中南大口腔颌面医学影像诊断学双语教学课件第8章 牙及牙列的先后天畸形

OralandMaxillofacial

MedicalImaging(8)

XiangyaDentalSchoolDevelopmentalandAcquiredAbnormalitiesofTeethDevelopmentalAnomaliesMicrodontiaSmallerthanaverageMostcommonlyinvolved:Maxillary3rdmolarsMaxillarylaterals(sometimecalled“peg”laterals)MaxillarypremolarsMicrodontiaMicrodontiaMicrodontiaMicrodontiaMACRODONTIALargerThanAverageMACRODONTIAMACRODONTIAMACRODONTIAMACRODONTIAMACRODONTIAGeminationDuringdevelopment,singletoothgermattemptstodivideintotwo.UsuallyresultsinbifurcationofapartofcrownUnilateralorbilateralNormalcomplementofteethispresentGeminationGeminationGeminationFusionDuringdevelopment,unionoftwoadjoiningtoothgermsClinically,identicaltogemination,I.e,’bifurcatedcrown.However,OnetoothismissingUnilateralorbilateralPrimaryorpermanentdentitionFusionFusionFusionFusionGeminationAndFusionHowdoyouclinicallydifferentiatebetweenthetwo?ConcrescenceUnionoftwoteethaftertheyarecompletelyformedJoinedwithcementumConcrescenceConcrescenceConcrescenceDilacerationUnusualangulationofrootsDilacerationDilacerationDilacerationRootBifurcationsRootBifurcationsCongenitallyMissingTeethHypodontia:FewmissingteethOligodontia:Morethanhalfthenumbermissinginanydentition(perm.ordec.)Anodontia:AllteethmissingHypodontiaFrequencyofcongenitallymissingpermanentteeth,inthefollwingorder:3rdmolarsMaxillary2ndpremolarsMandibular2ndpremolarsMaxillarylateralsMandibularcaninesOtherHypodontiaHypodontiaHypodontiaHypodontiaHypodontiaHypodontiaHypodontiaHypodontia

OligodontiaorAnodontiaHereditaryectodermaldysplasiaTherapeuticradiationtojawsatanearlyageHereditaryEctodermalDysplasiaX-linkedrecessiveinmajorityofcases.(rarelyautosomaldominantorrecessive)Affectsectodermally-derivedstructuresThin,dryskinPartialorcompleteabsenceofsweatglandsHyperthermiaHyperpyrexiaHereditaryEctodermalDyslasia(Cont.)Sebaceousglands,hairfolliclesdefectiveorabsentThin,scanty,blondhairDepressedbridgeofnoseFrontalbossingProtuberantlipHereditaryEctodermalDysplasia(Cont.)Completeorpartialabsenceofpermanentteeth(rarely,deciduous)ConeshapedanteriorteethHypoplasiaofoccl./incisalenamelHypoplasiaofminorsalivaryglandsresultinginxerostomiaHereditaryEctodermalDysplasiaHereditaryEctodermalDysplasiaHereditaryEctodermalDysplasiaHereditaryEctodermalDysplasiaHereditaryEctodermalDysplasiaJawIrradiationatEarlyAgeJawIrradiationatEarlyAgeSupernumerary(Hyperdontia)80-85%ofallsupernumeraryinmaxillaNamedinmaxillaonly.NotnamedinmandibleMesiodens.Midlineofmaxilla.85-90%Paramolars.BuccalorlingualtomaxillarymolarsDistomolars(4thmolars,distodens).Distaltomaxillary3rdmolarsMesiodensMesiodensParamolarParamolarDistodens15-20%ofsupernumeraryteetharepresentinthemandible.Inmandible,mostcommonlocationispremolararea.MultipleSupernumeraryTeethCleidocranialdysplasiaGardner’ssyndromeCleidocranialDysplasiaAutosomaldominant,sometimenon-hereditaryMultipleimpacted/uneruptedpermanentteethRetentionofprimaryteethMultiplesupernumeraryteethCleidocranialDysplasiaCleidocranialDysplasiaCleidocranialDysplasiaCleidocranialDysplasia(Cont)CompleteorpartialabsenceofclaviclesbilaterallyCleidocranialDysplasiaCleidocranialDysplasia(Cont.)OpenskullfontanelsandsuturesWormianbonesProminentfrontal,parietalandoccipitalbonesSmallparanasalsinusesCleftpalateGardner