09 Odont Tumor

Odontogenic Odontogenic TumorsTumors

Classification of Classification of Odontogenic Tumors*Odontogenic Tumors*

I.I. Tumors of odontogenic epitheliumTumors of odontogenic epithelium A.A. AmeloblastomaAmeloblastoma

1. Malignant ameloblastoma1. Malignant ameloblastoma2. Ameloblastic carcinoma2. Ameloblastic carcinoma

B.B. Clear cell odontogenic carcinomaClear cell odontogenic carcinoma C.C. Adenomatoid odontogenic tumorAdenomatoid odontogenic tumor D.D. Calcifying epithelial odontogenic tumorCalcifying epithelial odontogenic tumor E.E. Squamous odontogenic tumorSquamous odontogenic tumor

II.II. Mixed odontogenic tumorsMixed odontogenic tumors A.A. Ameloblastic fibromaAmeloblastic fibroma B.B. Ameloblastic fibro-odontomaAmeloblastic fibro-odontoma C.C. Ameloblastic fibrosarcomaAmeloblastic fibrosarcoma D.D. OdontoameloblastomaOdontoameloblastoma E.E. Compound odontomaCompound odontoma F.F. Complex odontomaComplex odontoma

III. Tumors of odontogenic ectomesenchymeIII. Tumors of odontogenic ectomesenchyme A.A. Odontogenic fibromaOdontogenic fibroma B.B. Granular cell odontogenic tumorGranular cell odontogenic tumor C.C. Odontogenic myxomaOdontogenic myxoma D.D. CementoblastomaCementoblastoma

* From Neville, et al.* From Neville, et al.

BENIGN, NO RECURRENCE BENIGN, NO RECURRENCE POTENTIAL POTENTIAL

Adenomatoid odontogenic Adenomatoid odontogenic tumor tumor

Squamous odontogenic Squamous odontogenic tumor tumor

Cementoblastoma Cementoblastoma Periapical cementoosseous Periapical cementoosseous

dysplasia dysplasia Odontoma Odontoma

BENIGN, SOME BENIGN, SOME RECURRENCE POTENTIAL RECURRENCE POTENTIAL

Cystic ameloblastoma Cystic ameloblastoma (unicystic)(unicystic)

Calcifying epithelial Calcifying epithelial odontogenic tumor odontogenic tumor

Central odontogenic fibroma Central odontogenic fibroma Florid cementoosseous Florid cementoosseous

dysplasia dysplasia Ameloblastic fibroma and Ameloblastic fibroma and

fibroodontoma fibroodontoma *From Regezi, et al.*From Regezi, et al.

BENIGN AGGRESSIVE BENIGN AGGRESSIVE Ameloblastoma Ameloblastoma Clear cell odontogenic Clear cell odontogenic

tumor (some consider this tumor (some consider this a carcinoma)a carcinoma)

Odontogenic ghost cell Odontogenic ghost cell tumor (COC, solid type)tumor (COC, solid type)

Odontogenic myxoma Odontogenic myxoma Odontoameloblastoma Odontoameloblastoma

MALIGNANT MALIGNANT Malignant ameloblastoma Malignant ameloblastoma Ameloblastic carcinoma Ameloblastic carcinoma Primary intraosseous Primary intraosseous

carcinoma carcinoma Odontogenic ghost cell Odontogenic ghost cell

carcinoma carcinoma Ameloblastic fibrosarcoma Ameloblastic fibrosarcoma

Biologic Classification of Odontogenic Tumors*Biologic Classification of Odontogenic Tumors*

Tumors of Tumors of Odontogenic Odontogenic EpitheliumEpithelium

AmeloblastomaAmeloblastoma

The ameloblastoma is the most The ameloblastoma is the most common common clinically significantclinically significant (not (not the most common) odontogenic the most common) odontogenic tumor. tumor.

It may develop from cell rests of the It may develop from cell rests of the enamel organ; from the developing enamel organ; from the developing enamel organ; from the lining of enamel organ; from the lining of odontogenic cysts or from the basal odontogenic cysts or from the basal cells of the oral mucosa.cells of the oral mucosa.


It is typically slow-growing, locally It is typically slow-growing, locally invasive and runs a benign course.invasive and runs a benign course.

H.G.B. Robinson described it as H.G.B. Robinson described it as being a benign tumor that is “usually being a benign tumor that is “usually unicentric, non-functional, unicentric, non-functional, intermittent in growth, anatomically intermittent in growth, anatomically benign and clinically persistent.”benign and clinically persistent.”


Ameloblastomas occur in 3 different Ameloblastomas occur in 3 different clinico-radiographic situations clinico-radiographic situations requiring different therapeutic requiring different therapeutic considerations and having different considerations and having different prognoses.prognoses. Conventional Solid/Multicystic (86 % of all Conventional Solid/Multicystic (86 % of all

cases)cases) Unicystic (13 % of all cases)Unicystic (13 % of all cases) Peripheral or Extraosseous (1 % of all Peripheral or Extraosseous (1 % of all

cases)cases)

Solid or Multicystic Solid or Multicystic Ameloblastoma: Clinical Ameloblastoma: Clinical

FeaturesFeatures Patient Age: Approximately equal frequency Patient Age: Approximately equal frequency

from the third through the seventh decades.from the third through the seventh decades. Sex Predilection: Approximately equal.Sex Predilection: Approximately equal. Location: 80 % in mandible; 70 % in posterior Location: 80 % in mandible; 70 % in posterior

regions.regions. Radiographic Appearance: Radiolucent lesion Radiographic Appearance: Radiolucent lesion

which is usually well-circumscribed; it may which is usually well-circumscribed; it may be unilocular or multilocular (soap-bubble, be unilocular or multilocular (soap-bubble, honeycomb); occasionally an ameloblastoma honeycomb); occasionally an ameloblastoma will be ill-defined with a ragged border.will be ill-defined with a ragged border.

