a Types

8/3/2019 a Types

http://slidepdf.com/reader/full/a-types 1/86

8/3/2019 a Types


INTRODUCTIONINTRODUCTION

Lesions derived from the epithelial and or Lesions derived from the epithelial and or

mesenchymal remnants of the tooth formingmesenchymal remnants of the tooth forming

apparatusapparatus

Found exclusively in the mandible and maxillaFound exclusively in the mandible and maxilla

( occasionally – gingiva)( occasionally – gingiva)

Originate from an aberration from the normalOriginate from an aberration from the normal

pattern of odontogenesispattern of odontogenesis A complex group of lesions of diverse A complex group of lesions of diverse

histopathologic types and clinical behavior histopathologic types and clinical behavior

8/3/2019 a Types


INTRODUCTIONINTRODUCTION

Range from hamartomatous proliferations toRange from hamartomatous proliferations tomalignant neoplasms with metastatic capabilitiesmalignant neoplasms with metastatic capabilities

Exhibit varying inductive interactions betweenExhibit varying inductive interactions between

odontogenic epithelium and odontogenicodontogenic epithelium and odontogenic

ectomesenchymeectomesenchyme

8/3/2019 a Types


PresentationPresentation

Asymptomatic Asymptomatic

Jaw expansionJaw expansion Movement of teethMovement of teeth

Root resorptionRoot resorption

Bone lossBone loss

8/3/2019 a Types


8/3/2019 a Types


8/3/2019 a Types


MicroscopyMicroscopy

Mimic cell / tissue of originMimic cell / tissue of origin

Resemble the soft tissues of the enamel organResemble the soft tissues of the enamel organ

or dental pulp or may contain hard tissueor dental pulp or may contain hard tissue

elements of enamel, dentin, & or cementumelements of enamel, dentin, & or cementum

8/3/2019 a Types


CLASSIFICATIONCLASSIFICATION

WHO (1992)WHO (1992)

ODONTOGENIC TUMORS

BENIGN MALIGNANT

8/3/2019 a Types


MODIFIED WHO CLASSIFICATIONMODIFIED WHO CLASSIFICATION

BENIGNBENIGN

I Odontogenic epithelium withoutI Odontogenic epithelium without

odontogenic ectomesenchymeodontogenic ectomesenchymeAmeloblastomaAmeloblastoma

Squamous odontogenic tumor Squamous odontogenic tumor

Calcifying epithelial odontogenic tumor Calcifying epithelial odontogenic tumor

Adenomatoid odontogenic tumor Adenomatoid odontogenic tumor

8/3/2019 a Types



II Odontogenic epithelium with odontogenicII Odontogenic epithelium with odontogenic

ectomesenchyme with or without hard tissueectomesenchyme with or without hard tissue

formationformation

Ameloblastic fibromaAmeloblastic fibroma Ameloblastic fibrodentinomaAmeloblastic fibrodentinoma

Ameloblastic fibro-odontomaAmeloblastic fibro-odontoma

OdontoameloblastomaOdontoameloblastoma

Calcifying odontogenic cystCalcifying odontogenic cyst

Complex odontomaComplex odontoma

Compound odontomaCompound odontoma

8/3/2019 a Types


III Odontogenic ectomesenchyme with or III Odontogenic ectomesenchyme with or

without included odontogenicwithout included odontogenic

epitheliumepitheliumOdontogenic fibromaOdontogenic fibroma

Myxoma (myxofibroma)Myxoma (myxofibroma)

Cementoblastoma (benignCementoblastoma (benign

cementoblastoma, true cementoma)cementoblastoma, true cementoma)


8/3/2019 a Types


B. MALIGNANTB. MALIGNANT

I Odontogenic CarcinomasI Odontogenic Carcinomas

Malignant ameloblastomaMalignant ameloblastomaPrimary intraosseous carcinomaPrimary intraosseous carcinoma

Clear cell odontogenic carcinomaClear cell odontogenic carcinoma

Ghost cell odontogenic carcinomaGhost cell odontogenic carcinoma


8/3/2019 a Types


II Odontogenic SarcomasII Odontogenic SarcomasAmeloblastic fibrosarcomaAmeloblastic fibrosarcoma

