Benign Odontogenic Tumors Dr. T Flashcards
What is the relationship between lesion’s agrressivness, rate of reccurance and follow up duration ?
the more aggressive the biologic behavior, the higher risk of
recurrence, and the longer the follow up needed for the patient
What is the spectrum of benign and malignant lesions
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Which lesions are considered benigns
Things that have a very low rate of recurrence when you do a conservative excision or a nucleation ►they’re going to be very benign and they’re not going to be likely to be recurrent:
▪ Odontoma and radicular cysts are way down here near the benign side
▪ AOT (Adenomatoid Odontogenic Tumor) is benign.
▪ COCs (Calcifying odontogenic cyst) are benign.
▪ OKCs (Odontogenic keratocyst) ‐ they’re benign.
▪ Even Ameloblastomas are benign
which lesions are on the malignant side?
But eventually you get over to the side over here where you can have something like an Ameloblastic carcinoma ‐ truly malignant –> We know that it can metastasize and it can lead to death
▪ Lesions like Ameloblastomas and CEOTs will need to be managed more aggressively. (Not just curettage, aka surgical scraping or cleaning)
o You have a resection ‐ either a portion of the mandible is
removed or a segment of the mandible is removed.
What are the 3 Classification of
benign tumors?
- Epithelial
- Mesenchymal
- Mixed
What are the list of Epithelial Benign Tumors?
(5)
▪ Ameloblastoma
▪ Adenomatoid odontogenic tumor
▪ Calcifying epithelial odontogenic tumor
▪ Squamous odontogenic tumor
▪ Odontogenic keratocyst (aka Keratocystic odontogenic tumor)
What are the list of Mesenchymal Benign Tumors?
(5)
▪ Odontogenic myxoma
▪ Central Odontogenic fibroma
▪ Cementifying fibroma
▪ Cementoblastoma
▪ Granular cell odontogenic tumor
What are the list of Mixed Benign tumors?
5
▪ Odontoma (complex and compound)
▪ Ameloblastic fibroma/odontoma
▪ Primordial odontogenic tumor
▪ Dentinogenic ghost cell tumor
▪ Calcifying cystic odontogenic tumor(aka COC, ghost cell tumor)
Ameloblastoma
Charcterstics
- An epithelial odontogenic neoplasm (Tumor of Epithelial Origin)
- with a close histologic resemblance to the enamel organ
Ameloblastoma
Origin
Potential sources of epithelium include:
o Enamel organ – look like they’re about to deposit a
substance but never do
o Odontogenic rests (Malassez, Serres)
o Reduced enamel epithelium
o Epithelial lining of odontogenic cysts ‐ can actually have an ameloblastoma arise within a dentigerous cyst
Ameloblastoma
Radiographically
-Osteolytic tumor (radiolucent – no hard tissue formed)
- Well-circumscribed uni- or multilocular radiolucency
- Often with sclerotic or corticated borders
- May see blunt root resorption and displacement of teeth
- Frequently seen in association with unerupted teeth
Ameloblastoma
Clinically
- Rather slow growing tumor
- Larger lesions present as painless expansion or swelling of bone
- Smaller ones are asymptomatic, can be seen on routine imaging
- Buccal and lingual cortical expansion is common
- May perforate cortical plate and invade surrounding soft tissue
- Can arise in a dentigerous cyst (see transition from stratified
- squamous to ameloblastic epithelium)
Ameloblastoma
Demographics
▪ 11‐18% of non‐cystic lesions of the maxillofacial bones
▪ 4th and 5th decade most common, but occurs over a broad age range (rare in first decade)
o Usually starts 2nd decade, can go up to 80‐90s. Late 30s/early 40s are usually the peak
▪ > 80% occur in the mandible (most in molar/ramus area)
ameloblastoma
location
▪ Almost 80% or a little over 80% (of ameloblasts) are down in the mandible.
▪ And the vast majority are in the posterior mandible
▪ Do occur in maxilla but at lower rate
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Ameloblastoma
Etiology
▪ Over expression of Bcl‐2 (anti‐apoptotic protein)
▪ Expression of fibroblast growth factor (FGF)
▪ Over expression of matrix metalloproteinases (MMPs 9 and 20) – like in OKC, allowing tumor to grow into surrounding area
▪ Surprisingly, no significant increase in Ki‐67 expression (cell
proliferation marker) – ameloblastomas do NOT turn over rapidly
What is
the second most common
odontogenic neoplasm?
