Benign Odontogenic Tumors Dr. T Flashcards
1
Q
What is the relationship between lesion’s agrressivness, rate of reccurance and follow up duration ?
A
the more aggressive the biologic behavior, the higher risk of
recurrence, and the longer the follow up needed for the patient
2
Q
What is the spectrum of benign and malignant lesions
A
3
Q
Which lesions are considered benigns
A
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
4
Q
which lesions are on the malignant side?
A
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.
5
Q
What are the 3 Classification of
benign tumors?
A
- Epithelial
- Mesenchymal
- Mixed
6
Q
What are the list of Epithelial Benign Tumors?
(5)
A
▪ Ameloblastoma
▪ Adenomatoid odontogenic tumor
▪ Calcifying epithelial odontogenic tumor
▪ Squamous odontogenic tumor
▪ Odontogenic keratocyst (aka Keratocystic odontogenic tumor)
7
Q
What are the list of Mesenchymal Benign Tumors?
(5)
A
▪ Odontogenic myxoma
▪ Central Odontogenic fibroma
▪ Cementifying fibroma
▪ Cementoblastoma
▪ Granular cell odontogenic tumor
8
Q
What are the list of Mixed Benign tumors?
5
A
▪ Odontoma (complex and compound)
▪ Ameloblastic fibroma/odontoma
▪ Primordial odontogenic tumor
▪ Dentinogenic ghost cell tumor
▪ Calcifying cystic odontogenic tumor(aka COC, ghost cell tumor)
9
Q
Ameloblastoma
Charcterstics
A
- An epithelial odontogenic neoplasm (Tumor of Epithelial Origin)
- with a close histologic resemblance to the enamel organ
10
Q
Ameloblastoma
Origin
A
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
11
Q
Ameloblastoma
Radiographically
A
-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
12
Q
Ameloblastoma
Clinically
A
- 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)
13
Q
Ameloblastoma
Demographics
A
▪ 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)
14
Q
ameloblastoma
location
A
▪ 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
15
Q
Ameloblastoma
Etiology
A
▪ 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
16
Q
What is
the second most common
odontogenic neoplasm?
A
Ameloblastoma
(after odontoma)
o although odontomas are more like hamartomas
17
Q
Which tumor can arise in a dentigerous cyst?
A
Ameloblastoma
(we see transition from stratified squamous to ameloblastic epithelium)
18
Q
Ameloblastoma
Types
A
Conventional/multicystic/solid/ (~ 80%)
- Unicystic (~6-15%) need entire specimen (excision) to know
- Desmoplastic
- Peripheral
- Malignant
19
Q
What is this radiographic finding?
A
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
20
Q
What is this radiographic finding?
A
▪ 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
21
Q
What is this radiographic & clinical finding?
A
Ameloblastoma
clinically: Have expansion of the buccal plate, obliterating the vestibule in this area.
Radiographically: Root resorption of molar, unilocular radiolucency in mandible
22
Q
What is this radiographic finding?
A
Ameloblastoma
- Small lesion distal to impacted tooth.
- Unilocular radiolucency with elevation of alveolar ridge + some expansion of soft tissue
23
Q
What is this radiographic finding?
A
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
24
Q
Conventional/Solid Ameloblastoma
Treatment
A
- 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
25
**Case**
**16yo female**
Describe the lesion and what is the diagnosis?
▪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 adjacen**t (PMs and molar)
**Ameloblastoma**
26
Case
## Footnote
▪ **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**
27
**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.***
28
**Unicystic Ameloblastoma**
_Demographcics and Locations_
▪ **Younger initial presentation** (~ 50% in ***2nd decade***)
▪ **90% in MD (mandibular)**
▪ Typically _asymptomatic and found on routine radiographic exam_
29
**Unicystic Ameloblastoma**
_Radiographically_
* Commonly **a well‐circumscribed radiolucency** that _surrounds the crown of an unerupted tooth_
* Commonly accompanied by **_root resoprtion_**
30
**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_
31
What is this radiographic finding?
**Unicystic Ameloblastoma**
but could be
**Dentigerous Cyst**
based on clinical presentation!
So radiograph is not diagonstic
32
**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_***
33
**Desmoplastic
Ameloblastoma**
_Location_
* **Anterior jaws** (particularly **maxilla**)
34
**Desmoplastic
Ameloblastoma**
_Radiographically_
* looks **“fibro‐osseous”** due to **mixed radiolucentradiopaque** **appearance**
* Mineralization of **dense collagen**
* **Well‐circumscribed**, _corticated_.
35
What is this radiographic finding?
Desmoplastic
Ameloblastoma
* **Spherical growth**. Within it, has both radiodense and radiolucent areas (is
* **mixed radiolucent‐radiopaqu**e)– similar appearance to *_benign fibro‐osseous lesions._*
* **Well‐circumscribed, corticated**.
