalent with large advancements.Relapse in some of the sample in each group wouldobscure subtle differences between the groups.At 6 weeks postsurgery, the authors noted thatsome patients had the splints stil l in place while theywere removed in others. Most l ike ly the patients whohad screws had their sp lints removed before 6 weekswhile those with wires still had them in place. Thiswould make the wire group look worse at 6 weeksbut improved at 1 year. The forward movement inboth groups was due to vertical settling when the

splints were removed and some occlusal changes.This data suggests there is more long term relapse/resorption in the rigid fixation group: however, dueto the multiple problems in the study design, thatconclusion can not be made with this paper.

MAXILLA-LE FORT IIn 1989. Larsen et ~1.~ noted there was very littledifference between maxilla stabilized by plates andthose stabilized by wires. However, they included avariety of moves in both of their groups. Maxi llarystabili ty cannot be studied without examining themovement that was attempted with the initia l surgery.ImpactionMost surgeons agree that maxil lary impaction is avery stable movement. Proffit et ~1.~~noted that thevertica l position of the maxilla was stable in approxi-mately 80 of patients who underwent superiorrepositioning of the maxilla and were stabilized withwire fixation. In a later study from the same insti -tution, 49 patients who underwent a minimum of2 mm impaction were followed for at least 5 years.They noted modest long-term skeletal and dentalchanges that were unrelated to the age of the patient,stabil ity during the first postsurg ical year, or segmen-tation of the maxilla at surgery. No rigid fixation wasincluded in this group.AdvancementIn 1987, Carlotti and Schende13 studied 30 patientswho underwent maxi llary advancement stab ilized bywire osteosynthesis. They had cases with both isolatedmaxil lary surgery and two jaw procedures. Eightcases had larger than desired postoperative move-ment. They attributed the undesirable movement topreoperative orthodontic flaring of the central inci-sors. They concluded that suspension w ires and bonegrafting were sufficient to obtain ske letal stability incases of maxil lary advancement up to 11 mm. Whensurgery is more complex, they recommended rigidfixation.Luyk and Ward-Booth38 reviewed their results in11 patients who underwent maxi llary advancementwith rigid fixation and intermaxillary fixation for 6weeks. The mean maxilla ry advancement in a hori-zontal direction was 3.7 mm. They noted there wasno significant relapse.Louis et ~1.~ studied maxi llary advancementin three groups of patients with obstructive sleepapnea who underwent bimaxillary advancement. Onegroup had their maxilla advanced an average of4.7 + 0.8 mm, the second was advanced 8.2 + 0.9 mm.while the third was advanced 12.3k2.8 mm. Allpatients had miniplates in the maxilla and bicorticalscrews in the mandible. There was sligh tly morerelapse as the maxillas were advanced; however, therewas no statistical differences between the groups.Egbert et ~1. compared two groups of patients


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282 British Journal of Oral and Maxillofacial Surgery

undergoing maxil lary advancement. This study isparticularly interesting because all surgeries weredone by the same surgeon. Twelve patients weretreated by wire osteosynthesis with intermaxillaryfixation for 4 weeks, and 13 had rigid fixation andtraining elastics for 4 weeks. Postsurgical horizontalchange for both groups was in a posterior direction.Comparison of the mean values between the twogroups suggested improved stability with rigid fix-ation; however, this difference was not statisticallysignificant. In contrast, there was a significant differ-ence between the two groups in the vertical directionwith the wire group showing more vertical sett lingone year after surgery.

SetbackWe did not tind any papers in the literature whichspecifica lly addressed the stability of an isolated groupof patients who underwent maxi llary setbacks. In thesenior authors experience, this particular move istechnically more difficult to execute; however, it isvery stable when plates are used to stabilize thesegments. Frequently, osseous gaps are present inthe anterior maxilla which require bone grafts to fillthe voids and give a scaffold for osseous regeneration.In contrast, with wire osteosynthesis, this type ofmove is prone to further upward movement.