Ameloblastoma
(after odontoma)
o although odontomas are more like hamartomas
Which tumor can arise in a dentigerous cyst?
Ameloblastoma
(we see transition from stratified squamous to ameloblastic epithelium)
Ameloblastoma
Types
Conventional/multicystic/solid/ (~ 80%)
- Unicystic (~6-15%) need entire specimen (excision) to know
- Desmoplastic
- Peripheral
- Malignant
What is this radiographic finding?
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Unilocular and unicystic ‐ An example of a unilocular ameloblastoma that is
not associated with an impacted tooth
▪ Is between roots of two teeth, may be confused with lateral
periodontal cyst. Well‐circumscribed radiolucency
What is this radiographic finding?
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▪ Typical appearance for ameloblastoma
Multilocular, very well‐circumscribed, associated with impacted tooth.
Can see bowing of inferior aspect of mandible
lateral oblique radiograph.was used here
What is this radiographic & clinical finding?
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Ameloblastoma
clinically: Have expansion of the buccal plate, obliterating the vestibule in this area.
Radiographically: Root resorption of molar, unilocular radiolucency in mandible
What is this radiographic finding?
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Ameloblastoma
- Small lesion distal to impacted tooth.
- Unilocular radiolucency with elevation of alveolar ridge + some expansion of soft tissue
What is this radiographic finding?
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Ameloblastoma
▪ Well‐circumscribed radiolucency with a sclerotic or
corticated margin.
▪ If you had a CBCT, it would probably show you that there
was a thin septa in this area of residual bone trabeculae.
▪ Fracture could be caused by very large cysts.
▪ Resolve by decompressing unless with odontogenic tumor – need to remove the mandible 1cm+ on either side of lesion
Conventional/Solid Ameloblastoma
Treatment
- Resection (treatment depends on extent of the lesion and anatomy of involved bone)
- Segmental
- Composite
- Long term (decades) follow up is needed for these patients
Case
16yo female
Describe the lesion and what is the diagnosis?
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▪Left mandible, multilocular radiolucency associated with impacted tooth
▪ It’s well circumscribed, edge may be a little bit sclerotic or corticated
▪ It has displaced an impacted tooth down towards the inferior
aspect of the mandible
▪ Appears to be expanding the cortex of the mandible in areas
▪ There’s blunt resorption of the teeth adjacent (PMs and molar)
Ameloblastoma
Case
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▪ Well‐circumscribed radiolucency, no impacted tooth
▪ But notice that it’s coming up to posterior aspect of first molar
▪ Surgery done to remove lesion, left inferior aspect of mandible
Follow‐up image: conservative surgery but still removed bone up to mesial aspect. Less conservative would be removing entire mandible
▪ Concern with that is paresthesia (from removing the nerve as well)
Conventional/Solid Ameloblastoma
Unicystic
ameloblastoma
types
Subgroup of
ameloblastomas
▪ Unicystic (Simple or luminal)
- lumina- confined to the surface lining of the cystic space
▪ Plexiform (intraluminal)
- intralumina-one or more areas of the ameloblastic epithelial lining, proliferate into the lumen of the cystic space
▪ Mural – hard to distinguish from conventional,
so pathologists think they should NOT be treated the same as unicystic (which would be a more conservative treatment)
▪ Ameloblastoma arising in a cyst ‐ can usually be treated in a similar way as unicystic ameloblastoma.
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Unicystic Ameloblastoma
Demographcics and Locations
▪ Younger initial presentation (~ 50% in 2nd decade)
▪ 90% in MD (mandibular)
▪ Typically asymptomatic and found on routine radiographic exam
Unicystic Ameloblastoma
Radiographically
- Commonly a well‐circumscribed radiolucency that surrounds the crown of an unerupted tooth
- Commonly accompanied by root resoprtion
Unicystic Ameloblastoma
radiographically can be confused with which cyst?
- Radiographically can be confused with dentigerous cyst
- Presence of root resorption should increase your suspicion of ameloblastoma
What is this radiographic finding?
