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1、UnitTwentySeven LeForteIosteotomyforcorrectionofmaxillarydeformitiesWilliamH.Bell,DDS.Dallas Completemobility,preservationofviability,andadequatefixationduringhealingisessentialtosurgicalrepositioningofthemaxillatoobtainastablerelationshipwiththemandible.LeForteIosteotomytechniqueswereusedtoconnec

2、tvariousdeformitiesofthemaxillain15adultpatients. In1927,MartinWassmundintroducedasurgicalprocedureformovingtheentireinaxilla.Theoperation,whichhassincebeencalledLeForteIosteotomyortotalmaxillaryosteotomy,wasfirstusedtocorrectananterioropenbite.Themaxillawasnotcompletelysectionedfromitsbonyattachme

3、nts,andnoattemptwasmadetomobilizethemaxillaatthetimeofsurgery.Postopcrativcly,incrmaillaryelastictractionwasusedtoclosetheopenbiteandstabilizethemaxilla.Inviewofthestateofartofanesthesiaatthetime,thelackofantibioticsandchemotherapeutics,andtheempiricalbasisformaxillarysurgery,thiswastrulyaremarkable

4、feat.Wassmund'sdirectapproachtothemaxillarydeformitywasclearlyyearsaheadofitstime. Thedesignofthebonyandsofttissueincisionshavebeencontinuallymodifiedtofacilitatemovementofthemaxillaandtomaintaincirculationtothemaxillaryboneandteeth.SchuchardtandKoledevisedatwo-stageproceduretopreventimpairmentofth

5、evascularsupplytothemaxilla.Postopcrativcly,Schuchardtusedweightsfromanoverheadtractiondevicetorepositionthemaxillaforward.Thesecondstageofhistechniqueinvolvedseparationofthepterygoidprocessesfromthemaxillarytuberosities.Despitesuchmeasures,hebecamedisenchantedwith(heprocedureandconcludedthattheoper

6、ationshouldnotbeusedtotreatpatientswithclefts.Axhausenusedelastictractionaftersurgerytofacilitateanteriormovementandretentionofatraumaticallyrelrodisplacedmaxilla.Inanapparentattempttocircumventtheseshortcomings,GilliesandConverseandShapiroadvocatedadvancingthemaxillabymeansofatransversepalatalcutof

7、the3unctionofthepalatineandmaxillarybone.Thesuccessofthisapproachwasnotcommentedon.Bonegraftinghasbeenadocatedtopromotebonyregenerationbetweenthebuccalbonecutsinthelateralportionsoftheinaxilla.Obwcgcscrmaintainedthatgraftingthespacebetweentheposteriormaxillaandthepterygoidplateswasessentialforstabil

8、ity. Inabilitytomovethemaxillathedesiredamountandrelapsewascommonfortheinnovatorsofthisoperation.Thesurgeon'sfearthatmobilizationofthemaxillawoulddevascularizeanddevitalizetheboneandteethwasthedominantreasonforsuchproblems.Thefearoftraumatizingvascularstructures,suchasthegreaterpalatineandinternalm

9、axillaryarteries,wasalsoamajorobjectiontothetechnique. Still,thebiologicbasisandsurgicalprinciplesformaxillaryosteotomiesremainedobscureandobviouslycontributedtopostoperativedevitalizationandlossofboneandteeth.Microangiographicandhistologicstudiesoftotalmaxillaryosteotomyperformedinadultrhesusmonke

10、ysshowedonlytransientvascularischemia.Minimalosteonecrosis,andearlyosseousunionwhenthemaxillawaspedicledessentiallyonlytothepalatalmucosa.Preservationofthehorizontalportionofthehardpalate.Pedicledtopalatalmucosaismovableandseparatedfromthenasalseptum.Theseproblemscanbeobviatedwhenthesurgeryisexecute

11、dfromthebuccalvestibulethroughthreeverticalincisionsandtheseptumandhorizontalpartofthepalatearemaintainedintact. Thesurgicaltreatmentplanmustbeflexible.Techniquesusingbothincisionshavebeenusedsuccessfullyandprovidethesurgeonmorelatitudeincorrectingmaxillarydeformitiesthanhasbeenpossiblewithprevious