Solid or Multicystic Solid or Multicystic Ameloblastoma: Histologic Ameloblastoma: Histologic

FeaturesFeatures There are several microscopic subtypes There are several microscopic subtypes

but these generally have little bearing but these generally have little bearing on the behavior of the tumor.on the behavior of the tumor.

The follicular and plexiform types are The follicular and plexiform types are the most common.the most common.

The The follicularfollicular type is composed of type is composed of islands of epithelium which resemble islands of epithelium which resemble the enamel organ in a mature fibrous the enamel organ in a mature fibrous connective tissue stoma.connective tissue stoma.


FeaturesFeatures The The plexiform plexiform type is composed of type is composed of

long, anastomosing cords or larger long, anastomosing cords or larger sheets of odontogenic epithelium. sheets of odontogenic epithelium. Its stroma tends to be loose and Its stroma tends to be loose and more vascular.more vascular.

TheThe acanthomatous acanthomatous type shows type shows evidence of extensive squamous evidence of extensive squamous metaplasia with keratin formation in metaplasia with keratin formation in the island of odontogenic epithelium.the island of odontogenic epithelium.


FeaturesFeatures In the In the granular cellgranular cell type there is type there is

transformation of groups of transformation of groups of epithelial cells to granular cells; the epithelial cells to granular cells; the nature of the granular change is nature of the granular change is unknown. This type is more unknown. This type is more common in young patients and has common in young patients and has been shown to be clinically been shown to be clinically aggressive.aggressive.


FeaturesFeatures The The desmoplasticdesmoplastic form is composed form is composed

of islands/cords of odontogenic of islands/cords of odontogenic epithelium in a very dense collagenous epithelium in a very dense collagenous stroma. It has a predilection for the stroma. It has a predilection for the anterior maxilla and because of the anterior maxilla and because of the dense connective tissue may appear as dense connective tissue may appear as a radiolucent-radiopaque lesion.a radiolucent-radiopaque lesion.

The The basaloid basaloid type is the least common type is the least common and is composed of uniform basaloid and is composed of uniform basaloid cells with no stellate reticulum.cells with no stellate reticulum.

Solid or Multicystic Solid or Multicystic Ameloblastoma: Additional Ameloblastoma: Additional

FeaturesFeatures In some studies solid/multicystic In some studies solid/multicystic

ameloblastomas are reported to be ameloblastomas are reported to be more common in Blacks.more common in Blacks.

While lesions are generally While lesions are generally asymptomatic, ameloblastomas may asymptomatic, ameloblastomas may cause paresthesia, pain particularly cause paresthesia, pain particularly if infected and they can erode the if infected and they can erode the cortical palates.cortical palates.

Solid or Multicystic Solid or Multicystic Ameloblastoma: TreatmentAmeloblastoma: Treatment Treatments have ranged from simple Treatments have ranged from simple

enucleation and curettage to en bloc enucleation and curettage to en bloc resection.resection.

Marginal resection is the most widely Marginal resection is the most widely used method of treatment with the least used method of treatment with the least recurrences reported (up to 15 %).recurrences reported (up to 15 %).

Most surgeons advocate a margin of at Most surgeons advocate a margin of at least 1.0 cm beyond the radiographic least 1.0 cm beyond the radiographic limits of the tumor as the tumor often limits of the tumor as the tumor often extends beyond the apparent extends beyond the apparent radiologic/clinical margins.radiologic/clinical margins.

Solid or Multicystic Solid or Multicystic Ameloblastoma: PrognosisAmeloblastoma: Prognosis

Treatment with curettage has resulted in Treatment with curettage has resulted in recurrence rates ranging from 55-90 %.recurrence rates ranging from 55-90 %.

Treatment with marginal resection has Treatment with marginal resection has resulted in approximately a 15 % resulted in approximately a 15 % recurrence rate.recurrence rate.

Ameloblastomas of this type arising in the Ameloblastomas of this type arising in the maxilla are particularly dangerous as it is maxilla are particularly dangerous as it is often difficult in getting adequate margins.often difficult in getting adequate margins.

Rarely is an ameloblastoma life Rarely is an ameloblastoma life threatening.threatening.

Unicystic Ameloblastoma: Unicystic Ameloblastoma: Clinical FeaturesClinical Features

Patient Age: The patients are younger Patient Age: The patients are younger than those with the solid/multicystic form. than those with the solid/multicystic form. 50% are diagnosed during the second 50% are diagnosed during the second decade of life.decade of life.