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Unicystic Ameloblastoma
but could be
Dentigerous Cyst
based on clinical presentation!
So radiograph is not diagonstic
Unicystic Ameloblastoma
Treatment
- Treatment is typically enucleation and curettage
- Reports of lower rate of recurrence (10‐20%) than conventional ameloblastoma (50‐90%) with similar treatment
- Some recommend decompression prior to surgery
- Use of Carnoy’s solution after enucleation- resulted in a recurrence rate lower
Desmoplastic
Ameloblastoma
Location
- Anterior jaws (particularly maxilla)
Desmoplastic
Ameloblastoma
Radiographically
- looks “fibro‐osseous” due to mixed radiolucentradiopaque appearance
- Mineralization of dense collagen
- Well‐circumscribed, corticated.
What is this radiographic finding?
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Desmoplastic
Ameloblastoma
- Spherical growth. Within it, has both radiodense and radiolucent areas (is
- mixed radiolucent‐radiopaque)– similar appearance to benign fibro‐osseous lesions.
- Well‐circumscribed, corticated.
Peripheral
Ameloblastoma
Origin and Charcterstics
- Thought to arise from epithelial rests or basal cells in the gingiva
- Uncommon
- Does not invade underlying bone
- Histology is the same as conventional type
Peripheral
Ameloblastoma
location
- Found on gingiva or alveolar mucosa (*that’s why it’s named peripheral or extraosseous)
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Peripheral
Ameloblastoma
What are the two types of “Malignant”
Ameloblastomas ?
- Malignant ameloblastoma
- Ameloblastic carcinoma
What is a malignant ameloblastoma?
▪ Malignant ameloblastoma
o Primary lesion and metastasis have normal welldifferentiated
ameloblastic (benign) histology
o Most commonly to lung
What is Ameloblastic carcinoma?
- a primary lesion has atypical poorly‐differentiated
- neoplastic(malignant) histology
- may metastasize
CALCIFYING EPITHELIAL ODONTOGENIC TUMOR
CEOT
also known as ?
Pindborg Tumor
Calcifying Epithelial Odontogenic Tumor
(CEOT)
▪ Uncommon (~1% of odontogenic tumors)
▪ Does not have inductive effect
Calcifying Epithelial Odontogenic Tumor
(CEOT)
Demographics and Location
o 2nd to 10th decades, peak ~ 4th decade
o MD (mandibular) 2 : 1 MX (maxillary)
o Usually posterior mandible
Calcifying Epithelial Odontogenic Tumor
(CEOT)
Clinically
- Presents as painless slowly expanding swellings
- sessile swellings of the gingiva or alveolus ( 2 times more on mandible than maxilla
- Peripheral lesion may be seen, but are rare
Calcifying Epithelial Odontogenic Tumor
(CEOT)
Radiographically
- May be unilocular, but most commonly as a multilocular lesion
- May be entirely radiolucent or a mixed radiolucent-radiopaque lesion
-
Often associated with an unerupted tooth
- MD third molar most common
- Calcifications in the lesion, if present, are typically prominent around the crown of the impacted tooth.
Calcifying Epithelial Odontogenic Tumor
(CEOT) have clinical presentation similar to what lesion?
- CEOT clinically is similar to ameloblastoma
- Also, CEOT has potential to be locally invasive, if in the right anatomic location, but has a less aggressive biologic behavior compared to ameloblastoma
Calcifying Epithelial Odontogenic Tumor
(CEOT)
Treatment
▪ Enucleation _with peripheral ostectom_y
▪ Resection with rim of normal bone
▪ Recurrence rate is ~12%
▪ ~ 2% demonstrate malignant transformation
case
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Calcifying Epithelial Odontogenic Tumor
(CEOT)
Clinically: we see a little expansion on inferior aspect of mandible + lingual too
Radiographically: we see well‐circumscribed, a little corticated/sclerotic edge, impacted tooth
▪ we can see bowing of inferior aspect of mandible
▪ Within areas of radiolucency, see areas of opacity (calcified lesions = classic CEOT)
▪ When smaller► could have looked *unilocular*
What is this radiographic finding?
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Calcifying Epithelial Odontogenic Tumor(CEOT)
- flecks of calcifications.
- Calcifications all around crown is common
What is this radiographic finding?
