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1、UnitTwentyCOMPLICATIONSOFEXODONTICSComplicationsarisefromerrorsinjudgment,misuseofinstruments,exertionofextremeforce,andfailuretoobtainpropervisualizationpriortoacting.Theoldadagetodogood,youmustseegoodisapropostoexodontics,andonemightaddDowellwhatyousee.Becauseoftheanatomyofthemaxillaryantrumandits

2、proximitytothemaxillarypremolarandmolarroots,theantrumshouldalwaysbeconsideredwhenextractingteethinthisarea.Extremeforceappliedtouppermolarscanresultinremovalofthemolartoothalongwiththeentiremaxillaryalveolarprocessandtheflooroftheantrum.Thefirst,second,andthirdmolars,alongwiththetuberosity,havebeen

3、removedinonesegmentbecauseofimproperuseofforceinthemaxilla.Ifduringanextractionthesurgeonfeelslargesegmentsofbonemovingwiththetoothwhenpressureisapplied,theforcepsshouldbesetasideandaflapraised.Ifjudiciousremovalofpartofthealveolarboneallowsthetoothtoberemoved,thentheremainingbone,whichisattachedtop

4、eriosteum,mayheretained,anditwillheal.Thiswillminimizethebonydefect.Ifthebonecannotberemovedfromthetooth,themucosashouldbeincisedandreflectedsothatthemucosawillnottearasthetoothandboneareremoved.Alacerationismuchmoredifficulttorepairthanawell-plannedincision.Largeantralperforationsresultingfromexodo

5、nticsshouldbeclosedatthetimeoftheextraction.Theboneintheareashouldbesmoothedwitharongeurorbonefile.Theniucoperiostealflapisreturnedtoposition,andawatertightclosureshouldbeaccomplishedwithoutputtingunduepressureontheflap.Ifthiscannotbedone,theflapshouldbefreedbymeansofanincisionextendingverticallyint

6、othemucobuccalfoldandthemucosaoftheflapunderminedtoallowittoadvanceoverthedefect.Whentheantrumisenteredduringexodontics,thepatientshouldbemadeawareof(hesituationandaskedtonotblowthenosepostopcrativelyandalsotorefrainifpossiblefromcoughingorsneezing.Antibioticsandvasoconstrictivenosedropsareprescribe

7、dtoguardagainstinfectionofthesinusandtoallowforemptyingofthefluidthatwillcollectwithinthesinus.Occasionally,buccalrootsofpremolarsandmolarsarcpushedlaterallythroughthewallofthemaxillaandlieabovetheattachmentofthebuccinatormuscle.Whenlheoperatorusesrootcxolcvcrsinthisarea,afingerofthelefthandshouldbe

8、heldagainstthebuccalplatesothatheorshecanbeawareofanymovementoflherootinthisdirection.Iftherootisdislodgedintothesetissues,asmallincisionismadeinthemucosainferiortotheroottipandtheroottipisremovedwithasmallhemostatorsimilarinstrument.Theinfratemporalspaceliesdirectlyposteriorandsuperiortothetuberosi

9、tyofthemaxilla.Withinthisspaceliemanyimportantneurovascularstructures.Intheelevationofthirdmolarsorthirdmolarroottipsandintheremovalofsupernumerarymolars,caremustbetakennottodislodgethemposteriorly.Ifanobjectistoberemovedfromtheinfratemporalspace,adequatevisualizationandcarefuldissectionarenecessary

10、.Theincisionshouldincludetheentiretuberosityandextendposteriorlytotheanteriorpillarofthefauces.Blinddissectionandgropingforobjectsinthisareacanbecomplicatedbymassivehemorhageornervedamage.Inthethirdmolarregionofthemandible,thelingualsurfaceofthemandiblecurveslaterally,closetotheapicesofthistooth.The

11、reforeitisnotdifficulttodislodgearoottipinferiorlyintothisspacewhenthelingualplateisfractured.Whenaroottipisdisplacedinthisarea,afingershouldbeplacedinferiortotheroottip(inthemouth)tostabilizethetipagainstthelingualplateofthemandible.Accesslo(hisareaisgainedbymakingamucoperioslealflaponthelingualsid

12、eofthemandibleandextendinganteriorlyenoughthatthetissuescanberetractedlinguallyforgoodvision.Recoveryofaroottipinthemandibularcanalisprincipallyaproblemofaccessandvision.Usuallyitisdifficulttoremoveboneoverlyingthecanalfromwithinthedepthsofthewound,whichisusuallythethirdmolarsocket.Accessmaybegained