InferiorInferior repositioning of the maxilla has been tra-ditionally very unstable.41-43 Quejada et aL4i notedthat over 50 of the relapse of maxil lary osteotomiesstabilized with wire fixation occurred during theperiod of maxillomandibular fixation and the remain-ing relapse occurred within the first 6 months aftersurgery. Hedemark and Freihoffer42 reviewed 12 casesof maxil lary surgery where the maxilla had beenbrought down and stabilized with wire osteosynthesis.Ten of the twelve moved upwards. They concludedthat the downward movement of the maxilla is especi-ally unstable and that one has to either overcorrector search for possibilities of stabilization other thanwire stabilization. Van Sickels and Tucker44 notedthat even with rigid fixation, maxilla which are pos-itioned in an inferior direction can be verticallyimpacted after surgery. Furthermore, postoperativemovement may result in a non union. Ell is et ~1.~~studied the stabi lity of inferior movement of themaxil la using different techniques to fix the maxilla.One group had wire fixation of the maxil la and bonegraft. The second had a similar procedure with theaddition of myotomies of the masseter and temporalismuscles. The third had a bite opening appliancebefore down-grafting. The fourth group underwentdown-grafting with rigid internal fixation. Al l of thegroups had relapse; however, the animals who under-went rigid fixation had the most stable results,followed by the myotomy and bite opening group.The least stable group was the one with wire osteo-synthesis and bone grafts.

Open biteOpen bite skeletal discrepancies can have a multitudeof causes. 45 Correct of an op en bite can be done bysurgery in the maxilla or mandible. Probably themost frequent correction of patients with open bitesis done by surgery in the maxilla. Stability of openbite cases corrected by maxillary surgery is probablyrelated more to the management of transverse prob-lems of the dentition and tongue problems that it isto anterior-posterior or vertical discrepancies or thehardware used to fix the maxilla.46*47There are cases where the stability of the maxillarysurgery is related to tongue size or tongue function.Frohlich et ~1.~~ tudied tongue pressures in 21 child-ren before and after surgical reduction of the tongue.Most of these subjects had either anterior or posterioropen bites present. They noted that 12 months aftersurgery resting tongue pressures were lower thanbefore the tongue reduction surgery, and were closerto those of a reference sample. A tongue reductionin selected cases may help close an open bite.Haymond et a1.47 etrospectively studied 38 patientswith skeletal pre-operative open bite treated withsmall plate internal fixation to assess surgical/ortho-dontic stability. Eighty-six percent of the sample hada stable result . Fifty percent of relapses were due totransverse relapse of orthodontically expanded maxil-lary arches. The authors concluded that stable resultscan be achieved in treating skeleta l open bite whensmall plate internal fixation is used and proper con-sideration given to the cause of skeletal open bitewhen planning.

DISCUSSION AND CONCLUSIONSFrom the preceding review it is evident that there aremany factors that need to be considered when examin-ing the question of stability. There are cases where itmakes no difference whether wires osteosynthesis orrigid fixation is used. There are others where it isclear that rigid fixation does improve stability. Thefactors which appear to have the most influence onstabi lity are whether the upper or lower jaw is beingmoved, which direction they are being moved, andhow much they are being moved. The followingsections will discuss upper and lower jaw surgery.The first conclusion that can be drawn for all surgicalprocedures is that whether wires osteosynthesis orrigid fixation is used, relapse can occur.

Mandibular advancement: early relapseEarly relapse occurring with the use of wire osteo-synthesis and a mandibular advancement has beenwell recognized with some authors reporting as muchas 90 relapse occurring during maxillomandibularfixation.6,7*48,4g This lead to a variety of suggestionsto minimize relapse including overcorrection of theocclusion, opening of the posterior bite, suprahyoidmyotomy, using a sternal mandibular brace, andskeleta l fixation in addition to maxillomandibular