Ameloblastic fibro dentinosarcomaAmeloblastic fibro dentinosarcoma

Ameloblastic fibro odontosarcomaAmeloblastic fibro odontosarcoma

8/3/2019 a Types


2005 WHO2005 WHO

HISTOLOGICALHISTOLOGICAL

CLASSIFICATION OFCLASSIFICATION OF

ODONTOGENIC TUMOURSODONTOGENIC TUMOURS

8/3/2019 a Types


BENIGN TUMOURS1. Odontogenic epithelium with mature, fibrous

stroma without odontogenicectomesenchyme

Ameloblastoma, solid / multicystic type extraosseous / peripheral type desmoplastic type unicystic type

Squamous odontogenic tumour Calcifying epithelial odontogenic tumour Adenomatoid odontogenic tumour Keratocystic odontogenic tumour

8/3/2019 a Types


2. Odontogenic epithelium with odontogenicectomesenchyme,with or without hard tissueformation

Ameloblastic fibroma Ameloblastic fibrodentinoma

Ameloblastic fibro-odontomaComplex OdontomaCompound OdontomaOdontoameloblastomaCalcifying cystic odontogenic tumour Dentinogenic ghost cell tumour

8/3/2019 a Types


3. Mesenchyme and/or odontogenic

ectomesenchyme with or without

odontogenic epithelium

Odontogenic fibroma

Odontogenic myxoma / myxofibroma

Cementoblastoma

8/3/2019 a Types


MALIGNANT TUMOURS

1. Odontogenic carcinomas

Metastasizing (malignant) ameloblastoma

Ameloblastic carcinomaPrimary intraosseous squamous cell

carcinoma

Clear cell odontogenic carcinomaGhost cell odontogenic carcinoma

8/3/2019 a Types


2. Odontogenic sarcomas

Ameloblastic fibrosarcoma

Ameloblastic fibrodentino andfibro-odontosarcoma

8/3/2019 a Types


AMELOBLASTOMA AMELOBLASTOMA

Introduction & definitionIntroduction & definitionTypesTypes

IncidenceIncidenceClinical featuresClinical featuresRadiographic featuresRadiographic features

HistogenesisHistogenesisHistopathology – subtypesHistopathology – subtypesTreatment and PrognosisTreatment and Prognosis

8/3/2019 a Types


UNICYSTIC AMELOBLASTOMAUNICYSTIC AMELOBLASTOMA

Peripheral AmeloblastomaPeripheral Ameloblastoma

Pitutary AmeloblastomaPitutary Ameloblastoma Adamntinoma of long bones Adamntinoma of long bones

8/3/2019 a Types


AMELOBLASTOMA AMELOBLASTOMA

SYNONYMSSYNONYMS

Adamantinoma Adamantinoma

Adamantoblastoma AdamantoblastomaMultilocular cystMultilocular cyst

8/3/2019 a Types


Definition (Robinson)Definition (Robinson)

It is a tumor of odontogenic origin (derivedIt is a tumor of odontogenic origin (derived

from enamel organ type tissue which doesfrom enamel organ type tissue which does

not undergo differentiation to the point of not undergo differentiation to the point of

enamel formation) usually unicentric, non-enamel formation) usually unicentric, non-functional, intermittent in growth,functional, intermittent in growth,

anatomically benign and clinicallyanatomically benign and clinically

persistentpersistent

Ivy and Churchill – ameloblastoma (1934)Ivy and Churchill – ameloblastoma (1934)

8/3/2019 a Types


TypesTypes

Certain behaviour patterns, anatomic locations,Certain behaviour patterns, anatomic locations,

histologic and radiologic featureshistologic and radiologic features

Ameloblastoma

Central

(Intraosseous)

Peripheral

(Extraosseous)

Solid / multicystic (86%)Unicystic (13%) Desmoplastic

8/3/2019 a Types


IncidenceIncidence

Common odontogenic tumor Common odontogenic tumor

11% of all tumors and cysts of jaws

18 % of odontogenic neoplasms

8/3/2019 a Types


Conventional Solid / multicystic

Intraosseous Ameloblastoma

Most frequently encounteredMost frequently encountered

Demographics :Demographics :

Age : Age : wide age rangewide age range

3-73-7thth decades of lifedecades of life

Sex : no gender predilectionSex : no gender predilectionRace : blacksRace : blacks

8/3/2019 a Types


Clinical featuresClinical features

Site :Site :

