Scr.1 - Removable Partial Dentures

Download Scr.1 - Removable Partial Dentures

Post on 04-Apr-2018

214 views

Category:

Documents

0 download

Embed Size (px)

TRANSCRIPT

  • 7/29/2019 Scr.1 - Removable Partial Dentures

    1/8

    Remavable artial denture

    Hebah ra3d ramadneh

    3essam el-3alam

    1

    20

  • 7/29/2019 Scr.1 - Removable Partial Dentures

    2/8

    1

    Removable Partial DenturesInthissemesterwewilltalkaboutremovablepartialdenture,whichis moredifficultthancompletedenturebecauseitssmallerandneedotherstepstobe

    done. isaprosthesisthatreplacesoneormoremissingteeth.(not

    allteeth)

    Inpartialprosthodonticswehave2types:1-interimprosthodontics(Interim (transitional)) :( , , )***Itsalmost(notalways)madebyacrylic(looklikecompletedenture),ithasclasps .

    2-diffinitiveprosthodontics(permanent):thefinalone

    ***ithasmetalframeworkitsusuallymadeofcobaltchromiumwhichisverystrongmaterial(notcorrodeeasily)&itsbiocompatibleforthetissueinthemouth.

    wecanalsousenickelchromium itsastrongmaterial,butitsstillhasproblemwiththetissueinthemouth,5%ofpeoplehasnickelsensitivityso,wetrynottousenickelindentistry.

  • 7/29/2019 Scr.1 - Removable Partial Dentures

    3/8

    2

    NOTE:_weusechromiumtoprotectthecobaltmaterialbecausechromiumisfastertoreactwithoxygen._Inthelabwewillmakemetalframeworkdenture.Intheclinicyouwillmeetdifferentcaseswithdiferentmissingteethso,itsdifficulttodescribeeachcasetothetechnicianssowehavedifferentclassificationsystemsweredesigned,andtheseweredoneinNorthAmerica .Theclassificationsystemthatyouhavealreadybeenfamiliarwithis

    with .DrKennedyproposedthisclassification90yearsago,Kennedysclassificationhassomedeficienciesand

    thatswhyMr.Applegatecamealongandmadesomemodifications. Wehavedifferentclassesinkennedysclassification:

    *class-I:themostmissingteeth,theanteriorteethispresentbuttheposteriorteethislost.wecandescribeitasbilateraldisextension( Bilateral edentulous).itcanbeupperorlowerbutinbothside(bothsidemissing).

    *class-II:insteadofhavingmissingteethinbothside,wehavemissingteethinoneside,itsunilateraldisextension, Unilateral edentulous(onesidemissing).

  • 7/29/2019 Scr.1 - Removable Partial Dentures

    4/8

    3

    *class-III:wehavespacedmissingteeth,thatmeanmissingteethintheanteriorandposteriorpartofthemouthwecalleditboundspaced( ).itsaUnilateralareaboundedbyanterior&posteriornaturalteeth.

    *class-IV:itsjustlikeclass-IIIbutitsspecial,itbilateralcrossthemidline.

  • 7/29/2019 Scr.1 - Removable Partial Dentures

    5/8

    4

    Applegatesmodifications:thefirstoneisspacemodification:

    youhaveadditionalspace,ithasnothingtodowiththenumberofmissingteeth,itdealwiththenumberofmissingspace.EXs:-ifyouhavepatientwithkennedysclass-Iandhemisshiscentralincisoryou

    calleditkennedysclass-Imodification-1 .ifthispatientalsolosthislateralincisorinthesamesidewealsocalleditkennedysclass-Imodification-becauseitsdealwithnumberofspacesnotthenumberofthemissingteeth.- ifyouhavepatientwithkennedysclass-IandhemisshiscanineandlateralincisorintheRtandintheLf,wecalleditkennedysclass-Imodification-1-2

    ***WECOUNTTHESPACESNOTTHEMISSINGTEETH***

    -NOTE:Thereis modificationspacein ).OnlyClassI,II,IIhasmodificationspace.becauseI take the most posterior edentulous area and the anterior spacebecomes a modification.

    In Ihave edentulousspace,thereisamistakeintheslidesitsnotbilateralitsjustunilateral(oneedentulousarea,itcanbe2butithas

    differentname),nowifthisspacecrossesthemidlineitbecomes .

    Sometimesthereareothermissingspaces,notthetypicalformthatKennedytalkedabout.ForexampleifIhaveatooth

    Remember this:

    Class I . 2 edentulous areasClass II.1 edentulous area.