Sex Predilection: ? Same as for the solid??Sex Predilection: ? Same as for the solid?? Location: 90 % occur in the mandible Location: 90 % occur in the mandible

usually in the posterior region.usually in the posterior region. Radiographic Appearance: Typically Radiographic Appearance: Typically

appears as a RL around the crown of an appears as a RL around the crown of an unerupted tooth (most commonly a unerupted tooth (most commonly a mandibular third molar).mandibular third molar).

Unicystic Ameloblastoma: Unicystic Ameloblastoma: Histologic FeaturesHistologic Features

Three histopathologic variants are Three histopathologic variants are recognized: recognized: Luminal: the tumor is confined to the Luminal: the tumor is confined to the

luminal surface of the cyst.luminal surface of the cyst. Intraluminal/plexiform: the tumor Intraluminal/plexiform: the tumor

projects from the cystic lining; projects from the cystic lining; sometimes resembles the plexiform type sometimes resembles the plexiform type of solid/multicystic ameloblastoma.of solid/multicystic ameloblastoma.

Mural: the tumor infiltrates the fibrous Mural: the tumor infiltrates the fibrous cystic wall.cystic wall.

Unicystic Ameloblastoma: Unicystic Ameloblastoma: Treatment and PrognosisTreatment and Prognosis

Enucleation of the cyst is probably Enucleation of the cyst is probably adequate for the luminal and adequate for the luminal and intraluminal/plexiform types.intraluminal/plexiform types.

Treatment of the mural type is Treatment of the mural type is controversial with some surgeons controversial with some surgeons believing that local resection is best.believing that local resection is best.

10-20 % recurrence after 10-20 % recurrence after enucleation and curettage with all enucleation and curettage with all unicystic ameloblastomas.unicystic ameloblastomas.

Peripheral Peripheral AmeloblastomaAmeloblastoma

These tumors are extraosseous and These tumors are extraosseous and therefore occupy the lamina propria therefore occupy the lamina propria underneath the surface epithelium underneath the surface epithelium but outside of the bone.but outside of the bone.

Histologically, these lesions have the Histologically, these lesions have the same features as the intraosseous same features as the intraosseous forms of the tumor.forms of the tumor.

Peripheral Ameloblastoma: Peripheral Ameloblastoma: Clinical FeaturesClinical Features

Patient Age: Wide age range but most Patient Age: Wide age range but most occur during middle-age.occur during middle-age.

Gender Predilection: This is not Gender Predilection: This is not known.known.

Location: Posterior gingival/alveolar Location: Posterior gingival/alveolar mucosa is involved most frequently. mucosa is involved most frequently. There is a slight predilection for the There is a slight predilection for the mandible. The buccal mucosa has mandible. The buccal mucosa has been the site in a few reported cases.been the site in a few reported cases.

Peripheral Ameloblastoma: Peripheral Ameloblastoma: Radiographic & Histologic Radiographic & Histologic

FeaturesFeatures Radiographic Appearance: Although Radiographic Appearance: Although

not in bone, a few cases have shown not in bone, a few cases have shown superficial erosion of the alvelolar bone.superficial erosion of the alvelolar bone.

Histologic Appearance: Islands of Histologic Appearance: Islands of ameloblastic epithelium are observed in ameloblastic epithelium are observed in the lamina propria; plexiform and the lamina propria; plexiform and follicular patterns are the most follicular patterns are the most common; in 50 % of the cases the common; in 50 % of the cases the tumor connects with the basal cell layer tumor connects with the basal cell layer of the surface epithelium.of the surface epithelium.

Peripheral Ameloblastoma: Peripheral Ameloblastoma: Treatment and PrognosisTreatment and Prognosis

Unlike its intraosseous counterpart, this Unlike its intraosseous counterpart, this tumor has an innocuous clinical behavior.tumor has an innocuous clinical behavior.

Patients respond well to local surgical Patients respond well to local surgical excision.excision.

Some reports indicate a 25 % recurrence Some reports indicate a 25 % recurrence rate but in these cases as second surgical rate but in these cases as second surgical procedure results in cure.procedure results in cure.

There has been a rare malignant change There has been a rare malignant change reported.reported.

Malignant Ameloblastoma Malignant Ameloblastoma and Ameloblastic and Ameloblastic

CarcinomaCarcinoma Less than 1 % of the ameloblastomas show Less than 1 % of the ameloblastomas show

malignant behavior with the development of malignant behavior with the development of metastases.metastases.

Malignant ameloblastomaMalignant ameloblastoma is a tumor that is a tumor that shows histologic features of the typical shows histologic features of the typical (benign) ameloblastoma in both the primary (benign) ameloblastoma in both the primary and secondary deposits.and secondary deposits.

Ameloblastic carcinomaAmeloblastic carcinoma is a tumor that is a tumor that shows cytologic features of malignancy in the shows cytologic features of malignancy in the primary tumor, in recurrence and any primary tumor, in recurrence and any metastases.metastases.