8585 % - mandible – molar – ascending

ramus area

15 % - maxilla – posterior region

Usually asymptomatic

Pain & paresthesia – uncommonSmaller lesions – only on routine R/F

8/3/2019 a Types


8/3/2019 a Types


A painless swelling / expansion of the A painless swelling / expansion of the

jaw ; tends to expand the bone rather than jaw ; tends to expand the bone rather than

perforate itperforate it

Very thin bone – ‘EGG – SHELLVery thin bone – ‘EGG – SHELL

CRACKLING’ on palpationCRACKLING’ on palpation

Tooth mobilityTooth mobility

Unhealed extraction sitesUnhealed extraction sites

aggressiveaggressive

8/3/2019 a Types


MaxillaMaxilla

Facial swelling, nasal obstructionFacial swelling, nasal obstruction

Sinus involvement, extension into the orbitSinus involvement, extension into the orbitor nasopharynxor nasopharynx

Sinusitis, pre auricular painSinusitis, pre auricular pain

Foul smelling dischargeFoul smelling discharge

8/3/2019 a Types


Radiographic featuresRadiographic features

Often – multilocular radiolucent lesionOften – multilocular radiolucent lesion

Rarely – unilocular Rarely – unilocular

Large loculations – ‘soap bubble’Large loculations – ‘soap bubble’appearanceappearance

Small loculations – ‘honey combed’Small loculations – ‘honey combed’

appearanceappearance

8/3/2019 a Types


8/3/2019 a Types


8/3/2019 a Types


8/3/2019 a Types



Buccal & lingual cortical expansion andBuccal & lingual cortical expansion and

thinningthinning

Resorption of rootsResorption of roots

Displacement of teethDisplacement of teeth

Association with an unerupted tooth Association with an unerupted tooth

(mandibular 3(mandibular 3rdrd

molar)molar)

Irregular scalloping of the margins of R/LIrregular scalloping of the margins of R/L

lesionslesions

Sinus – antral clouding / opacitySinus – antral clouding / opacity

8/3/2019 a Types


Differential diagnosisDifferential diagnosis

OKCOKC

ABC ABCCentral hemangiomaCentral hemangioma

Brown tumor Brown tumor


8/3/2019 a Types


HISTOGENESISHISTOGENESIS

Tumor may be derived fromTumor may be derived from Cell rests of enamel organCell rests of enamel organ Cell rests of SerreCell rests of Serre

Cell rests of MalassezCell rests of Malassez Epithelium of Odontogenic cystsEpithelium of Odontogenic cysts Disturbances in developing enamel organDisturbances in developing enamel organ Basal cells of surface epitheliumBasal cells of surface epithelium Heterotopic epithelium in other parts of the bodyHeterotopic epithelium in other parts of the body

(extragnathic ameloblastoma)(extragnathic ameloblastoma) E.g. pituitary gland and long bonesE.g. pituitary gland and long bones

8/3/2019 a Types


PathologyPathology

Macroscopy / grossMacroscopy / gross

Grayish white or grayish yellow cylindricalGrayish white or grayish yellow cylindrical

or fusiform massor fusiform mass

Small or large cystic spacesSmall or large cystic spaces

8/3/2019 a Types


Microscopy (h/p)Microscopy (h/p)

6 subtypes / variants6 subtypes / variants

Follicular Follicular

PlexiformPlexiform Acantomatous Acantomatous

Granular cellGranular cell

Basal cellBasal cellDesmoplasticDesmoplastic

8/3/2019 a Types



Follicular patternFollicular patternMost common and recognizable patternMost common and recognizable pattern

Discrete islands or follicles of epithelialDiscrete islands or follicles of epithelial

cells in a mature connective tissue stromacells in a mature connective tissue stromaEpithelial islands – resemble enamelEpithelial islands – resemble enamel

organ of the developing tooth germ ; :organ of the developing tooth germ ; :

8/3/2019 a Types


Consist of:Consist of:

Peripheral cells (ameloblast like cells)Peripheral cells (ameloblast like cells)

Coumnar basal cells with hyperchromaticCoumnar basal cells with hyperchromatic

nucleinuclei

Nuclear palisading with polarizationNuclear palisading with polarization

Cytoplasmic vacuolationCytoplasmic vacuolation

Central cells – loosely arranged and resembleCentral cells – loosely arranged and resemble

stellate reticulumstellate reticulum

8/3/2019 a Types


Cyst formation –Cyst formation – commoncommonMicrocyst – large macroscopic cystsMicrocyst – large macroscopic cysts

Hyalinization around the follicles – because of Hyalinization around the follicles – because of induction phenomenoninduction phenomenon

StromaStroma

Mature fibrous connective tissue in variableMature fibrous connective tissue in variableamountsamounts