12、lyreportedtechniques. ■Results Since1971,theLeForteI"downfracturing"Techniquehasbeenusedtoadvance,retract,raise,narrow,orexpandthemaxillain15patients(Table).Complexdcntofacialproblems(Fig5-7)suchasmaxillaryretrusion,skeletaltypeanterioropenbite,maxillaryasymmetry,bilateralbuccalorpalatalcrossbite,

13、maxillarydcnto-alvcolarprotrusion,andmaxillaryalveolarhyperplasiahavebeensuccessfullycorrected.Thesurgicalandorthodonticprinciplesusedintreating(hewdeformitiesareillustratedbythreecasereports(casenumberscorrespondwiththoseintheTable). CASEI-Figure5showshowmaxillaryretrusionassociatedwithmandibularp

14、rognathismina16year-oldboywasconectedbymaxillaryadvancement(surgicaltechniqueillustratedinFig1)andorthodontictreatment.Awideningofthealarbasesofthenoseandadecreaseofthenasolabialangleproducedapronouncedimprovementofthepatient*soverallfacialbalance(Fig5B,D,F,G).Interocclusalharmonywaslikewiseattained

15、(Fig5H-J). -Comment.Allobtusenasolabialangleisprobablythesinglemostimportantdiagnosticcriterionfortotalmaxillaryadvancement.Theupperlip-nosebalancecanbesignificantlyimprovedbyreductionofsuchanangle. Fig6-Case2.A,B,21-year-oldwomanwithshortupperlip,contour-deficientchin,narrownasalalarbeses,andla

16、ckofprominenceinmidfacialregionbeforetreatment(reposeposition).C,D:Improvedfacialbalance,wideningofnasalalarbases,andincreasedprominenceinzygomxaticomaxillaryandnasomaxillaryregionsaftermaxillarysurgery(techniqueshewninpartG).E:Preoperativecephalometrictracingshowinghighmandibularplane,7mmoverjet,an

17、dskeletal-typeClassIImalocclusionandunilateralpalatalcrossbite.G:Diagrammaticplanofmaxillarysurgery.Simultaneousanteriorandposteriormaxillaryosteotomiesinrepositionmaxillasuperiorlyandfacilitatemaxillomandibulararchalignment.H:Postoperativeocclusion.I:Compositecephalometrictracingsbefore(solidline-2

18、1year,3months)andthreemonthsaftersurgery(brokenline-21years,6months)showingautorotationofmandible,reductionofanteriorfacialheight,restorationofchincontour,improvedupperlipline-inciserrelationship,andfunctionaloverbiteandoverjet.Maxillaissuperimposedoveranteriorportionofmaxilla;mandibleissuperimprove

19、dovermandible.(Dr.CraigWilliams,residentinoralsurgery,ParktandMemorialHospital,Dallas,wasresponsiblefortheprimarycareofthispatient.) CASE2-A21-year-oldwomansoughttreatmenttodecreasethe"prominence"ofhermaxillaryteethandtoimprovethecontourofherface(Fig6A-B).Clinicalandcephalometricanalysesdisclosedah

20、ighmandibularplaneangle,totalmaxillaryalveolarhyperplasia,ahighpalatalvault,shortupperlip.contour-deficientchin,andlackofprominenceinthemidfacialregion(Fig6A,B,E).HerClassnmalocclusionwasassociatedwithaunilateralpalatalcrossbite,constrictedmaxillarycanines,anda7mmoveijet(Fig6F). Thesurgicaltechniqu

21、eshowninFigures24wasusedtorepositionthemaxiIliasuperiorly.Theanteriorportionoftheinaxillawasraised7mmandtheposteriorportionwasraised9mmtoimprovetheupperlip-incisorrelationship,tofacilitateautorotationofthemandible,andtocorrecttheoveijet(Fig6G).Verticalostectomiesweremadein(hesecondpremolarregionstof

22、acilitatecorrectionoftheunilateralcrossbiteandalignmentofthedentalarches.Bymovingtheposteriormaxillarydcnto-alvcolarsegmentsforward6mm,theextractionspaceswereclosedwithoutretractionoftheanteriorpartofthemaxilla.Theanteriormaxillarysegmentwassectionedbetweenthecentralincisorstoincreasetheintercaninew