Malignant Ameloblastoma Malignant Ameloblastoma & Ameloblastic Carcinoma: & Ameloblastic Carcinoma:

ClinicalClinical Patients range in age from 4-75 with a Patients range in age from 4-75 with a

mean of 30 years.mean of 30 years. Metastasis has occurred from 1-30 Metastasis has occurred from 1-30

years after the initial treatment.years after the initial treatment. Metastases most often occur in the Metastases most often occur in the

lungs and in the case of malignant lungs and in the case of malignant ameloblastoma raises the question of ameloblastoma raises the question of aspiration during surgery. Spread has aspiration during surgery. Spread has also occurred to the cervical lymph also occurred to the cervical lymph nodes and to vertebrae and viscera.nodes and to vertebrae and viscera.


X-Ray X-Ray With the malignant ameloblastoma, With the malignant ameloblastoma,

the appearance is similar to the the appearance is similar to the typical solid/multicystic typical solid/multicystic ameloblastoma.ameloblastoma.

The ameloblastic carcinoma is often The ameloblastic carcinoma is often more aggressive with the lesion more aggressive with the lesion appearing as an ill-defined appearing as an ill-defined radiolucency with cortical radiolucency with cortical destruction.destruction.


HistologyHistology With the malignant ameloblastoma, With the malignant ameloblastoma,

both the primary and metastases both the primary and metastases show no microscopic features that show no microscopic features that differ from those of the typical differ from those of the typical solid/multicystic ameloblastoma.solid/multicystic ameloblastoma.

The ameloblastic carcinoma shows The ameloblastic carcinoma shows cytological features of malignancy in cytological features of malignancy in addition to a pattern of an addition to a pattern of an ameloblastoma.ameloblastoma.


Treatment & PrognosisTreatment & Prognosis Long-term follow-up does not permit Long-term follow-up does not permit

accurate assumptions to be made accurate assumptions to be made but prognosis appears to be poor.but prognosis appears to be poor.

Approximately 50 % of the patients Approximately 50 % of the patients with documented metastases and with documented metastases and long-term follow-up have died as the long-term follow-up have died as the result of their disease.result of their disease.

Adenomatoid Odontogenic Adenomatoid Odontogenic Tumor (AOT)Tumor (AOT)

Formerly called an Formerly called an adenoameloblastoma, a somewhat adenoameloblastoma, a somewhat deceptive term that should be deceptive term that should be discarded, the AOT represents about discarded, the AOT represents about 3-7 % of all odontogenic tumors.3-7 % of all odontogenic tumors.

This epithelial tumor has an This epithelial tumor has an inductive effect on the odontogenic inductive effect on the odontogenic ectomesenchyme with dentinoid ectomesenchyme with dentinoid frequently being produced.frequently being produced.

AOT: Clinical FeaturesAOT: Clinical Features Patient Age: The peak age is in the Patient Age: The peak age is in the

second decade with a mean around 17 second decade with a mean around 17 years.years.

Gender Predilection: Females, 2:1.Gender Predilection: Females, 2:1. Location: Sixty-five percent of the AOTs Location: Sixty-five percent of the AOTs

occur in the maxilla with 65 % occurring occur in the maxilla with 65 % occurring in the canine region. Seventy-five in the canine region. Seventy-five percent of the cases are associated with percent of the cases are associated with the crown of an unerupted tooth. On the crown of an unerupted tooth. On rare occasion the lesion is extraosseous.rare occasion the lesion is extraosseous.

AOT: Radiographic and AOT: Radiographic and Additional FeaturesAdditional Features

AOTs typically appear as pericoronal AOTs typically appear as pericoronal radiolucencies, which may have radiolucencies, which may have radiopaque material (“snowflake” radiopaque material (“snowflake” calcifications) within the lucency.calcifications) within the lucency.

These lesions are frequently asymptomatic These lesions are frequently asymptomatic and therefore are discovered upon routine and therefore are discovered upon routine radiographic examination. AOTs may also radiographic examination. AOTs may also block the eruption of a permanent tooth block the eruption of a permanent tooth and be discovered when radiographs are and be discovered when radiographs are taken to “search for” the unerupted tooth.taken to “search for” the unerupted tooth.

AOT: Histologic AOT: Histologic FeaturesFeatures

The lesion is usually surrounded by a thick, The lesion is usually surrounded by a thick, fibrous capsule. fibrous capsule.

The tumor is composed of spindle-shaped The tumor is composed of spindle-shaped epithelial cells that form sheets, strands or epithelial cells that form sheets, strands or whorled masses with little connective tissue.whorled masses with little connective tissue.

The epithelial cells may form rosette-like The epithelial cells may form rosette-like structures, tubular or duct-like structures structures, tubular or duct-like structures may be prominent or absent. may be prominent or absent.

Calcifications may be observed in the tumor Calcifications may be observed in the tumor mass.mass.

AOT: Treatment and AOT: Treatment and PrognosisPrognosis

Enucleation is the treatment of Enucleation is the treatment of choice as the tumor is easily choice as the tumor is easily removed from the bone.removed from the bone.

AOTs seldom recur.AOTs seldom recur.

Calcifying Epithelial Calcifying Epithelial Odontogenic Tumor (CEOT; Odontogenic Tumor (CEOT;

Pindborg Tumor)Pindborg Tumor) Pindborg tumor accounts for < 1 % Pindborg tumor accounts for < 1 %

of all odontogenic tumors.of all odontogenic tumors. It is clearly of odontogenic origin but It is clearly of odontogenic origin but

its histogenesis is uncertain.its histogenesis is uncertain. The tumor cells are said to resemble The tumor cells are said to resemble

cells of the stratum intermedium.cells of the stratum intermedium.