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Calcifying Epithelial Odontogenic Tumor(CEOT)
- Multilocular radiolucency with calcifications.
- an expansion up to PMs and back to 2nd molar
- as well as bowing of mandible.
What is this radiographic finding?
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Calcifying Epithelial Odontogenic Tumor(CEOT)
- Fewer calcifications here, well‐circumscribed and corticated, impacted tooth.
- periosteal reaction causing elevation at the bottom of image!
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Calcifying Epithelial Odontogenic Tumor(CEOT)
- well‐circumscribed radiolucency with calcifications in lower anteriors
Adenomatoid odontogenic tumor
(AOT)
Demographics and Location
▪ 2/3 anterior jaws
▪ 2/3 females
▪ 2/3 associated with an impacted canine
▪ 2/3 MX
▪ 2/3 2nd decade – kids and teenagers\
That’s why it’s known as the tumor of two thirds
▪ ~ 3‐7% of all odontogenic tumors
New research showing more in _ant md_ though
Adenomatoid odontogenic tumor
(AOT)
Clinical charcterstics
- Frequently asymptomatic, discovered upon routine radiographic exam or when lesion becomes large enough to expand bone
- Tumor of Epithelial Origin
Adenomatoid odontogenic tumor
(AOT)
Origin
- thought to arise from remnants of the dental lamina in the gubernacular cord /canal
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Adenomatoid odontogenic tumor
(AOT)
Radiographically
▪ ~ 75% are well‐circumscribed unilocular radiolucency involving the crown of an unerupted tooth
o less often, they are found between the roots of teeth
▪ Mixed radiolucent/radiopaque appearance is likened to “snowflake” calcifications
▪ May be totally radiopaque in some cases
▪ Divergence of roots is frequently seen
If an Adenomatoid odontogenic tumor (AOT) is not showing any calcifications yet, it’s in the differential
diagnosis with —— ?
a dentigerous cyst.
Adenomatoid odontogenic tumor
(AOT)
Treatment
- Treatment is usually enucleation
- recurrence is rare
What is the DD?
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well‐circumscribed radiolucency at crown of an impacted canine
Hard to tell if attaches at CEJ.
If further down, less likely a dentigerous cyst and more likely AOT, ameloblastoma, or OKC
What is this radiographic finding?
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we see calcifications forming, with both radiolucent and radiolucent areas.
▪ Dentingerous cyst, ameloblastoma, and OKC are NO LONGER in the differential diagnosis.
This is clearly AOT
_(_Adenomatoid odontogenic tumor)
What is this clinical finding?
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Adenomatoid odontogenic tumor
(AOT)
Swelling in maxillary vestibule
What is this clinical finding?
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Adenomatoid odontogenic tumor
(AOT)
fibrous capsule of AOT is at least partially encapsulated.
Easy to remove; “popped right out”.
What is this clinical finding?
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Adenomatoid odontogenic tumor
(AOT)
An expansion into lingual area as well as into vestibule
What is this radiographic finding?
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Adenomatoid odontogenic tumor
(AOT)
Snowflake‐like calcifications within mixed, well‐circumscribed radiolucency
What is this radiographic finding?
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Adenomatoid odontogenic tumor
(AOT)
- Teardrop shape / inverted pear between roots of teeth.
- Well-circumscribed, corticated margin & snowflake‐like calcifications within
Squamous Odontogenic Tumor
(SOT)
Demographics and Location
▪ Typically involves alveolar ridge
▪ Anterior > Posterior jaws
▪ Seen from 2nd to 7th decade (mean 40 years of age)
Squamous Odontogenic Tumor
(SOT)
Clinical charcterstics
- Tumor of Epithelial Origin
- Rare
- Usually asymptomatic, but may present with tooth mobility and slight pain
-
Multiquadrant ~ 20-25%
- A couple reported cases in families
Squamous Odontogenic Tumor
(SOT)
Radiographically
-
Well‐circumscribed radiolucency , often a semilunar radiolucency of alveolar ridge
- Can mimic periodontal disease
Squamous Odontogenic Tumor
(SOT)
Origin
- Thought to arise from epithelial rests (Malassez) in the periodontal ligament space
Squamous Odontogenic Tumor
(SOT)
Treatment
- Treatment is conservative local excision
- Recurrence is rare
Squamous Odontogenic Tumor SOT
Histologically may be mistaken for what other lesions?