23、idthandtoimprovethefirstpremolarrelationship.Facialharmonyandocclussalbalancewereattainedafterthreemonthsoftreatment(Fig6C,D,H,I).Arhinoplastyisplannedforthefuturetoreducethenasaldorsumandwidthofthealarbasesandtoraisethetipofthenose. -Comment.Inpatientswhodisplayanexcessiveamountofgingivaandteethin

24、apositionofreposeorwhensmiling,eitherbecauseofashortupperlipormaxillaryalveolarhyperplasia,orboth,(heentiremaxillaordenlo-alveolarportionofthemaxillacanberepositionedsuperiorlytoimprovetheupperliplinc-to-incisorrelationship.Theconsequentautorotationofthemandibleisaneffectivemeansofincreasingchinprom

25、inence.Tofacilitatesuperiormovementofthemaxilla,themaxillarybasalspineisreducedunderdirectvision.Theanteriornasalfloorcanbegroovedtoaccommodatethecartilaginousseptum.Submucosalresectionofthecartilaginousseptumortubinectomy,orboth,mayindeedbenecessarywhenthemaxillaissuperiorlyrepositionedinexcessof10

26、mm. CASE3-Figure7showshowmandibularprognathismassociatedwithretroniaxillismina21-year-oldwomanwascorrectedbymaxillaryadvancement,mandibularbodyostectomies,andorthodontics.Abroadnose,hypoplastic-appearingmidfacialregion,andprominentchinwerethedominantfacialfeaturesofthepatient(Fig7A-B).Cephalometric

27、studiesshowedretroinclinationofthemaxillaryandmandibularanteriorteeth(Fig7E).ExaminationofherocclusiondisclosedaClassmmolarrelationshipwithposteriorteethillcompletecrossbite.Themaxillarylateralincisors,secondandthirdmolars,andmandibularfirstmolarswerecongenitallymissing.Theloweranteriordentitionwasp

28、ositionedapproximately12mmanteriortothemaxillarydentition.Therewere7mmspacesbetweentherightandleftmandibularfirstandsecondpremolars. Afterthemaxillaryandmandibularteethwerealignedandtherotationscorrectedwithedge-wiseorthodonticappliances,themaxillawasadvanced6inmandthemandiblewasretracted7mmsimulta

29、neously.Overallfacialbalance(Fig7C-D)wasachievedfivemonthslaterbyrhinoplasty(nasalsurgerywasperformedbyDr.JackP.Gunter,Dallas). Fig7-Case3.A,B,Preoperativeappearance(age,21years,1months).C,D,Appearanceaftertreatment.E,Cephalometrictracingbeforesurgery(age,21year,7months)showingmandibularprog

30、nathismassociatedwithmaxillaryrestrusion.F:Compositecephalemetrictracingbeforesurgery(age,21years,7months)andfourmonthsaftersurgery(age21year,11months).Maxillaissuperimposedovermaxilla;mandibleissuperimposedoveranteriorpotionetmandible.G:Surgicaltreatmentplan.SimultaneousmaxillaryadvancementbyLeFort

31、eIosteotomyandretractionofmandiblebybodyostectomies(maxillarysurgicaltechniqueillustratedinFigureI). Althoughthemaxillaandmandiblewerepositionedasplanned,thefinalalignmentofthearcheswascompromisedbylackofpatientcooperation(retentionapplianceswerenotwornasprescribedaftertheorthodonticapplianceswerer

32、emoved).Whenthepatientwasseenagaintenmonthsafterjawsurgery,theanteriorteethwereendto-end;theposteriorteethwereincrossbiteandslightopenbite.Coordinatedstudyofthebefore-and-aftercephalometricradiographsandstudymodelsshowedslightproclinationoflowerincisors,interdentalspacingofthemaxillaryandmandibularp

33、remolars,anda6-mmincreasein(hewidthofthemandibulardentalarchintheinterpremolarregion.Occlusalbalancewasachievedafterthemaxillawassurgicallyadvanced3mmandwidened5mmintheinterpremolarregion. ■Complications WoundHealing-Theincisionalwoundshealedwithoutdiscerniblevascularischemia,infection,ordehiscen

34、ce.Postoperativestudieshaveshownminimalbonelossilltheinterdentalosteotomysitesandnoperiodontalproblems. Stabilty-Significantocclusalandskeletalrelapsehasbeendiscernibleinonlyonepatientwhosemaxillawasadvancedwithouthonegrafting(case8,Tabic).Thispatientwithacleftlipandcleftpalatewasanimpressiveillust