Plentiful or very minimalPlentiful or very minimal


8/3/2019 a Types


8/3/2019 a Types


Mi

8/3/2019 a Types


Plexiform patternPlexiform pattern

Epithelium –Epithelium –Long, anastomosing cords or larger Long, anastomosing cords or larger

sheets bounded by single layer columnar sheets bounded by single layer columnar or cuboidal ameloblast like cellsor cuboidal ameloblast like cellssurrounding more loosely arrangedsurrounding more loosely arranged

epithelial cellsepithelial cellsStroma –Stroma –Loosely arranged and vascular Loosely arranged and vascular

Cyst formation -- uncommonCyst formation -- uncommon


8/3/2019 a Types


8/3/2019 a Types


8/3/2019 a Types


8/3/2019 a Types


Acanthomatous pattern Acanthomatous pattern

Extensive squamous metaplasia, oftenExtensive squamous metaplasia, often

with keratin formation in the centralwith keratin formation in the central

portions of a follicleportions of a follicle

Mistaken for Mistaken for Squamous cell carcinomaSquamous cell carcinoma

Squamous odontogenic tumor Squamous odontogenic tumor


8/3/2019 a Types


8/3/2019 a Types


8/3/2019 a Types


8/3/2019 a Types


MiMi

8/3/2019 a Types


Basal cell patternBasal cell pattern

Least common typeLeast common type

Nests of uniform basaloid cellsNests of uniform basaloid cellsH/p – similar to BCC of skinH/p – similar to BCC of skin

No stellate reticulum in the central portionsNo stellate reticulum in the central portions

of the nestsof the nestsPeripheral cells – cuboidal rather thanPeripheral cells – cuboidal rather than

columnar columnar


8/3/2019 a Types


8/3/2019 a Types


Desmoplastic ameloblastoma

Eversole et al, 1984

Considered as a separate type:Different clinical features

Different radiological features

Different histopathological features

8/3/2019 a Types


Desmoplastic ameloblastomaDesmoplastic ameloblastoma

Desmoplasia – extensive stromalDesmoplasia – extensive stromal

collagenization( hyalinization)collagenization( hyalinization)

Hypocellular Hypocellular

Tendency to grow in thin strands and cords of Tendency to grow in thin strands and cords of epi rather than in an island like patteren.epi rather than in an island like patteren.

Epithelium compressed and fragmentedEpithelium compressed and fragmented

Scant central cells with peripheral flat cells.Scant central cells with peripheral flat cells. Site : maxilla > mandibleSite : maxilla > mandible

Histogenesis : cell rests of MalassezHistogenesis : cell rests of Malassez

8/3/2019 a Types


RADIOLOGICAL FEATURES

Mixed radiolucent & radio-opaque

lesion

Unilocular or Multilocular Borders poorly defined

DIFFERENTIAL DIAGNOSIS:Fibro-osseous lesions

8/3/2019 a Types


HISTOPATHOLOGY

STROMA:

Desmoplasia

Thick collagen bundles squeeze theepithelial islands

New bone formation

8/3/2019 a Types


HISTOPATHOLOGY

ODONTOGENIC EPITHELIUM:

Islands compressed by the collagen

bundles (ANIMAL-LIKE; KITE-LIKE)

Peripheral cells: cuboidal

No ameloblast-like cells

Central cells: spindle / polygonalNo stellate reticulum-like cells

8/3/2019 a Types


8/3/2019 a Types


8/3/2019 a Types


Treatment and prognosisTreatment and prognosis

A variety of treatment modalities A variety of treatment modalities

Simple enucleation and curettage to en blocSimple enucleation and curettage to en bloc

resectionresection Curettage – higher recurrence rate (50Curettage – higher recurrence rate (50 – 90 %) – 90 %)

Marginal / bloc resection – most widely usedMarginal / bloc resection – most widely used

Recurrence rate -- 15 %Recurrence rate -- 15 %


8/3/2019 a Types



Conventional ameloblastomaConventional ameloblastoma A persistent, infiltrative neoplasm A persistent, infiltrative neoplasm

Progressive spread to vital structuresProgressive spread to vital structures

DeathDeath

Many of these tumors – not lifeMany of these tumors – not life

threatening lesionsthreatening lesions

rarely – frank malignant behavior rarely – frank malignant behavior

8/3/2019 a Types



A unilocular cystic lesion whose clinical A unilocular cystic lesion whose clinical

features resemble those of a non neoplasticfeatures resemble those of a non neoplastic

cystcyst

A distinct entity based on clinical, A distinct entity based on clinical,

radiographic & pathologic features and itsradiographic & pathologic features and its

response to treatmentresponse to treatment

10 - 1510 - 15% of all intraosseous% of all intraosseousameloblastomasameloblastomas