13、byremovalofbonefromthebuccalplateandbycarefulremovalofbonethatoverliesthecanal.Ifoneofthevascularcomponentsofthecanalhasbeeninjured,itmaybenecessarylopackthesocketwithgauze,allowing10minutesforcontrolofthehemorrhage.Ifhemorrhagecannotbecontrolledinthismanner,theinjuredvesselshouldbeseveredcompletely

14、andallowedtoretractintothecanal.Atthistimethesocketisagainpacked,andhemorrhagecontrolisusuallyaccomplished.POSTEXODONTICCOMPLICATIONSPostoperativehemorrhageisthemostcommoncomplicationafterexodontics.If(hepatientcallsfromhometoreportthathemorrhagehasstartedagain,heshouldbeadvisedfirsttoclearthemoutho

15、fanybloodclotswithagauzespongeandthenrinsethemouthwithwarmsaltwater.Allexcessivebloodclotsshouldberemovedfromthevicinityofthesocket,buttheclotinthesocketshouldnotberemoved.Thepatientisinstructedtobitefirmlyonasterilegauzespongethathasbeenfoldedsothatpressureisexertedontheareaofsurgery.Ifasterilegauz

16、espongeisnotavailable,thepatientmayuseateabagthathasbeenplacedincoldwatertosoftenthetealeaves.Thepatientisadvised(obite(notchew)onthepadorteabagfor20minutes.Ifbleedingpersistsattheendofthisperiod,thepatientshouldbeseenbythedentist.Incasesofpersistenthemorrhage,gauzespongesandhemostaticagentssuchasGe

17、lfoam,topicalthrombin,oxidizedcellulose,andAvitenemaybehelpfulforthelocalcontrolofhemorrhageinadditiontoanadequatearmamentarium.Thepatientisseatedandalocalanestheticadministered.Theclotthathasformedwithinthesocketisremoved.Next,theareaofhemorrhageislocated.Ifthehemorrhageiscomingfromabonebleederwith

18、inthesocket,thedullsideofacuretisusedloburnishtheboneintheareaofhemorrhage.Ifgeneralizedbonebleedingispresent,thesocketispackedwithahemostaticagentsuchasGelfoamsoakedinthrombin,andapurse-siringsutureisapplied(oholdthehemostaticagentinplace.Thepatientisaskedtobiteonamoistgauzesponge.Ifthehemorrhageis

19、fromthesurroundingsofttissue,atensionsutureisplacedtoapplypressuretothearea.Inpatientswithadvancedperiodontaldisease,postoperativebleedingwilloccurifgranulationtissueisallowedtoremainafterremovaloftheaffectedteeth.Atthetimeofsurgeryafewminutesspentremovingthegranulationtissueandsuturingthealveolarmu

20、cosawillassuregoodhemorrhagecontrol.Infectioncanoccurasapostoperativecomplication.TreatmentofsuchinfectionismanagedbyusingtheprinciplesoutlinedinChapter10.Drysocket(localizedosteitis)isoneofthemostperplexingpostoperativecomplications.Theetiologyofthedrysocketisunknown,butthefollowingfactorsincreaset

21、heincidenceofthispainfulpostextractionsequela:trauma,infection,decreasedvascularsupplyofthesurroundingbone,andgeneralsystemiccondition.Theconditionrarelyoccurswhenminimaltraumaticmethodsarcemployedduringdifficultorsimpleextractions.Meticulousdebridementofallextractionwoundsshouldbedoneroutinely.Thee

22、tiologymayberelatedtofactorsthatimpedeorpreventadequatenourishmentfromreachingthenewlyformedbloodclotwithinthealveolus.Patientswithdenseosteoscleroticboneorwithteeththathaveosteoscleroticalveolarwallsbecauseofchronicinfectionarepredisposedtodrysockets.Drysocketmostcommonlydevelopsonthethirdorfourthp

23、ostoperativedayandischaracterizedbysevere,continuouspainandnecroticodor.Clinicallytheconditionmaybedescribedasanalveolusinwhichtheprimarybloodclothasbecomenecroticandremainswithinthealveolusasasepticforeignbodyuntilitisremovedbyirrigation.Thisusuallyoccursafewdaysafterextraction,leavingthealveolarwa

24、llsdivestedoftheirprotectivecovering.Severepain,whichcanbecontrolledonlybylocalapplicationofpotentanalgesicsandoralorparenteraluseofanalgesicsornarcoticsaccompanythedenudedbone.Totreatasepticalveolusproperly,onemustunderstandthephysiologyofbonerepair.Ifthelossoftheprimarybloodclotresultsfromasclerot