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fixation.7,4sm51 Of these techniques, skeletal fixationand suprahyoid myotomy remain options to usewhenever the mandible is advanced, and stabi lity isin question. With the advent of rigid fixation it wasthought that relapse would be a problem of the pastdue to accelerated bone healing.s.52~53 Ell is et a1.s4studied 23 adult rhesus monkeys who underwentmandibular advancement by a BSSO fixed either bythree bicortical screws or wire osteosynthesis. Theresults showed that the two groups of animals under-went markedly different patterns of osseous healing.The osteotomy sites in the wire osteosynthesis animalswere filled with callus which then formed bone. Inthe rigid fixation sites there was direct bony depos-ition. It is important to remember that these sameanimals were used for stability studies and that thewire osteosynthesis group stabilized by skeletal wiresdid as well as the rigid fixation group. While theinitial premise was wrong, rigid fixation does giveimproved stability over dental fixation for smalladvancements. However, when dealing with largeradvancements, auxi liary techniques need to be con-sidered. Those that have efficacy are skeletal wiresand suprahyoid myotomy. The evidence for suspen-sion wires is clear from the previous discussion. Therole of maxillomandibular fixation is debatable.Evidence for suprahyoid myotomy is not as clear.Clinical studies have not shown a suprahyoidmyotomy to be effective.51 However, animal studieshave shown a suprahyoid myotomy to be effective.Most l ikely, a suprahyoid myotomy is not as effectiveas skeletal suspension wires but has a smaller effect.If screws cannot be used in a case, then one shoulduse an inferior border wire coupled with suspensionwires. From the paper by Watzke et a1.33 t is obviousthat superior border wire fixation does not controlthe proximal segment. In 1985 Singer and Bay?jcompared superior border wires to inferior borderwires used to stabilize a BSSO. They found that theinferior border wiring technique produced significantless antero-superior rotation of the proximal segmentand less increase in the gonial angle than the superiorborder wiring technique.Mandibular advancement: long-term relapseProgressive condylar resorption leading to long-termrelapse is now recognized as a small but importantcause of relapse in patients undergoing one or twojaw mandibular advancements. The associationbetween pre-existing temporomandibular symptomsand condylar resorption may suggest the need todelay surgery on symptomatic patients. The associ-ation between large advancements and condylarresorption suggests that early increased load leads tolate condylar resorption/remodeling. Perhaps thesame techniques used to prevent early relapse maybe helpful to prevent long-term relapse. It is interes-ting that Van Sicke ls17 did not see long-term relapsein his patients who had large advancements fixed bybicortical screws which were supplemented by skeletalwires and maxillomandibular fixation.The argument over plates versus screws is probably

more academic than factual. Both short-term andlong-term relapse appear to be similar whether screwsor plates are used. Both have problems the furtherthe mandible is advanced. That condylar torque canoccur with bicortical screws is a distinct possibility.However, it remains to be seen if there is a greaterincidence of temporomandibular symptoms withplates versus bicortical screws. Whether nerve injuriesare any more frequent when bicortical screws areused remains to be seen. In the senior authorspractice, bicortical screws are routinely used for man-dibular advancements, while plates are used for set-backs, large advancements, and asymmetry cases.This practice is based more on practical and technicalexperience than scientific data. Whi le lag screws havebeen used to fix a BSSO. laboratory work has notshown them to be more effective than positionscrews.5.57 Foley et a1.57 demonstrated there was nosignificant difference in rigid ity between compressionand bicortical screws for a BSSO. They did showthat an inverted L pattern was signif icantly morestable than screws placed in a linear fashion. Whetherit is better to use an inverted L pattern for largeadvancements is unknown. The senior author believesthis only puts more load on the condyles. Therefore,it is our practice not to use a lag screw technique orinverted L pattern for large advancements but tosupplement bicortical screws with skeletal suspen-sion wires.

MAXILLARY OSTEOTOMIES

As the literature search reveals, the maxilla behavesvery differently depending on how it is moved.58 Formaxillary impaction, the surgical move is very stable,and very small hardware is necessary to stabilize themaxilla. There is sparse data on setbacks of themaxilla; however, as mentioned earlier i t is ourimpression that this is also a very stable move. Thesize of the hardware is dependent on whether a bonygap exists after the surgical move. Advancement ofthe maxilla and especially inferior movement of themaxilla is not as stable as the two previous moves.58It is with these two moves that r igid fixation has beenshown to be superior to wire osteosynthesis. Withboth of these moves larger and stiffer plates need tobe used.Maxillary advancements stabilized with rigid fix-ation are more stable than those stabilized with wireosteosynthesis; however, are susceptible to relapsewith larger moves. Frequently, prior to surgery,dental compensations are sti ll present secondary totongue and lip pressures. In our practice it is commonto advance the maxilla at least 2 mm more than anideal overjet. This is to compensate for dentaldeficiencies and relapse. Orthodontically it is easierto orthopedically retract an advanced maxilla than itis to try to hold one that i s relapsing into an end toend incisor situation, Alternatively, one could use aperiod of maxillomandibular fixation. In the paperby Luyk and Ward-Booth38, three of their patientshad cleft lips and palates. Due to the scaring in the


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284 British Journal of Oral and Maxiilofacial Surgery

palate, advancement of the maxilla is more difficult.Welch58 suggested that a Le Fort I advancement in acleft palate patient was extremely unstable. However,a recent paper by Ayliffe , Banks and Martins9 showedplate fixation was superior to extraoral frame sup-plemented by intermaxillary fixation in a large seriesof cleft palate patients. In the experience of the seniorauthor, rigid fixation in addition maxillomandibularfixation for a period of 3-4 weeks is helpful to preventrelapse in these cases.