CEOT: Clinical FeaturesCEOT: Clinical Features

Patient Age: Patients ages range from Patient Age: Patients ages range from the second to the tenth decades with the second to the tenth decades with a mean around 40 years.a mean around 40 years.

Gender Predilection: There is no Gender Predilection: There is no reported sex predilection.reported sex predilection.

Location: 75 % of the CEOTs occur in Location: 75 % of the CEOTs occur in the mandible with most occurring in the mandible with most occurring in the posterior region. A rare the posterior region. A rare peripheral CEOT does occur. peripheral CEOT does occur.

CEOT: Radiographic CEOT: Radiographic FeaturesFeatures

CEOTs occur as radiolucent lesions CEOTs occur as radiolucent lesions with/without opaque foci.with/without opaque foci.

They are usually well-circumscribed They are usually well-circumscribed and may be unilocular or and may be unilocular or multilocular.multilocular.

Slightly over 50 % of the CEOTs are Slightly over 50 % of the CEOTs are associated with an unerupted tooth. associated with an unerupted tooth.

CEOT: Histologic CEOT: Histologic FeaturesFeatures

This lesion is typically composed of islands, sheets This lesion is typically composed of islands, sheets or strands of polyhedral epithelial cells in a or strands of polyhedral epithelial cells in a fibrous stroma.fibrous stroma.

Areas of amorphous, eosinophilic, hyalinized Areas of amorphous, eosinophilic, hyalinized extracellular material may be scattered extracellular material may be scattered throughout.throughout.

Cells outlines are distinct and intercellular Cells outlines are distinct and intercellular bridges may be seen.bridges may be seen.

Nuclei show considerable variation with giant Nuclei show considerable variation with giant nuclei and pleomorphism observed.nuclei and pleomorphism observed.

Calcifications may be noted as well as amyloid-Calcifications may be noted as well as amyloid-like material. Liesegang rings also may be like material. Liesegang rings also may be present.present.

CEOT: Additional Features, CEOT: Additional Features, Treatment and PrognosisTreatment and Prognosis

Bony lesions most commonly present as Bony lesions most commonly present as painless, slow-growing swellings.painless, slow-growing swellings.

Peripheral lesions typically appear as non-Peripheral lesions typically appear as non-specific sessile gingival masses.specific sessile gingival masses.

Conservative local resection is the treatment Conservative local resection is the treatment of choice as these lesions are typically less of choice as these lesions are typically less aggressive than the ameloblastoma.aggressive than the ameloblastoma.

With this treatment the recurrence rate is With this treatment the recurrence rate is approximately 15 % and the overall approximately 15 % and the overall prognosis is good.prognosis is good.

Squamous Odontogenic Squamous Odontogenic Tumor (SOT): Clinical Tumor (SOT): Clinical

FeaturesFeatures Patient Age: Second through the Patient Age: Second through the

seventh decades (mean 40 years).seventh decades (mean 40 years). Gender Predilection: NoneGender Predilection: None Location: SOTs occur with about Location: SOTs occur with about

equal frequency in maxilla and equal frequency in maxilla and mandible. They are more common mandible. They are more common in the anterior regions of the jaws in the anterior regions of the jaws than in the posterior. The lesions than in the posterior. The lesions occur in the alveolar process. occur in the alveolar process.

SOT: Radiographic and SOT: Radiographic and Histologic FeaturesHistologic Features

SOTs appear as non-specific radiolucent SOTs appear as non-specific radiolucent lesions. They may be well-circumscribed lesions. They may be well-circumscribed or ill-defined. They often appear or ill-defined. They often appear triangular in shape and lateral to the triangular in shape and lateral to the tooth root.tooth root.

Histologically, they appear as islands of Histologically, they appear as islands of bland-appearing squamous epithelium in bland-appearing squamous epithelium in a mature fibrous connective tissue a mature fibrous connective tissue stroma. The peripheral cells do not stroma. The peripheral cells do not show the characteristic polarization seen show the characteristic polarization seen in the ameloblastoma.in the ameloblastoma.

SOT: Additional Features, SOT: Additional Features, Treatment and PrognosisTreatment and Prognosis

SOTs often present as painless SOTs often present as painless gingival swellings associated with gingival swellings associated with tooth mobility. Approximately 25 % tooth mobility. Approximately 25 % are asymptomatic.are asymptomatic.

Conservative local excision or Conservative local excision or curettage appears to be effective curettage appears to be effective treatment and there have only be a treatment and there have only be a few recurrences reported.few recurrences reported.

Mixed Mixed Odontogenic Odontogenic

TumorsTumorsThis group of tumors is composed This group of tumors is composed

of proliferating odontogenic of proliferating odontogenic epithelium in a cellular epithelium in a cellular

ectomesenchyme resembling the ectomesenchyme resembling the dental papilla.dental papilla.

Ameloblastic Fibroma: Ameloblastic Fibroma: Clinical FeaturesClinical Features

This true mixed odontogenic tumor This true mixed odontogenic tumor is more common in patients in the is more common in patients in the first and second decades of life with first and second decades of life with a mean of 14 years.a mean of 14 years.

