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1、UnitTwenty COMPLICATIONSOFEXODONTICS Complicationsarisefromerrorsinjudgment,misuseofinstruments,exertionofextremeforce,andfailuretoobtainpropervisualizationpriortoacting.Theoldadage"todogood,youmustseegood"isapropostoexodontics,andonemightadd"Dowellwhatyousee." Becauseoftheanatomyofthemaxillaryan

2、trumanditsproximitytothemaxillarypremolarandmolarroots,theantrumshouldalwaysbeconsideredwhenextractingteethinthisarea. Extremeforceappliedtouppermolarscanresultinremovalofthemolartoothalongwiththeentiremaxillaryalveolarprocessandtheflooroftheantrum.Thefirst,second,andthirdmolars,alongwiththetuberos

3、ity,havebeenremovedinonesegmentbecauseofimproperuseofforceinthemaxilla.Ifduringanextractionthesurgeonfeelslargesegmentsofbonemovingwiththetoothwhenpressureisapplied,theforcepsshouldbesetasideandaflapraised.Ifjudiciousremovalofpartofthealveolarboneallowsthetoothtoberemoved,thentheremainingbone,whichi

4、sattachedtoperiosteum,mayheretained,anditwillheal.Thiswillminimizethebonydefect.Ifthebonecannotberemovedfromthetooth,themucosashouldbeincisedandreflectedsothatthemucosawillnottearasthetoothandboneareremoved.Alacerationismuchmoredifficulttorepairthanawell-plannedincision. Largeantralperforationsresu

5、ltingfromexodonticsshouldbeclosedatthetimeoftheextraction.Theboneintheareashouldbesmoothedwitharongeurorbonefile.Theniucoperiostealflapisreturnedtoposition,andawatertightclosureshouldbeaccomplishedwithoutputtingunduepressureontheflap.Ifthiscannotbedone,theflapshouldbefreedbymeansofanincisionextendin

6、gverticallyintothemucobuccalfoldandthemucosaoftheflapunderminedtoallowittoadvanceoverthedefect. Whentheantrumisenteredduringexodontics,thepatientshouldbemadeawareof(hesituationandaskedtonotblowthenosepostopcrativelyandalsotorefrainifpossiblefromcoughingorsneezing.Antibioticsandvasoconstrictivenosed

7、ropsareprescribedtoguardagainstinfectionofthesinusandtoallowforemptyingofthefluidthatwillcollectwithinthesinus. Occasionally,buccalrootsofpremolarsandmolarsarcpushedlaterallythroughthewallofthemaxillaandlieabovetheattachmentofthebuccinatormuscle.Whenlheoperatorusesrootcxolcvcrsinthisarea,afingeroft

8、helefthandshouldbeheldagainstthebuccalplatesothatheorshecanbeawareofanymovementoflherootinthisdirection.Iftherootisdislodgedintothesetissues,asmallincisionismadeinthemucosainferiortotheroottipandtheroottipisremovedwithasmallhemostatorsimilarinstrument. Theinfratemporalspaceliesdirectlyposteriorands

9、uperiortothetuberosityofthemaxilla.Withinthisspaceliemanyimportantneurovascularstructures.Intheelevationofthirdmolarsorthirdmolarroottipsandintheremovalofsupernumerarymolars,caremustbetakennottodislodgethemposteriorly.Ifanobjectistoberemovedfromtheinfratemporalspace,adequatevisualizationandcarefuldi

10、ssectionarenecessary.Theincisionshouldincludetheentiretuberosityandextendposteriorlytotheanteriorpillarofthefauces.Blinddissectionandgropingforobjectsinthisareacanbecomplicatedbymassivehemorhageornervedamage. Inthethirdmolarregionofthemandible,thelingualsurfaceofthemandiblecurveslaterally,closetoth

11、eapicesofthistooth.Thereforeitisnotdifficulttodislodgearoottipinferiorlyintothisspacewhenthelingualplateisfractured.Whenaroottipisdisplacedinthisarea,afingershouldbeplacedinferiortotheroottip(inthemouth)tostabilizethetipagainstthelingualplateofthemandible.Accesslo(hisareaisgainedbymakingamucoperiosl