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Knoff SB, Van Sickels JE, Holmgreen WC . Outpatientorthognathic surgery: Cr iter ia and a review of cases. J OralMaxi l lofac Surg 1991; 49: 117-120.Van Sickels JE, Tiner BD . A com bined Le Fort I and bi lateralzygoma tic osteotomy for management of midface andmaxi l lary deficiencv. J Oral Maxi l lofac Surg 1994; 52:327-331: 4.

Inferior movement of the maxilla is one of themore challenging moves that can be made with themaxilla. While rigid fixation is clearly superior towire osteosynthesis, it does not assure absolute stab-ility. It is important to note in the paper by Ell is,Carlson and Frydenlund43 that while the rigid fixationgroup did the best, all of the groups had relapse. Thegroup that had myotomies did better than the wireosteosynthesis group alone. For large inferior move-ments, myotomies may be necessary as an adjunct tothe surgical procedure. Alternatively, as suggested inthe paper by Van Sickels and Tucker,44 additionalrigid pins going from the superior aspect of themaxilla to the splint may help stabilize a case wherethe maxilla was moved in an inferior direction.

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Schm itz JP, Tiner BD, Van Sickels JE. Stabi l ity ofsimultaneously Lefort I I I /Le Fort I osteotomies.J Craniomaxi l lofac Surg (accepted).Spiessl B. The sagittal spl it t ing osteotom y for correction ofmandibular prognathism. Cl in Plast Surg 198 2; 9: 491-507.Schendel SA, Epker BN. Results after mandibularadvancemen t surgery: an analysis of 87 cases. J Oral Surg1980; 38: 2655282.Epker BN, Wessberg GA. Mechanisms of ear ly skeletal relapsefol lowing surgical advancement of the mandible. Br J OralSurg 1982; 20: 172-176.Scheer l inck JPO, Stoel inga PJW , Bl i jdorp PA, Brouns JJA,Ni js MLL. Sagittal spl i t advancement osteo tomies stabi l izedwith miniplates. A 2-5 year fol low-up. Int J Oral Maxi l lofacSurg 1994; 23: 127-131.El l is E, Car lson DS. Neuromuscular adaptation afterorthognathic surgery. Oral Maxi l lofac Surg Cl in N Am 1990;2:811-830.10.

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Stability of the maxilla cannot be discussed withoutnoting if there were additional mandibular movement.Several authors have noted with wire osteosynthesisthat when the mandible was advanced, it had anadverse effect on maxil lary position.60s61 In 1988Skoczylas et a1.62 compared the resul ts seen in twodifferent groups of patients who underwent maxi llaryimpaction with mandibular advancement. Fifteenpatients had skeletal plus dental maxillomandibularfixation, and fifteen had rigid internal f ixation usingbone plates in the maxilla and bicortical bone screwsin the mandible. The authors found no stat istica llysignificant difference between the experimentalgroups. However, the amount of variability in post-surgical stability in the group with skeletal plus dentalmaxillomandibular fixation was greater than thatfound in the group with rigid internal fixation. In thesenior authors experience, an unstable result occursin two jaw cases fixed with rigid fixation when themandible is advanced large amounts. When a case isset up for a large advancement, large stiff plates areused on the maxilla combined with suspension wiresand a brief period of maxillomandibular fixation.

Kohn MW . Analysis of relapse after mandibular advancementsurgery. J Oral Surg 1978; 36: 676-684.Smith GC, Moloney FB, Wes t RA. Mandibular advancemen tsurgery. A study of the lower border wir ing technique forosteosynthe sis. Oral Surg Oral Med Oral Path01 1985; 60:467-475.12.

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Van Sickels JE, Larsen AJ , Thrash WJ . Relapse after r igidfixation of mandibular advanceme nt. J Oral Maxi l lofac Surg1986; 44: 6988702.Van Sickels JE, Larsen AJ, Thrash W J. A retrospective stud yof relapse in r igidly f ixated sagittal spl i t osteotomies:Contr ibuting factors. Am J Orthod Den tofacial Orthop 1988;94~413-416.14.

15.16.

17.