36
**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_*
37
**Peripheral
Ameloblastoma**
_location_
* Found on **gingiva or alveolar mucosa (**\*that's why it's named *peripheral* or extraosseous)
38
**Peripheral
Ameloblastoma**
39
What are the two types of **“Malignant”
Ameloblastomas ?**
1. **Malignant ameloblastoma**
2. **Ameloblastic carcinoma**
40
What is a **malignant ameloblastoma?**
▪ Malignant ameloblastoma
o Primary lesion and metastasis have normal welldifferentiated
ameloblastic (benign) histology
o Most commonly to lung
41
What is **Ameloblastic carcinoma?**
* **a primary lesion** has _atypical poorly‐differentiated_
* _neoplastic_(malignant) histology
* **may metastasize**
42
**CALCIFYING EPITHELIAL ODONTOGENIC TUMOR**
**CEOT**
also known as ?
**Pindborg Tumor**
43
Calcifying Epithelial Odontogenic Tumor
(CEOT)
▪ Uncommon (~1% of odontogenic tumors)
▪ Does not have inductive effect
44
**Calcifying Epithelial Odontogenic Tumor**
**(CEOT)**
_Demographics and Location_
o **2nd to 10th decade**s, peak **~ 4th decade**
o **MD (mandibular) 2 : 1 MX (maxillary)**
o Usually ***posterior mandible***
45
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**
46
**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.*
47
**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***
48
**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*
49
**case**
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***_
50
What is this radiographic finding?
**Calcifying Epithelial Odontogenic Tumor(CEOT)**
* **flecks of calcifications.**
* **Calcifications** all around crown is common
51
What is this radiographic finding?
**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.**
52
What is this radiographic finding?
**Calcifying Epithelial Odontogenic Tumor(CEOT**)
* ***Fewer calcifications here***, **well‐circumscribed and corticated, impacted** tooth.
* **periosteal reaction** _causing elevation_ at the bottom of image!
53
**Calcifying Epithelial Odontogenic Tumor(CEOT)**
* **well‐circumscribed radiolucency with calcifications** *_in lower anteriors_*
54
**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*
55
**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*
56
Adenomatoid odontogenic tumor
(AOT)
_Origin_
* thought to arise from ***remnants of the dental lamina in the gubernacular cord /canal***
57
**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_
58
If an **Adenomatoid odontogenic tumor (AOT)** is not showing any calcifications yet, it’s in the differential
diagnosis with ------ ?
**a dentigerous cyst.**
59
**Adenomatoid odontogenic tumor**
**(AOT)**
_Treatment_
* Treatment is usually **_enucleation_**
* _recurrence_ is ***rare***
60
What is the DD?
**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**
61
What is this radiographic finding?
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)**
62
What is this clinical finding?
Adenomatoid odontogenic tumor
(AOT)
**Swelling in maxillary vestibule**
63
What is this clinical finding?
**Adenomatoid odontogenic tumor**
**(AOT)**
fibrous capsule of AOT is at least partially encapsulated.
Easy to remove; “popped right out”.
64
What is this clinical finding?
**Adenomatoid odontogenic tumor**
**(AOT)**
An expansion _into lingual area_ as well as _into vestibule_
65
What is this radiographic finding?
_Adenomatoid odontogenic tumor_
_(AOT)_
**Snowflake‐like calcifications** within ***mixed, well‐circumscribed radiolucency***
66
What is this radiographic finding?
Adenomatoid odontogenic tumor
(AOT)
* **Teardrop shape / inverted pear** _between roots of teeth_.
* **Well-circumscribed, corticated margin** & **snowflake‐like calcifications** *within*
67
**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)
68
**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*
69
**Squamous Odontogenic Tumor**
**(SOT)**
_Radiographically_
* **Well‐circumscribed radiolucency** , often ***a semilunar radiolucency of alveolar ridge***
* Can mimic _periodontal disease_
70
**Squamous Odontogenic Tumor**
**(SOT**)
_Origin_
* Thought to arise ***from epithelial rests (Malassez) in the periodontal ligament space***
71
**Squamous Odontogenic Tumor**
**(SOT)**
_Treatment_
* Treatment is **conservative local excision**
* _Recurrence_ is ***rare***
72
**Squamous Odontogenic Tumor** **SOT**
Histologically may be mistaken for what other lesions?
* **Ameloblastoma**
* **Squamous cell carcinoma (SCCa)**
73
What is this radiographic finding?
In addition to *fracture*, there is **semilunar loss of bone around the molars ►** (SOT)
**Squamous Odontogenic Tumor**
74
What is this radiographic finding?
**SOT**
**Squamous Odontogenic Tumor**
* ***Semilunar** loss of bone*.
* **Alveolar bone** is gone due to **impacted canine** that is visible
75
**Central odontogenic fibroma (COF)**
also known as ?
* *Odontogenic Fibroma
(central) **
76
**Central odontogenic fibroma**
**(COF)**
_Origin_
- Tumors of Mesenchymal Origin
- Some believe represents **the counterpart to the peripheral ossifying (odontogenic) fibroma** *(in soft tissue)*
77
**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**
78
**Central odontogenic fibroma (COF)**
_Clinically_
*_-Small lesion_* tend to be **asymptomatic**
-*_Larger lesions_* can cause **cortical expansion and tooth mobility**
79
**Central odontogenic fibroma**
**(COF)**
_Radiographically_
* *Small lesions* tend to be **well-circumscribed unilocular radiolucencies**
* **often periradicular**
* can mimic periapical granulomas and cysts
* *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_
80
**Central odontogenic fibroma**
**(COF)**
_Treatment_
* **Enucleation** with **curettage** or **excision**
* usually d**on’t recur**
81
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*
82
What is this radiographic finding?