12、ealflaponthelingualsideofthemandibleandextendinganteriorlyenoughthatthetissuescanberetractedlinguallyforgoodvision. Recoveryofaroottipinthemandibularcanalisprincipallyaproblemofaccessandvision.Usuallyitisdifficulttoremoveboneoverlyingthecanalfromwithinthedepthsofthewound,whichisusuallythethirdmolar

13、socket.Accessmaybegainedbyremovalofbonefromthebuccalplateandbycarefulremovalofbonethatoverliesthecanal.Ifoneofthevascularcomponentsofthecanalhasbeeninjured,itmaybenecessarylopackthesocketwithgauze,allowing10minutesforcontrolofthehemorrhage.Ifhemorrhagecannotbecontrolledinthismanner,theinjuredvessels

14、houldbeseveredcompletelyandallowedtoretractintothecanal.Atthistimethesocketisagainpacked,andhemorrhagecontrolisusuallyaccomplished. POSTEXODONTICCOMPLICATIONS Postoperativehemorrhageisthemostcommoncomplicationafterexodontics.If(hepatientcallsfromhometoreportthathemorrhagehasstartedagain,heshouldbe

15、advisedfirsttoclearthemouthofanybloodclotswithagauzespongeandthenrinsethemouthwithwarmsaltwater.Allexcessivebloodclotsshouldberemovedfromthevicinityofthesocket,buttheclotinthesocketshouldnotberemoved.Thepatientisinstructedtobitefirmlyonasterilegauzespongethathasbeenfoldedsothatpressureisexertedonthe

16、areaofsurgery.Ifasterilegauzespongeisnotavailable,thepatientmayuseateabagthathasbeenplacedincoldwatertosoftenthetealeaves.Thepatientisadvised(obite(notchew)onthepadorteabagfor20minutes.Ifbleedingpersistsattheendofthisperiod,thepatientshouldbeseenbythedentist. Incasesofpersistenthemorrhage,gauzespon

17、gesandhemostaticagentssuchasGelfoam,topicalthrombin,oxidizedcellulose,andAvitenemaybehelpfulforthelocalcontrolofhemorrhageinadditiontoanadequatearmamentarium. Thepatientisseatedandalocalanestheticadministered.Theclotthathasformedwithinthesocketisremoved.Next,theareaofhemorrhageislocated.Ifthehemorr

18、hageiscomingfromabonebleederwithinthesocket,thedullsideofacuretisusedloburnishtheboneintheareaofhemorrhage.Ifgeneralizedbonebleedingispresent,thesocketispackedwithahemostaticagentsuchasGelfoamsoakedinthrombin,andapurse-siringsutureisapplied(oholdthehemostaticagentinplace.Thepatientisaskedtobiteonamo

19、istgauzesponge.Ifthehemorrhageisfromthesurroundingsofttissue,atensionsutureisplacedtoapplypressuretothearea. Inpatientswithadvancedperiodontaldisease,postoperativebleedingwilloccurifgranulationtissueisallowedtoremainafterremovaloftheaffectedteeth.Atthetimeofsurgeryafewminutesspentremovingthegranula

20、tiontissueandsuturingthealveolarmucosawillassuregoodhemorrhagecontrol. Infectioncanoccurasapostoperativecomplication.TreatmentofsuchinfectionismanagedbyusingtheprinciplesoutlinedinChapter10. Drysocket(localizedosteitis)isoneofthemostperplexingpostoperativecomplications.Theetiologyofthedrysocketisu

21、nknown,butthefollowingfactorsincreasetheincidenceofthispainfulpostextractionsequela:trauma,infection,decreasedvascularsupplyofthesurroundingbone,andgeneralsystemiccondition. Theconditionrarelyoccurswhenminimaltraumaticmethodsarcemployedduringdifficultorsimpleextractions.Meticulousdebridementofallex

22、tractionwoundsshouldbedoneroutinely. Theetiologymayberelatedtofactorsthatimpedeorpreventadequatenourishmentfromreachingthenewlyformedbloodclotwithinthealveolus.Patientswithdenseosteoscleroticboneorwithteeththathaveosteoscleroticalveolarwallsbecauseofchronicinfectionarepredisposedtodrysockets. Drys

23、ocketmostcommonlydevelopsonthethirdorfourthpostoperativedayandischaracterizedbysevere,continuouspainandnecroticodor.Clinicallytheconditionmaybedescribedasanalveolusinwhichtheprimarybloodclothasbecomenecroticandremainswithinthealveolusasasepticforeignbodyuntilitisremovedbyirrigation.Thisusuallyoccurs