- Ameloblastoma
- Squamous cell carcinoma (SCCa)
What is this radiographic finding?
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In addition to fracture, there is semilunar loss of bone around the molars ► (SOT)
Squamous Odontogenic Tumor
What is this radiographic finding?
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SOT
Squamous Odontogenic Tumor
- Semilunar loss of bone.
- Alveolar bone is gone due to impacted canine that is visible
Central odontogenic fibroma (COF)
also known as ?
- *Odontogenic Fibroma
(central) **
Central odontogenic fibroma
(COF)
Origin
- Tumors of Mesenchymal Origin
- Some believe represents the counterpart to the peripheral ossifying (odontogenic) fibroma (in soft tissue)
Central odontogenic fibroma
(COF)
Location
- MX ≈ MD
- lesions in MX tend to be anterior to first molar
- those in MD anterior ≈ posterior
- 1/3 associated with an unerupted tooth
Central odontogenic fibroma (COF)
Clinically
-Small lesion tend to be asymptomatic
-Larger lesions can cause cortical expansion and tooth mobility
Central odontogenic fibroma
(COF)
Radiographically
-
Small lesions tend to be well-circumscribed unilocular radiolucencies
-
often periradicular
- can mimic periapical granulomas and cysts
-
often periradicular
- Larger lesions tend to be well-circumscribed multilocular radiolucencies
- Borders are usually sclerotic
- Root resorption or divergence may be seen
- ~ 10- 15% will show radiopaque flecks within the radiolucency
Central odontogenic fibroma
(COF)
Treatment
- Enucleation with curettage or excision
- usually don’t recur
What is the Microscopic Differential Diagnosis of Central odontogenic fibroma (COF)?
o Desmoplastic fibroma ‐ a more aggressive lesion
o Fibromyxoma ‐ variant of odontogenic myxoma with
abundant collagen
o Hyperplastic tooth follicle ‐ typically loose immature stroma, but when hyperplastic can have abundant collagen
What is this radiographic finding?
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Central odontogenic fibroma (COF)
- well‐circumscribed radiolucency posterior to molar
What is this radiographic finding?
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Central odontogenic fibroma (COF)
round mass of opacity due to FCT. Ground glass‐like appearance
Odontogenic Myxoma
Origin
- Tumors of Mesenchymal Origin
- Thought to arise from the tooth follicle or dental papilla
Odontogenic Myxoma
Demographics and Location
- ~3-5% of all odontogenic tumors
- Wide age range, but 3rd decade most common
- Found anywhere in the MD or MX
Odontogenic Myxoma
Radiographically
- Small lesions present as asymptomatic radiolucencies found upon routine exam
- Larger lesions can cause painless expansion of bone
- All are radiolucent lesions, but the appearance can vary from well‐ circumscribed to irregular and diffuse
- Unilocular to, more commonly, multilocular (“soap bubble” or “honeycomb”) radiolucency
-
Borders are often scalloped, can see sc_alloping around the roots of teeth_
- But can cause displacement of teeth and resorption of the roots of teet
Odontogenic Myxoma
Grossly
- the tumor is described as loose, soft and gelatinous
Odontogenic Myxoma
Treatment
- Surgical excision or resection
- Because the lesion is not encapsulated and has a gelatinous loose consistency► it is difficult to remove completely
- this is thought to be why myxoma has a fairly high recurrence rate
- Maxillary posterior lesions should be treated more aggressively
What is this radiographic finding?
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Odontogenic Myxoma
- Classic example of enlargement of the mandible caused by multilocular radiolucency.
- Enlarged into oral cavity ‐ alveolar ridge elevated
What is this radiographic finding?