35、rationoftheneedforbonegrafting.Itisbeyondlhescopeofthispapertodiscusssmallpositionalchangesofthesurgicallyrepositionedmaxiliasthatoccurredinsomepatientsafterfixationapplianceswereremoved.Clinically,however,suchchangesappearedminimal. Esthetica-Inapatientwithpreviouslyrepairedcleftlipandcleftpalate(

36、case4,Table),thenasalestheticswascompromisedbyobvioussplayingofthealarbaseofonesideofthenoseaftermaxillaryadvancement.Inanotherpatient,therewasbilateralsplayingofthealarbasesandbucklingofthecartilaginousnasalseptumafterthemaxillawasraised10mm(case13,Table).Inbothpatients,facialbalancewasachievedafte

37、rrhinoplasty.BecauseLeForteIosteotomyforanteriororsuperiorrepositioningofthemaxillawillprobablyalternasalestheticsfavorablyorunfavorably,toalesserorgreaterdegree,thepreoperativecoordinationoftreatmentisessential.Prospectivepatientsmustbeapprisedofthepossibleneedforrhinoplastyafterthemaxillaisadvance

38、dorraised.Althoughtheoperationhasnotyetbeenusedtolengthenthemidfacialregion,itisinterestingtospeculateontheresultsofsuchaprocedure.Onthebasisofourclinicalobservationstodate,thenasalandmolarregionsmightbeexpectedtodecreaseinprominence.Theuseofsuchproceduresinthetreatmentofpatientswithdeepbitesandlowm

39、andibularplaneanglesisafruitfulfieldibrfurtherclinicalresearchandfbrexperimentsinanimals;itisalsoanotherfertilemeetingplacefororthodontistsandoralsurgeons. ■Summary Withproperplanning,execution,andfollow-upcare,themaxillacanbesurgicallyrepositionedintoastablerelationshipwiththemandible.Completemob

40、ility,preservationofviabilitybyproperdesignofthebonyandsofttissueincisionsandadequatefixationduringthehealingphasearcessentialtoobtainthisobjective.Variablemaxillarydeformitiesin15adultswerecorrectedbyLeForteIosteotomytechniques.Thetechnicalproblemsinplanninganddesignforthenecessarybonyandsofttissue

41、incisionsarediscussedandillustratedbythreecasereports. VOCABULARY KJSisg^s 1. inviewoffacilitate 2. circulationpterygoidprocesses 3. maxillofacialtuberositiesbymeanof 4. relapsedevascularies 5. devitalizeobscure II.microangiographic12.rhesusmonkeys 13.ischemia 局部缺血 14.osteonecrosis 骨壞死

42、 15.pedicled 帶蒂 16greaterpalatinearteries 腭大動脈 17.collateralcirculation 側枝循環(huán) 18.anastomoses 吻合支 19.maxillazygomaticcrest 顫牙槽崎 20.infraorbitalforamens 眶下孔 21.piriformapertures 梨狀孔 22.visualization 可視性 23.pleryomaxillarysuture 翼上頜縫 24.reposition 復位 25.repositioning 復位 26.mallette

43、d 錘擊 27.transantrally 通過上頜竇 28.hamulus 小鉤 29.manipulation 操作 30.nopracticalconsequence 無實際意義 31.perpendicularprocessof(hepalatine 腭骨垂直板 32.nasogastrictube 鼻胃管 33.evacuation 排空 34.vomiting 嘔吐 35.transosseouswires 骨內結扎鋼絲 36.circumzygomaticsuspensionwires 環(huán)額弓懸吊鋼絲 37.corticocanccll

44、ous 皮髓質的 38.nasopharynx 鼻咽部 39.contour 外形 40.interruptedhorizontalmattresssutures 間斷水平褥式縫合 41.iug 夾板的金屬突起 42.nasopharyngealairways 鼻咽通氣道 43.deadspace 死腔 44.sprayed 噴霧 45.intermaxillaryelastics 間彈力牽引 46.levelingofthelowerarch 排齊下牙 integrityofthegreaterpalatinearterieswasnotessent