’sSyndromeAutosomaldominantMultiplecolo-rectalpolyps,highpotentialforcarcinomatouschangeMultipleosteomasofbonesMultiplesubaceouscystsMultiplesofttissuetumors(fibromas,lipomas,fibrosarcomas)Gardner’sSyndrome(Cont.)Multiplesupernumeraryteethand/orodontomasMultipleimpactedteethGardner’sSyndromeGardner’sSyndromeGardner’sSyndromeGardner’sSyndromeSupernumeraryRootsSupernumeraryRootsSupernumeraryRootsSupernumeraryRootsSupernumeraryRootsInvaginationofalayerofenamelanddentinintopulp.Createsapotentialspaceforentrapmentoffooddebrisandbacteria.Widevariationinsize.Clinically,eithernotdiscernibleorseenasaprominentpitatthecingulum.DensInvaginatus(Dens-in-dente)Frequently,caries,pulpexposureandpariapicalpathologydevelopswithoutanyclinicalindication.Mostfrequently(95%)inmaxillarylateralincisor.Bilateralinhalfthecases.Prophylacticrestorationrecommended.DensInvaginatusDensInvaginatusDensInvaginatusDensInvaginatusDensEvaginatusDensEvaginatusTalonCuspNothereditarySeverehypoplasiaofenamelanddentinUsuallyregional,maybegeneralizedAffectsprimaryandpermanentteethGhost-likeappearanceofteethOdontodysplasiaLargepulpchambersEtiology?Vascularchangesinsofttissues?OdontodysplasiaOdontodysplasiaOdontodysplasiaOdontodysplasiaTaurodontiaBifurcationofmolarpulpchamberintorootcanalsdisplacedapicallyresultinginanextremelylargepulpchamberandshortrootcanals.Usuallyinperm.Molars.Mostpatientsasymptomatic;doesnotrequiretreatment.Frequently,bilateral.TaurodontiaTaurodontiaTaurodontiaDifferentialDx:LargePulpTaurodontiaHypophosphatemicvitaminD-resistantricketsHypophosphatasiaOdontodysplasiaHypophosphatemicVitaminD-resistantRicketsX-linkeddominanttraitHypophosphatemia-duetodecreasedrenaltubularreabsorptionofinorganicphosphatesHyperphosphaturiaNormalserumcalciumAlkalinephosphatasemaybeelevatedHypophosphatemicVitaminD-resistantRickets(cont.)Largepulpchambers,pulphornsextendingtoDEJSingleormultipleperiapicalabscessesSignsofrickets,i.e.,osteomalacia,skeletaldeformities,delayederuptionofteeth,bowingoflegs.ResistanttotherapeuticdosesofVit.DHypophosphatemicVitaminD-resistantRickets(cont.)HypophosphatemicVitaminD-resistantRickets(cont.)HypophosphatemicVitaminD-resistantRickets(cont.)HypophosphatemicVitaminD-resistantRickets(cont.)HypophosphatemicVitaminD-resistantRickets(cont.)HypophosphatemicVitaminD-resistantRickets(cont.)HypophosphatemicVitaminD-resistantRickets(cont.)HypophosphatasiaAutosomalrecessiveDecreasedenzymealkalinephosphataseinserumandtissuesLackofcementumonrootsurfaceLossormobilityofprimaryteethCrestalbonelossEnlargedpulpchambersGreaterpredilectionforpulpexposureandperiapicalpathologySkeletalchangesresemblingricketsHypophosphatasiaHypophosphatasiaHypophosphatasiaVit.D-Res.RicketsVSHypophosphatasiaSimilaritiesEnlargedpulpGreaterpredilectionforperiapicalpathologySkeletalchangesresemblingricketsDissimilaritiesModeofinheritenceNatureofbiochemicaldefectLackofcementumonrootsurfaceMobilityandcrestalbonelossODONTODYSPLASIAODONTODYSPLASIALocalizedEnamelHypoplasia-MiscellaneousCausesLocalorsystemicdisturbancesduringdevelopmentofpermanentteeth.Examples:nutritionaldisturbances,childhoodinfections,etc.Usuallyaffectpermanentanteriorteethandfirstmolarsbilaterally.LocalizedEnamelHypoplasia-MiscellaneousCausesLocalizedEnamelHypoplasia-MiscellaneousCausesLocalizedEnamelHypoplasia-MiscellaneousCausesLocalizedEnamelHypoplasia-MiscellaneousCausesLocalizedEnamelHypoplasia-Turner’sTooth(orTurner’sHypoplasia)Affectsonlyasingletooth,usuallymandibular2ndPremolar,occasionallymax.perm.CentralDuetoinfectionortraumatothepredecessorTurner’sHypoplasiaTurner’sHypoplasiaLocalizedEnamelHypoplasia-CongenitalSyphilisAffectsperm.incisoror1stmolarAffectedincisorisnamedHutchinson’sincisor;1stmolarisnamedmulberrymolarCongenitalSyphilisAmelogenesisImperfectaGeneralizedhereditarydefectofenamel.Sometimenon-hereditary.Affectsalmostallteethinprimaryandpermanentdentitions.Enamelisthinorabsent.Fracturesorwearsawayrapidly.Appearanceofroughenamel.AmelogenesisImperfectaLackofmesialanddistalcontours.Pulpchambersusuallynormalsize.AmelogenesisImperfectaEnamelHyperplasiaAlsocalled“enamelpearls”or“enameldrops”Formationofenamelatthecervicalmarginoftooth,oncementalsurfaceofroot,sometimeinbifurcationortrifurcationEnamelHyperplasiaEnamelHyperplasiaEnamelHyperplasiaEnamelHyperplasiaDentinogenesisImperfectaHereditaryOpalescentDentinDentinogenesisImperfectaAlsonamedhereditaryopalescentdentin.Hereditarydefectofdentin.Autosomaldominanttrait.Colorofteeth:brownish-blueoropalescentbrown.Bothdentitionsaffected.Enamelmaychipaway.Teethmayweardowntoalveolarprocess.DentinogenesisImperfecta(cont.)Bulbouscrownswithconstrictionsattheneck,smallroots,obliteratedpulpchambersandrootcanalsRootfracturescommonHereditaryOpalescentDentinHereditaryOpalescentDentinHereditaryOpalescentDentinHereditaryOpalescentDentinOsteogenesisImperfectaAutosomaldominant.Sometimesnon-hereditaryExtremeporosityandfragilityofbonesSeveredeformityduetofracturesPaleorslatybluescleraFlaccidligamentsTeethidenticaltohereditaryopalescentdentinin50%ofcasesOsteogenesisImperfectaOsteogenesisImperfectaDentinDysplasia(TypeI,II)DentinDysplasiaAutosomaldominanttraitPrimaryandpermanentteethinvolvedSeveralabnormalitiesoccur;onlyfewmaybepresentColornormalinpermanentteeth.PrimaryteethmaybenormalcolororresembleopalescentdentinDentinDysplasia(Cont.)Rootsmaybeshort,blunt,bulgedorabsentCalcifiedmassesinpulp-resultinobliterationordimunitioninsizeofpulpTeethmaybemobileandexfoliatewithminortraumaRadioluscentareasatapicesofteetharegranulomasorradicularcystsDentinDysplasiaDentinDysplasiaDentinDysplasiaDentinDysplasiaDentinDysplasiaPulpCalcificationsDiscrete(PulpStones)DiffusePulpCalcificationsPulpCalcificationsAbnormalNumberofCanals(Accessorycanals)AccessorycanalAccessorycanalAccessorycanalHypercementosisExcessivedepositionofcementumontherootsurface(s).Inmostcases,thecauseisunknown,thepatientisasymptomaticandnotreatmentisrequired.MaybeseeninpatientswithPaget’sdiseaseandhyperpituitarism(acromegaly).HypercementosisHypercementosisHypercementosisHypercementosisGeneralizedHypercementosisPaget’sDiseaseofBoneAcromegalyPaget’sDiseaseofBonePaget’sDiseaseofBoneAnkylosisPeriodontalligamentdisappearsandtoothrootfusestobone.Cause?AnkylosisAnkylosisAnkylosisAbnormalAxialRotationAxialRotationMigrationMigrationMigrationMigrationAtoothismissing.Anothertoothofthesameorsimilarmorphologyispresentatanotherlocation.MigrationMigrationMigrationDriftingDriftingDriftingTranspositionTranspositionTranspositionTransposi