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Odontogenic Myxoma
Case
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Clinically: obliteration of vestibule on patient’s left mandible
Radiographically:lesion running from posterior by third molar all the way anterior to canine. Well‐circumscribed, multilocular radiolucency is scalloping up
between teeth, causing some root divergence
Grossly: gelatinous appearance of myxoma makes it hard to remove
After treatment: post‐surgery; had excised all the way to right 2nd PM
This is Odontogenic Myxoma
CEMENTOBLASTOMA
Origin
(True Cementoma)
- Tumor of Mesenchymal origin
- Benign tumor of cementoblasts
CEMENTOBLASTOMA
Demographics and Location
(True Cementoma)
- Typically present in 2nd and 3rd decade (~75% prior to the age of 30)
-
75% MD
- ▪ ~ 90% in molar/premolar region
*
- ▪ ~ 90% in molar/premolar region
CEMENTOBLASTOMA
(True Cementoma)
Clinically
- 2/3 of cases have pain and swelling
- Can cause cortical expansion if large enough
CEMENTOBLASTOMA
(True Cementoma)
Radiographically
- Radiopaque mass fused to the root of the affected tooth
- Usually has a thin radiolucent halo or rim surrounding the radiopacity
CEMENTOBLASTOMA
Treatment
(True Cementoma)
- surgical extraction of the involved tooth with attached tumor
- Root amputation (with attached tumor) and endo is an option for smaller lesions
- Recurrence is unlikely
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CEMENTOBLASTOMA
(True Cementoma)
- First molar has tumor attached to the root.
- Mostly radiopaque but has some less radiodense areas within = classic for cementoblastoma.
- Radiolucent halo around region.
Cementoblastoma has similar histologic presentation to what?
osteoblastoma
Difference is Osteoblastoma is NOT a_ttached to the root of a tooth_ (whereas cementoblastoma must be)
What is this gross and histological finding?
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Cementoblastoma
Grossly continuous growth from tumor to the root of the tooth. Brownish
areas were more vascular.
Histologically: tubular dentin in tooth, attached to mass of tissue with calcifications
What are Odontogenic Tumors
of
Mixed Origin
(Epithelial and
Mesenchymal)
They are tumors in which the _odontogenic epithelial componen_t causes induction of the mesenchymal component to produce a product
Examples:
- Odontomas
- Ameloblastic fibroma
- (and Ameloblastic fibrosarcoma)
- Ameloblastic fibro-odontoma
Odontoma
Origin
- Odontogenic Tumors of Mixed Origin (Epithelial and Mesenchymal
- They are hamartomas rather than true neoplasms
- They are masses of enamel and dentin with variable amounts of pulp and cementum
What is the most common odontogenic “tumor”?
Odontoma
Odontoma
Demographics and Locations
▪ First 2 decade most common (mean age of 14)
Location is based on the type of Odontoma
-
Compound Odontoma
- Anterior jaws (esp. MX)
- **Well developed rudimentary “tooth” forms
-
Complex Odontoma
- Posterior jaws (esp. MD)
- **Poorly developed mass of calcified deposits
Odontoma
Charcterstics
- Often associated with an unerupted tooth
- Lesions may prevent eruption of teeth
- Usually small in size, but rare cases of > 6cm reported
- large lesions can cause bone expansion
Odontoma
Radiographically
▪ Radiographically see a radiopaque structure(s) surrounded by a radiolucent rim
▪ As with any calcified lesion, those found early in development may appear totally or predominantly radiolucent
▪ Compound odontomas appear as small tooth‐like structures
▪ Complex odontomas look like masses of radiopaque material with variable densities
Odontoma
Treatment
▪ Simple excision or enucleation
▪ Unlikely to recur
Compound Odontoma
Vs
Complex Odontoma
Compound Odontoma
- Mature normal appearing pulp, enamel and dentin
- Organization like teeth, with enamel surrounding dentin which surrounds pulp ( Well developed rudimentary “tooth” forms)
- appear as small tooth‐like structures in the Anterior jaws (esp. MX)
Complex Odontoma
- Mature pulp, enamel and dentin
- No organization, mass of dentin and enamel matrix and pulp tissue (**Poorly developed mass of calcified deposits)
- appear as masses of radiopaque material with
- variable densities in the Posterior jaws (esp. MD)
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What is this radiographic finding?
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Classic appearance of Odontoma
- multiple tooth‐like shapes aggregated together
- Typically with some sort of radiolucent halo around them
What is this radiographic finding?
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Compound Odontoma
little teeth‐like structures blocking canine eruption
What is this radiographic finding?
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Complex Odontoma
- 2‐2.5cm mass overlaying the molar.