45、ialtomaintaincirculationtothemaxilla. FigI-IncisionsofsontimeandboneforcorrectionofmaxillaryretrusionbyLeForteIosteotomytechnique.A:Typicaldental,facialandskeletalcharacteristicsofmandibularprognathismassociatedwithmaxillaryretrusion.B,C:Horizontalincisionthroughmucoperiosteuminthebuccolabialaspe

46、ctofdepthofvestibule.Horizontalsupraapicalosteotomyoflabialmaxillaextendingfrompiriformrimposteriorlytopterygomaxillaryfissure.D:Separationofnasalseptumfromsuperiorpartofmaxillawithosteotome;posteriorlateralnasalwallsectionedwithosteotome.E:Separationofmaxillafrompterygoidplatewithcurvedosteotome;su

47、rgeon'sfingerispositionedbelowpalatalmucosatofeelosteotomeasittranssectsbone.F:Maxillain"downfractured"position.Mucoperiosteumhasbeendetachedandretractedawayfromentiresuperiorsurfaceofmaxillaandhorizontalplateofpalatinebone;Posteriormaxillaisseparatedfromthepterygoidplatesandperpendicularprocessofpa

48、latinebonewithosteotomeandbur.G:Repositionedmaxillafixedtothepiriformrimsandzygomaticbuttresseswithtransosseouswires. Thecollateralcirculationwithinthemaxillaanditsenvelopingsofttissueandthenumerousvascularanastomosesin(heanteriorandposteriorpartsof(hemaxillapermitmanyvariationsofthetotalmaxillaryo

49、steotomytechnique.Intraosseousandintrapulpalcirculationwasnotsignificantlyalteredby(hebuccalsubapicalosteotomieswhenbonecutsweremadeawayfromtheapicesofteethandmaximalattachmentofthemucoperiosteumonthepalatalandbuccolabialgingivaofthemobilizedmaxillawaspreserxed.Theseresultsgeneratedclinicalconfidenc

50、einperformingtotalmaxillaryosteotomies.Thecurrentsurgicaltechniquewasmodifiedaftertheseanalogousinvestigationsinanimalsandpreviouslyreportedclinicaltechniques. ■Anesthesia Theoperationisperformedinthehospitalwiththepatientundergeneralanesthesiadeliveredviathenasoendotrachealroute.Successfullyadmin

51、isteredhypotensiveanesthesiahasreducedbleedingandfacilitatedsurgicaldissection.Itisrarelynecessarytousetransfusions,althoughtwounitsofpackedcellsareroutinelyavailableforuseatthelimeofsurgeryiftheneedshouldarise.Reducedoperativeshocksanddecreasedpostoperativenausea,vomiting,andedemaisadditionaladvant

52、agesofhypotensiveanesthesia.Becausesubmucosaloozingisdecreased,postoperativewoundhealingmayalsobeenhanced.Despitethesesignificantadvantages,theuseofhypotensiveanesthesiaisjustifiedonlywhenitenablesthesurgeontocarryouttheoperationbetter(hanhecouldwithconventionalanesthetictechniques.Theadvantagestoth

53、epatientandsurgeonmustbeweighedagainsttheincreasedrisks.Thetechnicalskillandexperienceoftheanesthesiologistmustbeofahighorder. ■SurgicalTechnique (Fig1,A-G)Ahorizontalincisionismadethroughthebuccolabialmucoperiosteumabovethemucogingivaljunctionextendingfromone-secondmolarregiontotheother(FigI,B).T

54、heincisionisplacedinthebuccolabialaspectofthedepthofthevestibule,atabouttheleveloftheapicesoftheteeth.Themarginsofthesuperiorflapareraisedtoexposetheentirelateralwallsofthemaxillazygomaticcrests,infraorbitalforamens,andthepiriformapertures.Theinferiornwcoperioscealtissuesareminimallyelevatedsothat(h

55、eyprovideadditionalvascularsupplytothemaxillaryboneandteeth.Goodvisualizationoftheposterolateralportionofthemaxillaisessentialandisaccomplishedbypositioningthetipofacurvedcheekretractorathepterj'gomaxillarysuture(Fig1,B).Anothercheekretractorisplacedanteriorlytofacilitatevisualizationoftheanterolate