It is slightly more common in males It is slightly more common in males than females.than females.

Approximately 70 % of the Approximately 70 % of the ameloblastic fibromas occur in the ameloblastic fibromas occur in the posterior mandible.posterior mandible.

Ameloblastic Fibroma: Ameloblastic Fibroma: Radiographic FeaturesRadiographic Features

Generally, these lesions appear as Generally, these lesions appear as either a unilocular or multilocular either a unilocular or multilocular radiolucency.radiolucency.

They tend to be well-defined and They tend to be well-defined and may have a sclerotic border. may have a sclerotic border.

Approximately, 50 % are associated Approximately, 50 % are associated with an unerupted tooth.with an unerupted tooth.

Ameloblastic Fibroma: Ameloblastic Fibroma: Histologic FeaturesHistologic Features

The tumor is composed of a cell-rich The tumor is composed of a cell-rich mesenchymal tissue resembling the mesenchymal tissue resembling the primitive dental papilla admixed primitive dental papilla admixed with proliferating odontogenic with proliferating odontogenic epithelium.epithelium.

Ameloblastic Fibroma: Ameloblastic Fibroma: Additional Features, Additional Features,

Treatment and PrognosisTreatment and Prognosis The tumor is often encapsulated with The tumor is often encapsulated with

small tumors usually being small tumors usually being asymptomatic. Larger tumors produce asymptomatic. Larger tumors produce swelling, which can expand the cortex swelling, which can expand the cortex and be quite pronounced.and be quite pronounced.

Most ameloblastic fibromas are treated Most ameloblastic fibromas are treated by conservative surgical excision; by conservative surgical excision; however, a 20 % recurrence rate has led however, a 20 % recurrence rate has led some surgeons to recommend a more some surgeons to recommend a more aggressive approach.aggressive approach.

Ameloblastic Fibro-Ameloblastic Fibro-odontomaodontoma

This lesion is defined as a tumor with This lesion is defined as a tumor with general features of an ameloblastic general features of an ameloblastic fibroma but containing enamel and fibroma but containing enamel and dentin.dentin.

Some investigators believe that this Some investigators believe that this entity is but a stage in the entity is but a stage in the development of an odontoma; however, development of an odontoma; however, most agree that progressive most agree that progressive destructive tumors are true neoplasms.destructive tumors are true neoplasms.

Ameloblastic Fibro-Ameloblastic Fibro-odontoma: Clinical and odontoma: Clinical and Radiographic FeaturesRadiographic Features

Patient Age: Most common in the 5-12 Patient Age: Most common in the 5-12 year age range with a mean of 10 years.year age range with a mean of 10 years.

Gender Predilection: None.Gender Predilection: None. Location: It is more common in the Location: It is more common in the

premolar/molar regions of both jaws.premolar/molar regions of both jaws. Radiographic Features: Usually appears Radiographic Features: Usually appears

as a well-defined unilocular or rarely as a well-defined unilocular or rarely multilocular radiolucency with variable multilocular radiolucency with variable amounts of calcified material which is amounts of calcified material which is radiopaque. Therefore, it may appear as a radiopaque. Therefore, it may appear as a mixed, radiolucent-radiopaque lesion.mixed, radiolucent-radiopaque lesion.

Ameloblastic Fibro-Ameloblastic Fibro-odontoma: Histologic odontoma: Histologic

FeaturesFeatures The soft tissue component is The soft tissue component is

identical to the ameloblastic identical to the ameloblastic fibroma. The calcified portion fibroma. The calcified portion consists of foci of enamel and dentin consists of foci of enamel and dentin matrix formation in close matrix formation in close relationship to the epithelial relationship to the epithelial structures.structures.

Ameloblastic Fibro-Ameloblastic Fibro-odontoma: Treatment and odontoma: Treatment and

PrognosisPrognosis The ameloblastic fibro-odontoma is The ameloblastic fibro-odontoma is

usually treated by conservative usually treated by conservative curettage with the lesion separating curettage with the lesion separating easily from the surrounding bone. easily from the surrounding bone.

Prognosis is excellent and Prognosis is excellent and recurrence is unusual.recurrence is unusual.

Ameloblastic Ameloblastic FibrosarcomaFibrosarcoma

This lesion is considered the This lesion is considered the malignant counterpart of the malignant counterpart of the ameloblastic fibroma in which the ameloblastic fibroma in which the mesenchymal portion shows features mesenchymal portion shows features of malignancy.of malignancy.

The ameloblastic fibrosarcoma may The ameloblastic fibrosarcoma may arise de novo or there may be a arise de novo or there may be a malignant transformation of an malignant transformation of an ameloblastic fibroma.ameloblastic fibroma.

Ameloblastic Fibrosarcoma: Ameloblastic Fibrosarcoma: Clinical and Radiographic Clinical and Radiographic

FeaturesFeatures Patient Age: The mean age for Patient Age: The mean age for

patients with ameloblastic patients with ameloblastic fibrosarcoma is 26 years.fibrosarcoma is 26 years.