Kirkpatr ick TB, Woods MG, Sw ift JQ, Markow itz NR.Skeletal stability following mandibular advan ceme nt and rigidfixation. J Oral Maxi l lofac Surg 1987; 45: 5722576.Gassamann CJ, Van Sickels JE, Thrash WJ . Cause s, locationand timing of relapse following rigid fixation after mandibularadvancem ent. J Oral Maxi l lofac Sum 1990: 48: 450-454.El l is E, Gal lo JW . Relapse fol lowing-mandibular advancemen twith dental plus skeleta l maxillomandibu lar fixation. J OralMaxi l lofac Surg 1986; 44: 509-515.Van Sickels JE. A compa rative study of bicortical screws andsuspension wires versus bicort ical screws in large mandibularadvancem ents. J Oral Maxi l lofac Surg 1991; 49: 1293-1296.18. Mayo KH, El l is E. Stabi l i ty of the mandible afteradvancement and use of dental plus skeletalmaxillomandibu lar fixation : An experime ntal investigation inMacaca mulatta. J Oral Maxi l lofai Surg 1987; 45: 243-250.19. El l is E. Revnolds S. Car lson DS. Stabi l i tv of the mandiblefol lowing advancem ent: A comparison of three postsurgicalf ixation techn iques. Am J Orthod Dentofacial Orthop 1988;94:38&42.

Open bite deformity illustrates that it is moreimportant to understand the underlying skeletal prob-lem than what type of hardware is being used. Theadvent of rigid fixation has helped markedly in treat-ing this skeletal discrepancy. No more is it necessaryto do two jaw surgeries to close an open bite.45However, allowing extensive orthodontic expansionto eliminate multiple segmental surgery is setting thepatient up for vertical relapse, no matter how rigidthe fixation appliances are.47

20. Kerstens HCJ, Tuinzing DB, Golding RP, van der Kwas tWA M. Condylar atrophy and osteoarthr i t is after bimaxi l larysurgery . Oral Surg Oral M ed Oral Path 01 1990; 69: 274-279.2 1. Phi ll ips RM , Bel l WH . Atrophy of mandibular condyles aftersagittal ramus spl i t osteotom y: report of a case. J Oral Surg1987; 36: 45549.22. Crawford JG, Stoel inga P JW, Bl ijdorp PA, Brouns JJA.Stability after reoperation for progress ive condylar resorptionafter or thognathic surgery: report of seven cases. J OralMaxi l lofac Surg 1994; 52: 460-466.23. Merkx MA W, Van Damm e PA. Condylar resorption afterorthognathic surgery. J Craniomaxi l lofac Surg 1994; 22:53-58.

References 24. Huang CS, Ross BR. Surgical advancemen t of theretrognathic mandible in growing children. Am J Orthod 1982;82:89-95.1. Tucker M R. O rthognathic Surgery versus orthodontic 25. Sesenna E, Raffaini M. Bi lateral condylar atrophy aftercamouflage in the treatment of mandibular deficiency. J Oral combined osteotom y for correction of mandibular retrusion.Maxi l lofac Surg 1995; 53: 572-578. J Maxi l lofac Surg 1985; 13: 263-267.


7/7

26. Arnett GW, Tambore llo JA. Progressive class II developm ent:female idiopathic condylar resorption. Oral Maxillofac SurgClin North Am 1990: 2: 699-705.

27. Moore KE, Gooris PJJ, Stoelinga PJW. The contributing roleof condylar resorption to skeletal relapse followin gmandibular advancement surgery. J Oral Maxillofac Surg1991; 49: 448-460.

28. Arnett GW, Tamborello JA, Rathbone JA.Temporomandibular joint ramifications of orthognathicsurgery. In: Be ll WH, ed. Modern Practice in Orthognathicand Reconstructive Surgery, Vo l I, Philadelph ia: WBSaunders, 1992: 523-593.

29. Link JJ. Nickerson JW. Temp oroma ndibular join t interna lderangem ents in an orthognathic surgery popula tion. IntJ Adult Orthod Orthog Surg, 1992; 7: 161~ 169.

30. Ellis E, Hinton RJ. Histologic examination of thetemporomandibular joint after mandibular advancement withand without rigid fixation: A n experimental investigation inadult macaca mulatta. J Oral Maxillofac Surg 1991: 49:

31.

32.

13_.

34.

35.

36.

37.

38.

39.

40.

41.

42.

43.

44.

45.

46.

47.