56、ralportionofthemaxilla.Directvisualizationandpalpationoftheboneencasingtheapicesoftheteethassessthelengthoftheteeth.Thesefindingsarecorrelatedwithnieasurenientstakenfrompanoramicorlateralcephalometricradiographyorboth.Sothatahorizontallinecanbeetchedinthebone3to5mmabove(heapicesoftheleeih. Horizont

57、alsupraapicalosteotomiesofthelateralportionsofthemaxiliasaremadefromthelateralpartofthepiriformrimposteriorlyacrossthecaninefossaandthroughthezygomaticmaxillarycresttothepterygomaxillaryfissureusingafissureburinastraighthandpieceorahighspeedreciprocatingsaw.Insomecases,dependingontheexistingfacialdc

58、fbrmify,greateraugmentationof(hemidfacialregionwillresultfromplacementoftheanteriorosteotomymoresuperiorly.Ideally,thesupraapicalbonecutsarcmade3to4mmormoreabovetheapicesofthemaxillaryteeth. Themucoperiosteumiselevatedfromtheanteriorfloorofthenose,nasalseptum,andlateralwallsofthenasalcavitytofacili

59、tateseparationofthemaxillafromthesestructures.Anasalseptalosteotomeispositionedabovetheanteriornasalspineparallelwiththehardpalateandmallcttcdtoseparatethenasalsepunifromthemaxilla(Fig1,D).Theanteriorlaternasalwallissectioned(ransantrallywithafissureburinastraighthandpiece.Theposteriorlateralnasalwa

60、llissectionedwithasharposteotomeabovethelevelofthenasalfloor.Inmanyinstances,however,thisboneismthinthatdoesnothavetobeosteotoinized.Finally,sharppterygoidosteotomeismalJettedintopterygomaxillarysuturetoseparatethemaxillaryfromthepterygoidplates(FigI,E).Digitalpressureonthepalatalmucosaintheregionth

61、ehamuluspermitsthesurgeontofeelosteotomeasittransectsthebonewithoutfrallmatizingtheunderlyingmucoperiosteum.Theosteotomeispositionedinferiorlytominimizedangertothevascularstructuresintheptetygomaxillaryfissure.Bymanipulationofthecurvedosteotomeandmanualpressureagainstthetuberosities,themaxillaismade

62、partiallymobile. Atthispoint,downwardmovementfracturesthemaxilla.Graduallyincreasingintopressureontheanteriorportionsofthemaxillafacilitatesvisualizationofthesuperiorsurfaceofthemaxillaandlateralnasalwalls(Fig1,F).Theniucoperiosteumiselevatedandretractedawayfromtheentiresuperiorsurfaceofthemaxilla,

63、horizontalplateofthepalatinebone,andlateralnasalwalls.Transectionofthegreaterpalatinevesselsisofnopracticalconsequence.Digitalpressuregraduallycompletesfracturingoftheinaxilla,withouttheuseofdisimpactionforceps.Thedownwardpositionofthemaxillaprovidesexcellentaccessforcompletelyseparatingthemaxillafr

64、om(hepterygoidplatesandperpendicularprocessofthepalatinebone(Fig1,F).Thiscanbeaccomplishedwithaburoranosteotome.Bycarefulmanipulationoftheosteotomeandforwardpressureagainstthetuberositiesandlowerpartofthemaxilla,themaxillaismadecompletelymobileandmovedintotheplannedposition.Themaxillamustbemadesomob

65、ilethatitcanbemovedwithonlylightdigitalpressureintothedesiredrelationshiptothemandible.Usingapreviouslypreparedinterocclusalsplintasanindex,themaxillaisimmobilized.forsixtoeightweekswithstainlesssteelwiresligatedbetweenpreviouslyplacedarchbarsororthodonticarchwires.Beforeplacingtheintermaxillaryfixa

66、tion,anasogastrictubeisplacedinthenasalpassageoppositethesideofthenosethathasbeenintubatedinfacilitateevacuationofbloodfromthestomachand(opreventvomitingintheearlypostoperativeperiod.Thetube,whichisperiodicallyirriogated,isusuallyremovedwithin24hourswhentheaspirantofintermittentsuctionisclear. Themobilizedmaxillaisfixeddirectlytothepiriformrimsandzygomaticbuttresseswithtransosseouswireswheneverfeasible.When,however,theboneintheseareasistoothintosupportinterosseouswires,theuseofinfraorbifalrimor