Gender Predilection: Males 2:1.Gender Predilection: Males 2:1. Location: 75 % have occurred in the Location: 75 % have occurred in the

mandible.mandible. Radiographic Features: Appear as an Radiographic Features: Appear as an

ill-defined, destructive, radiolucent ill-defined, destructive, radiolucent lesion.lesion.

Ameloblastic Fibrosarcoma: Ameloblastic Fibrosarcoma: Histologic Features Histologic Features

The epithelial component of this The epithelial component of this tumor appears histologically benign.tumor appears histologically benign.

The mesenchymal portion is highly The mesenchymal portion is highly cellular. The cells are cellular. The cells are hyperchromatic and quite hyperchromatic and quite pleomorphic. Mitoses are usually pleomorphic. Mitoses are usually prominent.prominent.

Ameloblastic Fibrosarcoma: Ameloblastic Fibrosarcoma: Additional Features, Additional Features,

Treatment & PrognosisTreatment & Prognosis Pain and swelling are typically Pain and swelling are typically

associated with this tumor. Rapid associated with this tumor. Rapid clinical growth is another common clinical growth is another common feature.feature.

Radical surgical excision is the Radical surgical excision is the treatment of choice.treatment of choice.

The long-term prognosis is difficult The long-term prognosis is difficult to ascertain because of the small to ascertain because of the small number of reported cases.number of reported cases.

OdontomaOdontoma

The odontoma is the most common The odontoma is the most common odontogenic tumor.odontogenic tumor.

It is not a true neoplasm but rather is It is not a true neoplasm but rather is considered to be a developmental anomaly considered to be a developmental anomaly (hamartoma).(hamartoma).

Two types of odontomas are recognized:Two types of odontomas are recognized: Compound: this type of odontoma is composed of Compound: this type of odontoma is composed of

multiple small tooth-like structures.multiple small tooth-like structures. Complex: this lesion is composed of a Complex: this lesion is composed of a

conglomerate mass of enamel and dentin, which conglomerate mass of enamel and dentin, which bears no anatomic resemblance to a tooth.bears no anatomic resemblance to a tooth.

Odontoma: Clinical Odontoma: Clinical FeaturesFeatures

Patient Age: Most cases are Patient Age: Most cases are recognized during the second decade recognized during the second decade of life with a mean of 14 years.of life with a mean of 14 years.

Gender Predilection: Approximately Gender Predilection: Approximately equal.equal.

Location: Somewhat more common in Location: Somewhat more common in the maxilla. The compound type is the maxilla. The compound type is more often in the anterior maxilla while more often in the anterior maxilla while the complex type occurs more often in the complex type occurs more often in the posterior regions of either jaw.the posterior regions of either jaw.

Odontoma: Radiographic Odontoma: Radiographic FeaturesFeatures

Early lesions are radiolucent with Early lesions are radiolucent with smooth, well-defined contours. smooth, well-defined contours.

Later a well-defined radiopaque Later a well-defined radiopaque appearance develops.appearance develops.

The compound type shows apparent The compound type shows apparent tooth shapes while the complex type tooth shapes while the complex type appears as a uniform opaque mass appears as a uniform opaque mass with no apparent tooth shapes with no apparent tooth shapes present.present.

Odontoma: Additional Odontoma: Additional FeaturesFeatures

Most odontomas are small and do not exceed Most odontomas are small and do not exceed the size of a normal tooth in the region.the size of a normal tooth in the region.

However, large ones do occur and these may However, large ones do occur and these may cause expansion of the jaw.cause expansion of the jaw.

Most odontomas are asymptomatic and as a Most odontomas are asymptomatic and as a result are discovered upon routine result are discovered upon routine radiographic examination.radiographic examination.

Odontomas may block the eruption of a Odontomas may block the eruption of a permanent tooth and in these cases are often permanent tooth and in these cases are often discovered when “searching for” the “missing” discovered when “searching for” the “missing” tooth radiographically.tooth radiographically.

Odontoma: Histologic Odontoma: Histologic FeaturesFeatures

The compound odontoma is composed The compound odontoma is composed of enamel, dentin and cementum of enamel, dentin and cementum arrange in recognizable tooth forms; arrange in recognizable tooth forms; some enamel matrix may be retained in some enamel matrix may be retained in immature and hypomineralized immature and hypomineralized specimens.specimens.

The complex odontoma is composed of The complex odontoma is composed of enamel, dentin and cementum but these enamel, dentin and cementum but these tissues are arranged in a random tissues are arranged in a random manner that bears no morphological manner that bears no morphological resemblance to a tooth.resemblance to a tooth.

Odontoma: Treatment and Odontoma: Treatment and PrognosisPrognosis

Odontomas are treated by simple Odontomas are treated by simple local excision and the prognosis is local excision and the prognosis is excellent.excellent.

Tumors of Tumors of Odontogenic Odontogenic

EctomesenchymeEctomesenchyme

(Central) Odontogenic (Central) Odontogenic Fibroma: Clinical FeaturesFibroma: Clinical Features

Fewer than 50 cases have been reported in Fewer than 50 cases have been reported in the English literature.the English literature.

Patient Age: Patients have ranged in age Patient Age: Patients have ranged in age from 9-80 years old with a mean of 40 years.from 9-80 years old with a mean of 40 years.

Gender Predilection: Females, 7.4:1 in one Gender Predilection: Females, 7.4:1 in one study.study.