1316-1327.Tulasne J-F, Schendel SA. Transoral placement of rigidfixation following sagittal ramus split osteotomy. J OralMaxillofac Surg 1989: 47: 651-652.Bomqvist JE, Isaksson S. Skeletal stability after mandibularadvancement: A comparison of tWo rigid internal fixationtechniques. ? 1994; 52: 1133-I 137.Watzke IM. Turvey TA, Phillips C, Proffit WR. S tability of(mandi bular advancem ent after sagittal osteotomy with screwor wire fixation: A comparative study. J Oral Maxillofac Surg1990: 48: 108&121.Larsen A J. Van Sickels JE, Thrash WJ. Postma xillary stability:A comparison study o f bone plat e and screw vs wire osseousfixation. Am J Orthod Dentofacial Orthop 1989: 95: 334-343.Proffit WR. Phillips C. Turvey TA. Stability following superiorrepositioning of the maxilla by Le Fort I osteotomy. AmJ Orthod Dentof acial Orthop 1987: 92: 151-161.Bailey L, Phillips C. Turvey TA. Stability following superiorrepositioning of the maxilla by Le Fort I osteotomy: Five yearfollow-up. Int J Adult Orthod Orthog Surg 1994; 9: 163-I 73.Carlotti AE. Schendel SA. An analysis of factors influencingstability of surgical advancement of the maxilla by the Le FortI osteotomy. J Oral M axillofac Surg 1987: 45: 924 ~928.Luyk N H, Ward-Booth RP. The stability of Le Fort Iadvancement osteotomies using bone plates without bonegrafts. J Maxillo fac Surg 1985; 13: 250-253.Louis PJ. Waite PD, Austin RB. Long term skeletal stabilityafter rigid fixation of Le Fort I osteotomies with advancement.Int J Oral Maxillofac Surg 1993: 22: 82-86.Egbert M. Hepworth B. Mydall R, West R: Stability of LeFort I osteotomy with maxillary advancement: A comparisonof combined wire fixation and rigid fixation. J Oral MaxillofacSurg 1995: 53: 243.-247.Quejada JG, Bell WH. Kawamurd H, Zhang X : Skeletalstability after inferior maxillary repositioning. Int J AdultOrthod Orthog Surg 1987; 2: 67-74.Hedemark A. Freihoffer HP. The behaviour of the maxilla invertical movemen ts after Le Fort I osteotomy. J Maxillo facSurg 1978: 6: 2444249.Ellis E. Carlson DS, Frydenlund S. Stability of midfidceaugmentation: An experimental study of musculoskeletalinteraction and fixation methods. J Oral Maxillofac Surg 1989;47: 1062m 1068.Van Sickels JE, Tucker MR. Management of delayed unionand nonunion of maxillary osteotomies. J Oral ManillofacSurg 1990; 48: 1039-1044.Joos U. Surgical management of skeletal open bite by ramusosteotomies. In: Bell WH. ed. Modern Practice inOrthognathic and Reconstructive Surgery, Vol 3. Philadelphia :WB Saunders. 1992: 2060&2109.Frohlich K, Ingervall B, Schmoker R. Influence of surgicaltongue reduction on pressure from the tongue on the teeth.Angle Orthod 1993: 63: 191- 198.Haymond CS, Stoelinga PJW, Blijdorp PA. Leenen RJ,Merkens NM. Surgical orthodontic treatment of anteriorskeletal open bite using small plate internal fixation. One to

48.

49.50.

51.

52.

53.

54.

55.

56.

j7,

58

59

60

61

62

five year follow-up. Int J Oral Maxillofac Surg 1991: 20:223-227.Poulton DR. Ware W. Surgical-orthodontic treatment ofsevere mand ibular retrusion. 1. Am J Orthod 1973: 63:237-242.McNeil] RW. Hooley JR. Sundberg RJ. Skeletal relapseduring intermaxillary fixation. J Oral Surg 1973: 31: 212 227.Steinhauser EW. Advancement ofthe mandible by sagittalramus split and suprahyoid mq otomy. J Oral Surg 1973: 3 I:516 521.Wessberg GA. S chendel SA, Epker BN. The role ofsuprahyoid myotomy in surgical advancement of the mandiblevia sagittal split ramus osteotomies. J Oral Maxillopdc Surg1982; 40: 273-277.Jeter TS, Van Sickels JE. Dolwick MF. Modified techniquesfor interna l fixation of sagittal ramus osteotom ies. J OralMaxillofac Sure 1984: 42: 270-272.McDonald W

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Stability of Orthognathic Surgery a Review of Rigid Fixation VanSickels British Journal of Oral and Maxillofacial Surgery 1996 34-4-279 285