24、afewdaysafterextraction,leavingthealveolarwallsdivestedoftheirprotectivecovering.Severepain,whichcanbecontrolledonlybylocalapplicationofpotentanalgesicsandoralorparenteraluseofanalgesicsornarcoticsaccompanythedenudedbone. Totreatasepticalveolusproperly,onemustunderstandthephysiologyofbonerepair.Ift

25、helossoftheprimarybloodclotresultsfromascleroticconditionofthealveolarwallsandtheabsenceofnutrientvessels,thentheresultingdenudedbonesurfacemustbeviewedasanyotherdenudedbonesurface,andthedentistmustrelyonnature'smethodsofbonerepairforultimaterecoveryandnotemployanyothermethodsthatwoulddisturbtheheal

26、ingprocess. Asepticalveolusisadenudedbonesurface.Natureabhorsdenudedboneandrespondstorepairit.Behindthisdenudedandtraumatizedsurfaceanimmediatemechanismissetuptophysiologicallycorrectthedefect.Alldenudedbonebecomesnecroticandmustberemovedbeforeitcanbereplacedbynormalbone.Duringthisperiodthecontiguo

27、usregionbehindthealveolusisdefendedagainstinvasionofpyogenicorganismswithinthesepticalveolus,providednothingisdonetobreakthroughorviolatethiswalluntiltherepairmechanismisreadytoreplacethenonvitalstructure.Thisprocessusuallylakes2(o3weeks,dependingon(heregenerativecapacityoftheindividual. Withthecom

28、pletionofthiscyclethenonvitalalveolarwallissequestratedmolecularlyorenmasseandimmediatelybehinditisadefensiveandregenerativelayerofjuvenileconnectivetissuethatultimatelyfillsthevoidandundergoesosseousreplacement.Duringthisperiod,treatmentshouldbedirectedonlytomaintenanceofwoundhygiene,withemployment

29、ofantiseptic,analgesicdressingswithinthealveolusofsufficientpotencytokeepthepatientcomfortable.Naturemustdo(herepairing.Curettageiscontraindicatedandwillnotonlydelayphysiologicalhealingandrepairbutmayalsopermitinvasionofinfectionintoandbeyondtheareaofdefenseimmediatelybehindthedenudedalveolus. Prev

30、ention,ofcoarse,isthebesttreatmenttothisend.atraumaticsurgery,avoidanceofcontamination,andmaintenanceofagoodlevelofgeneralhealthisimportant. Whenadrysocketdoesdevelop,treatmentshouldbepalliative.Thesocketisgentlyirrigatedwithwarmnormalsalinesolutiontoremovealldebris.Afterthesockethasbeencarefullydr

31、ied,itislightlydressedwith1/4-inchplaingauzesaturatedwithanobtundentpaste,suchasequalpartsofthymoliodidepowderandbenzocainecrystalsdissolvedineugenol.Thedressingmaybechangedasnecessaryuntilpainhassubsidedandgranulationtissuehascoveredthewalkofthesocket. VOCABULARY 1.exodontics 拔牙學(xué) 2.adage 諺語，格

32、言 3.heaproposto 對(duì)……是恰當(dāng)?shù)? 4.maxillaryantrum 上頜竇 5.proximityto 鄰近 6.extractingteeth 拔牙 7.alveolarprocess 牙槽突 8.tuberosity （上頜）結(jié)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.und

33、ermine 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.hemostat 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.pill

34、arofthefauces 咽門柱 28.dissectionandgroping 剝離和摸索 29.stabilize 穩(wěn)定 30.accessto 開口，進(jìn)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.gelfoam 明膠海綿 37.topicalthrombin 局部凝血酶 38.oxidizedcellulose 氧化纖維素 39.armamentarium 裝備 40.cure

35、t 刮匙 41.purse-stringsuture 荷包縫合 42.granulationtissue 肉芽組織 43.drysocket(osteitis) 干槽癥 44.perplexing 復(fù)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(xì)菌分離成分子狀 憎惡年輕的姑息療法 bepredisposedto 49. necroticodordivest 50. denudedbonepotentanalgesics 51. narcoticspyogenicorganisms 52. sequestratemolecularly 53. abhorjuvenile 54. palliative