- radiolucent rim/halo that is mixed, mostly radiopaque
Primordial
odontogenic tumor
(POT)
Origin
- Tumor of mixed origin
- Very rare! first reported in 2014 -less than 30 cases so far
Primordial
odontogenic tumor
(POT)
Demographics and Location
- Most common in 1st and 2nd decades
- Mean age 12.5 years
- MD:MX 6:1
Primordial
Odontogenic Tumor
(POT)
Clinical Charcterstics
- Asymptomatic found on routine imaging
- Can cause tooth displacement and cortical expansion
Primordial
Odontogenic Tumor
(POT)
Radiographically
-
Well-defined radiolucency associated with an impacted tooth
- Most commonly a third molar
Primordial
Odontogenic Tumor
(POT)
Treatment
- conservative excision/enucleation
- So far no recurrence
Case
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Primordial
Odontogenic Tumor
(POT)
unilocular radiolucency
Ameloblastic fibroma (AF) and ameloblastic fibro-odontoma (AFO)
Charcterstics
- Uncommon benign mixed odontogenic neoplasms.
- Considered together because it is thought they are variations of the same process
Ameloblastic fibroma (AF) and ameloblastic fibro-odontoma (AFO)
demographics and location
- Typically presents in first 2 decades
- mean is 12 years of age
- ~ 70% occur in the posterior mandible
- ~ 75% associated with unerupted teeth
Ameloblastic Fibroma (AF)
clinical and radiographic presentations
- Small lesions are asymptomatic and found on routine exam
- Large lesions can cause bone expansion
- Smaller lesions are unilocular Radiolucencies
- Large ones are multilocular radiolucencies
- Border is well defined and often sclerotic
- Untreated, can grow to very large size
What is this radiographic finding?
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Ameloblastic Fibroma
(AF)
1‐3 potential locules, no impacted tooth associated
Ameloblastic Fibro-odontoma (AFO)
Clinical and Radiographic features
- Clinical features similar to Ameloblastic Fibroma AF (Small lesions are asymptomatic and found on routine exam
& Large lesions can cause bone expansion)
Radiographically, we see a mixed radiolucent/radiopaque lesion because of the formation of odontomas
What is this radiographic finding?
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Ameloblastic Fibro-odontoma (AFO)
- well‐circumscribed radiolucency
- corticated edge + calcification
What is this radiographic finding?
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Ameloblastic Fibro-odontoma (AFO)
has expansion into oral cavity. Flecks of calcification
in lesion with impacted tooth = odontoma
Ameloblastic fibroma (AF) and ameloblastic fibro-odontoma (AFO)
Treatment
-
Conservative surgical excision or curettage,
easily removed from surrounding bone - Prognosis is excellent, recurrence is unusual
- ▪ Rare cases reported of development of ameloblastic fibrosarcoma in area of AF or AFO
Ameloblastic
Fibrosarcoma
Charcterstics & Origin
- _Malignant counterpar_t of ameloblastic fibroma
- Rare lesion which may arise in the site of a previous AF/AFO or arise de novo
Ameloblastic
Fibrosarcoma
Demographics and location
- 1.5 times more common in males
- ~ 80% MD
Ameloblastic
Fibrosarcoma
Clinically
- Pain, swelling and rapid growth are common presenting signs
Ameloblastic
Fibrosarcoma
Radiographically
- presents as an ill-defined destructive radiolucency with irregular borders
Ameloblastic
Fibrosarcoma
Treatment
- Radical surgical excision as the tumor is very aggressive and infiltrative
- Prognosis is dependent on complete removal of tumor
What is this radiographic finding?
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Ameloblastic Fibrosarcoma
in the mandible developed after two years from AF
Odontogenic carcinomas
List them (5)
-Ameloblastic carcinoma
-Primary intraosseous carcinoma, NOS
-Sclerosing odontogenic carcinoma
-Clear cell odontogenic carcinoma
-Ghost cell odontogenic carcinoma
All fairly rare lesions!
What is the Differential Diagnosis D/D of Multilocular Radiolucency
MOCHA
- M odontogenic Myxoma
- O Odontogenic keratocyst
- C Central giant cell granuloma
- H Central Hemangioma
- A _A_meloblastoma
Others:
- Aneurysmal bone cyst
- early CEOT
- ameloblastic fibroma AF
- central MECa