25、icconditionofthealveolarwallsandtheabsenceofnutrientvessels,thentheresultingdenudedbonesurfacemustbeviewedasanyotherdenudedbonesurface,andthedentistmustrelyonnaturesmethodsofbonerepairforultimaterecoveryandnotemployanyothermethodsthatwoulddisturbthehealingprocess.Asepticalveolusisadenudedbonesurface

26、.Natureabhorsdenudedboneandrespondstorepairit.Behindthisdenudedandtraumatizedsurfaceanimmediatemechanismissetuptophysiologicallycorrectthedefect.Alldenudedbonebecomesnecroticandmustberemovedbeforeitcanbereplacedbynormalbone.Duringthisperiodthecontiguousregionbehindthealveolusisdefendedagainstinvasio

27、nofpyogenicorganismswithinthesepticalveolus,providednothingisdonetobreakthroughorviolatethiswalluntiltherepairmechanismisreadytoreplacethenonvitalstructure.Thisprocessusuallylakes2(o3weeks,dependingon(heregenerativecapacityoftheindividual.Withthecompletionofthiscyclethenonvitalalveolarwallissequestr

28、atedmolecularlyorenmasseandimmediatelybehinditisadefensiveandregenerativelayerofjuvenileconnectivetissuethatultimatelyfillsthevoidandundergoesosseousreplacement.Duringthisperiod,treatmentshouldbedirectedonlytomaintenanceofwoundhygiene,withemploymentofantiseptic,analgesicdressingswithinthealveolusofs

29、ufficientpotencytokeepthepatientcomfortable.Naturemustdo(herepairing.Curettageiscontraindicatedandwillnotonlydelayphysiologicalhealingandrepairbutmayalsopermitinvasionofinfectionintoandbeyondtheareaofdefenseimmediatelybehindthedenudedalveolus.Prevention,ofcoarse,isthebesttreatmenttothisend.atraumati

30、csurgery,avoidanceofcontamination,andmaintenanceofagoodlevelofgeneralhealthisimportant.Whenadrysocketdoesdevelop,treatmentshouldbepalliative.Thesocketisgentlyirrigatedwithwarmnormalsalinesolutiontoremovealldebris.Afterthesockethasbeencarefullydried,itislightlydressedwith1/4-inchplaingauzesaturatedwi

31、thanobtundentpaste,suchasequalpartsofthymoliodidepowderandbenzocainecrystalsdissolvedineugenol.Thedressingmaybechangedasnecessaryuntilpainhassubsidedandgranulationtissuehascoveredthewalkofthesocket.VOCABULARY1.exodontics拔牙學2.adage諺語，格言3.heaproposto對是恰當?shù)?.maxillaryantrum上頜竇5.proximityto鄰近6.extracting

32、teeth拔牙7.alveolarprocess牙槽突8.tuberosity（上頜）結節(jié)9.judiciousremoval審慎地除去10.mucosa粘膜11.antralperforation上頜竇穿孔12.rongeurorbonefile骨鉗或骨挫13.mucoperiostealflap骨粘膜瓣14.mucobuccalfold頰粘膜皺囊15.undermine潛掘16.refrainfrom制止17.antibiotics抗生素18.vasoconstrictive血管收縮的19.buccinatormuscle頰肌20.exolevers牙挺21.dislodge逐出22.he

33、mostat止血鉗23.infratemporalspace額下間隙24.inferiorto(superiorto)在下方（上方25.posteriorly(anteriorly)在后部（在前部）26.supernumerarymolar多生的磨牙27.pillarofthefauces咽門柱28.dissectionandgroping剝離和摸索29.stabilize穩(wěn)定30.accessto開口，進路31.retract拉開，翻轉(zhuǎn)32.sever切斷33.pack填塞34.excessivebloodclot過量的血塊35.sterilegauzesponge無菌海綿紗布36.gelf

34、oam明膠海綿37.topicalthrombin局部凝血酶38.oxidizedcellulose氧化纖維素39.armamentarium裝備40.curet刮匙41.purse-stringsuture荷包縫合42.granulationtissue肉芽組織43.drysocket(osteitis)干槽癥44.perplexing復雜的45.sequela繼發(fā)癥46.meticulousdebridement小心的清創(chuàng)47.impede阻礙48.osteosclerotic骨硬化的易患壞死氣味剝光裸露的骨有力的止痛藥麻醉劑化膿性細菌分離成分子狀憎惡年輕的姑息療法bepredisposedto49. necroticodordivest50. denudedbonepotentanalgesics51. narcoticspyogenicorganisms52. sequestratemolecularly53. abhorjuvenile54. palliative