8/3/2019 a Types



Clinical featuresClinical features Age : Age :Younger patientsYounger patients

22ndnd

decadedecadeSex : no predilectionSex : no predilection

Site : posterior mandible (90Site : posterior mandible (90 % cases)% cases)

Presentation :Presentation : Asymptomatic Asymptomatic

Large lesions – painless swelling of the jawsLarge lesions – painless swelling of the jaws


8/3/2019 a Types



May or may not be associated with anMay or may not be associated with an

impacted toothimpacted tooth

Well – defined radiolucencies ; may or Well – defined radiolucencies ; may or

may not be demarcated by a perilesionalmay not be demarcated by a perilesional

corticated rimcorticated rim

8/3/2019 a Types


8/3/2019 a Types



8/3/2019 a Types


HistogenesisHistogenesis

Proposed theoriesProposed theoriesCystic degeneration of solidCystic degeneration of solid

ameloblastomasameloblastomas Ameloblastomatous change in an Ameloblastomatous change in an

preexisting cystpreexisting cyst

Co – existence of non-neoplastic andCo – existence of non-neoplastic andneoplastic epitheliumneoplastic epithelium

De novoDe novo

U C S C O S O


8/3/2019 a Types


Association with a cyst Association with a cyst

Most common --Most common -- dentigerous cystdentigerous cyst

Other cysts --Other cysts --Parakeratinized OKCParakeratinized OKC

Radicular cystRadicular cyst

Residual cystResidual cyst

COCCOC

GOCGOC



8/3/2019 a Types


HistopathologyHistopathology

3 distinct patterns3 distinct patterns

1.1. LuminalLuminal

2.2. IntraluminalIntraluminal

3.3. MuralMural

8/3/2019 a Types



8/3/2019 a Types


LuminalLuminal

Unilocular cystic lesion lined by epithelium (basalUnilocular cystic lesion lined by epithelium (basal

cells –cells – VICKERS-GORLIN CRITERIAVICKERS-GORLIN CRITERIA))

No infiltrating neoplastic epitheliumNo infiltrating neoplastic epithelium Tumor confined to luminal surface of the cystTumor confined to luminal surface of the cyst

luminal unicystic ameloblastomaluminal unicystic ameloblastoma

Cells overlying the basal layer – looselyCells overlying the basal layer – looselycohesive and resemble stellate reticulumcohesive and resemble stellate reticulum

8/3/2019 a Types


VICKERS-GORLIN CRITERIA

Columnar basal cells with

hyperchromatic nuclei

Nuclear palisading with polarization

Cytoplasmic vacuolation withintercellular spacing

Subepithelial hyalanization


8/3/2019 a Types


IntraluminalIntraluminalUnilocular cystic lesion in which a noduleUnilocular cystic lesion in which a nodule

arises from the epithelium and projectsarises from the epithelium and projects

into the lumen of the cystinto the lumen of the cystNodules – odontogenic epithelium thatNodules – odontogenic epithelium that

may sometimes resemble plexiformmay sometimes resemble plexiformameloblastomaameloblastoma

Part of the lining – V & G criteriaPart of the lining – V & G criteriaNo infiltration into the cyst wallNo infiltration into the cyst wall


8/3/2019 a Types


MuralMural

Unilocular cystic lesion – islands of Unilocular cystic lesion – islands of

ameloblastomatous epithelium (follicular /ameloblastomatous epithelium (follicular /

plexiform) in the fibrous cyst wallplexiform) in the fibrous cyst wallMay or may not be connected to the liningMay or may not be connected to the lining

Part of cystic lining – V & G criteriaPart of cystic lining – V & G criteria

Mural + Intraluminal prolierationsMural + Intraluminal prolierations

8/3/2019 a Types


8/3/2019 a Types



8/3/2019 a Types


DIAGNOSIS OF UA – ONLY AFTERDIAGNOSIS OF UA – ONLY AFTER

MICROSCOPIC EXAMINATIONMICROSCOPIC EXAMINATION

Treatment and PrognosisTreatment and Prognosis

Luminal & intraluminal variants –Luminal & intraluminal variants –

conservative approachconservative approach

Mural -- radical resectionMural -- radical resection

Recurrence rates – 10 - 20Recurrence rates – 10 - 20% after % after

enucleation & curettageenucleation & curettage

UNICYSTIC AMELOBLASTOMA

8/3/2019 a Types


8/3/2019 a Types


8/3/2019 a Types


8/3/2019 a Types


8/3/2019 a Types


8/3/2019 a Types


Documents

a Types