  • 7/29/2019 Scr.1 - Removable Partial Dentures

    6/8

    5

    missinghere(thestarinthepicture),whatshouldIcallit??ThereisanApplegatesrulesaysthatIalwayschoosethe posterioredentulouspart,theonethatisthemostposterioristhedistalextension,whichisKennedy'sclassII,whatshouldIcalltheotherspace(hereitsthestar)??ApplegatesaidthatifIhaveanadditionaledentulousareaIdontcaretothenumberofteeth,itcouldbeoneortwo,andeachadditionalmissingspaceiscalleda

    ,notaccordingtothenumberofmissingteethbutaccordingtotheboundedspaces.Sothisis .TheotherproblemwithKennedy'sclassesis,hereIhave ,whatifIhaveteethmissing,herethestarsinthepicture>>>

    Itakethe edentulousareaandtheanteriorspacebecomesa EventhoughitcrossesthemidlinewhichisanotherruleofApplegate(Thereis modificationspacein ).ClassI,II,IIIcanhaveamodification,itscommonsense,ifIhaveclassIVmodificationI(whichcanthappen)itshouldbeclassIIIanyway,hereismyexplanationanyedentulousareaotherthantheoneinclassIVwillbeforsureintheposteriorpartbecauseclassIVshould

    crossthemidlinewhichmeansthatitsanteriortoanyedentulousareasandasApplegatesaidthatwechoosethemostposterior,soifIhaveanyadditionaledentulousareawithclassIVitwilltransformtoamodificationinsteadofaclassbyitself.

    Nowwewilltalkabout3rdmolar:

    manypeoplebornwithout3

    rd

    molarsowecantincludeitinourcalcification(if the third molar is not included in my design, its not included in theclassification ) .

    SometimesthereareteethinthemouththatIdontuseinmydesign.WhatifItellyouthatthisupper3 rdmolarhasnolower3 rdmolarsousuallyinApplegate

  • 7/29/2019 Scr.1 - Removable Partial Dentures

    7/8

    6

    modificationyouwillseethatifthethirdmolarisnotincludedinmydesign,itsnotincludedintheclassificationsoifImnotusingthe3 rdmolar,thisbecomesaunilateralextensionofedentulousareawhichis

    Now this is true for 3rd

    and 2nd

    molar, unless I give you specific information then youhave to take specific default, now again lets go to Applegates rules.

    1-Classification should follow rather than precede extraction:If a patient come to you and has a periodontal disease extract the teeth

    then make the classification, or imagine the patient without that tooth or teeth.

    2- If 3rd molar is missing & not to be replaced, it is not considered in theclassification.

    3-If the 3rd molar is present and to be used as an abutment, it is considered in theclassification.

    4-If the second molar is missing and not to be replaced, it is not considered in theclassification.

    5-The most posterior edentulous area determines the classification.6-Edentulous areas other than those determining classification are called

    modification spaces.

    7-The extent of the modification is not considered, only the number.8-There is no modification space in Class IV.

    If I delete this molar it becomes class II

  • 7/29/2019 Scr.1 - Removable Partial Dentures

    8/8

    7

    ***Nowletustalkaboutveryimportantissue,whichisaboutforcesaffectthedenture,thesupportedtissue,. -Naturalteethconnectedwiththebonebyperiodontalligament(2-4mm),so,itcanmovearound0.5mminalldirection.-Inthecompletedenture,itsfixedonasofttissueabovethebonesotheboneresolvedbutthestoryisthesameinallpartofthemouthso,thepatientcompensatewiththesecondition.-inthepartialdenturetheproblemis:itssupportbysofttissueandteeth

    so,thetoothwhichlocateattheendoftheboundedspacewillaffectedbymoreforce,moreloadbecausethemotionandrotationwillbearounditandwithtimeitwillbelost,BUTourjobistomaintainthehealthytissuewhichisexistthere.So,ifyouhaveteethinonepartofthemouthandnoteethintheotherpartthenyouhaveabigproblem

    so,nowwehaveothertypeofcalcificationwhichdependontheloaddistreputionandsupportform:***inthecompletedenturewehave or

    (alldenturesupportedbytissue).***inthemetalframeworkpartialdenturewehave3story(accordingtokenndysclasses):1-class-III&class-IV(shortspan),wehaveteethinbothsideofboundedspacesowehave . weremovepartofenamelbutnotreachthedentinethenweputthepartialdentureaboveit.2-class-I&class-II,wehavetoothinthefrontandtissueinthebackso;wehave .Andthisistheproblembecausewhenthepatientmasticatehewillcompressthetissueandputmoreloadonthetooth,,,so,nowadaysmostofourstudyistoreducetheseforceandloadtomaintaintheremainingstructureinthemouth.3-Acrylicandinterimpartialdentureandaretissue WHY?Becausetheacrylicmaterialisweakerthanmetalso,itwillruptureif

    weputitabovehardpart(tooth)andbymetalwecanmakethinextensionbutbyacrylicwecantso,itslikethecompletedenture(NOtoothsupported).DONEBY:hebahramadneh! ! !!