Location: Sixty percent occur in the maxilla Location: Sixty percent occur in the maxilla where most are located anterior to the first where most are located anterior to the first molar. When in the mandible, approximately molar. When in the mandible, approximately 50 % occur in the posterior jaw.50 % occur in the posterior jaw.

Odontogenic Fibroma: Odontogenic Fibroma: Radiographic AppearanceRadiographic Appearance

The odontogenic fibroma usually The odontogenic fibroma usually appears as a well-defined, unilocular appears as a well-defined, unilocular radiolucency. It is often associated radiolucency. It is often associated with the apical area of an erupted with the apical area of an erupted tooth.tooth.

Larger lesions are often multilocular.Larger lesions are often multilocular. Many odontogenic fibromas have Many odontogenic fibromas have

sclerotic borders.sclerotic borders. Root resorption is common.Root resorption is common.

Odontogenic Fibroma: Odontogenic Fibroma: Additional FeaturesAdditional Features

Small odontogenic fibromas are Small odontogenic fibromas are usually asymptomatic.usually asymptomatic.

The larger lesions may be associated The larger lesions may be associated with localized bony expansion of the with localized bony expansion of the jaw or with the loosening of adjacent jaw or with the loosening of adjacent teeth.teeth.

Odontogenic Fibroma: Odontogenic Fibroma: Histologic FeaturesHistologic Features

Some authors have described two Some authors have described two separate types of odontogenic fibromas.separate types of odontogenic fibromas.

The The simple odontogenic fibromasimple odontogenic fibroma is is composed of stellate fibroblasts arranged composed of stellate fibroblasts arranged in a whorled pattern with fine collagen in a whorled pattern with fine collagen fibrils and a lot of ground substance. fibrils and a lot of ground substance.

Foci of odontogenic epithelium may or Foci of odontogenic epithelium may or may not be present. may not be present.

Occasionally, foci of dystrophic Occasionally, foci of dystrophic calcification may be present.calcification may be present.

Odontogenic Fibroma: Odontogenic Fibroma: Histologic FeaturesHistologic Features

The The WHO type odontogenic fibromaWHO type odontogenic fibroma appears as a fairly cellular fibrous appears as a fairly cellular fibrous connective tissue with collagen fibers connective tissue with collagen fibers arranged in interlacing bundles. arranged in interlacing bundles.

Odontogenic epithelium in the form of Odontogenic epithelium in the form of long strands or isolated nests is long strands or isolated nests is present throughout the lesion. present throughout the lesion.

Calcifications composed of cementoid Calcifications composed of cementoid and/or dentinoid may be present.and/or dentinoid may be present.

Odontogenic Fibroma: Odontogenic Fibroma: Treatment and PrognosisTreatment and Prognosis

The odontogenic fibroma is usually The odontogenic fibroma is usually treated by enucleation and treated by enucleation and curettage.curettage.

There have been few recurrences, There have been few recurrences, this the prognosis is good.this the prognosis is good.

Odontogenic Myxoma: Odontogenic Myxoma: Clinical and Radiographic Clinical and Radiographic

FeaturesFeatures Patient Age: 10-50 years with a mean Patient Age: 10-50 years with a mean

around 30 years.around 30 years. Gender Predilection: Reported to be Gender Predilection: Reported to be

about equal.about equal. Location: May occur in any area of the Location: May occur in any area of the

jaws but more common in the mandible.jaws but more common in the mandible. Radiographic Appearance: Radiolucent Radiographic Appearance: Radiolucent

lesion often with a multilocular lesion often with a multilocular appearance. The borders may be appearance. The borders may be indistinct.indistinct.

Odontogenic Myxoma: Odontogenic Myxoma: Histologic FeaturesHistologic Features

The tumor is composed of loosely The tumor is composed of loosely arranged stellate, spindle-shaped and arranged stellate, spindle-shaped and round cells in an abundant, loose myxoid round cells in an abundant, loose myxoid stroma with few collagen bundles.stroma with few collagen bundles.

Epithelial cells are not required for Epithelial cells are not required for diagnosis.diagnosis.

The odontogenic myxoma may be The odontogenic myxoma may be confused with a chrondromyxoid fibroma confused with a chrondromyxoid fibroma or with myxoid change in an enlarged or with myxoid change in an enlarged dental follicle or papilla.dental follicle or papilla.

Odontogenic Myxoma: Odontogenic Myxoma: Treatment and PrognosisTreatment and Prognosis

Small odontogenic myxomas are treated Small odontogenic myxomas are treated by curettage, while larger lesions may by curettage, while larger lesions may require surgical resection.require surgical resection.

Odontogenic myxomas are not Odontogenic myxomas are not encapsulated and tend to infiltrate encapsulated and tend to infiltrate adjacent tissues.adjacent tissues.

Recurrence rates of up to 25 % are Recurrence rates of up to 25 % are reported.reported.

Overall, the prognosis is good for most Overall, the prognosis is good for most odontogenic myxomas.odontogenic myxomas.

09 Odont Tumor

Documents

common odontogenic tumor

mixed odontogenic tumors

ameloblastoma ameloblastomas

benign tumor

lining of odontogenic

granular cell type

cases solid

histologic features