Central odontogenic fibroma (COF)
* **well‐circumscribed radiolucency** *posterior to molar*
83
What is this radiographic finding?
Central odontogenic fibroma (COF)
round mass of opacity due to FCT. **Ground glass‐like appearance**
84
**Odontogenic Myxoma**
_Origin_
* Tumors of *Mesenchymal Origin*
* Thought to arise from ***the tooth follicle or dental papilla***
85
**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***
86
**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**
87
**Odontogenic Myxoma**
_Grossly_
* the tumor is described as **loose**, **soft** and **gelatinous**
88
**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_
89
What is this radiographic finding?
**Odontogenic Myxoma**
* Classic example of **enlargement of the mandible** caused by **multilocular radiolucency.**
* Enlarged into oral cavity ‐ **alveolar ridge elevated**
90
What is this radiographic finding?
**Odontogenic Myxoma**
91
Case
**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**
92
**CEMENTOBLASTOMA**
_Origin_
| (True Cementoma)
* Tumor of *Mesenchymal* origin
* **Benign tumor** of *cementoblasts*
93
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**
*
94
**CEMENTOBLASTOMA
(True Cementoma)**
_Clinically_
* **2/3** of cases have **pain and swelling**
* Can cause **cortical expansion *_if large enough_***
95
**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_
96
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***
97
**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.
98
**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)
99
What is this gross and histological finding?
**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
100
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
101
**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_**
102
What is **the most common odontogenic “tumor”**?
**Odontoma**
103
**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**
104
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**
105
**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**
106
**Odontoma**
_Treatment_
▪ **Simple excision** or **enucleation**
▪ **Unlikely** *to* **recur**
107
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)
108
What is this radiographic finding?
Classic appearance of **Odontoma**
* **multiple tooth‐like shapes** *aggregated together*
* Typically with some sort of **radiolucent halo around them**
109
What is this radiographic finding?
**Compound Odontoma**
_little teeth‐like structures_ blocking canine eruption
110
What is this radiographic finding?
**Complex Odontoma**
* _2‐2.5cm mass overlaying the molar_.
* ***radiolucent rim/halo*** that is **mixed**, *mostly* **radiopaque**
111
**Primordial
odontogenic tumor
(POT)**
**Origin**
* Tumor of mixed origin
* Very rare! first reported in 2014 -**less than 30 cases so far**
112
**Primordial
odontogenic tumor
(POT)**
_Demographics and Location_
* Most common in **1st and 2nd decades**
* Mean age **12.5 years**
* **MD:MX 6:1**
113
**Primordial
Odontogenic Tumor
(POT)**
_Clinical Charcterstics_
- **Asymptomatic** found on routine imaging
- Can cause **tooth displacement** and **cortical expansion**
114
**Primordial
Odontogenic Tumor
(POT)**
_Radiographically_
* **Well-defined radiolucency** _associated with_ **an impacted tooth**
* Most commonly **a third molar**
115
**Primordial
Odontogenic Tumor
(POT)**
_Treatment_
* **conservative excision/enucleation**
* So far ***no recurrence***
116
Case
Primordial
Odontogenic Tumor
(POT)
**unilocular radiolucency**
117
Ameloblastic fibroma (AF) and ameloblastic fibro-odontoma (AFO)
_Charcterstics_
* _Uncommon_ ***benign* mixed** odontogenic neoplasms.
* **Considered together b**ecause it is thought they are _variations of the same process_
118
**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**
119
**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_
120
What is this radiographic finding?
**Ameloblastic Fibroma
(AF)**
1‐3 potential locules, no impacted tooth associated
121
**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_
122
What is this radiographic finding?
**Ameloblastic Fibro-odontoma (AFO)**
* _well‐circumscribed radiolucency_
* ***corticated edg***e + **calcification**
123
What is this radiographic finding?
**Ameloblastic Fibro-odontoma (AFO)**
has expansion into oral cavity. Flecks of calcification
in lesion with impacted tooth = odontoma
124
**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_
125
**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
126
**Ameloblastic
Fibrosarcoma**
_Demographics and location_
* **1.5 times** _more common_ in **males**
* ~ **80% MD**
127
**Ameloblastic
Fibrosarcoma**
_Clinically_
* **Pain**, **swelling** and **rapid growth** are *common presenting signs*
128
**Ameloblastic
Fibrosarcoma**
_Radiographically_
* presents as an **ill-defined destructive radiolucency** *with* **irregular borders**
129
**Ameloblastic
Fibrosarcoma**
_Treatment_
- **Radical surgical excision** as the tumor is ***very aggressive*** *and* ***infiltrative***
- _Prognosis_ is *dependent on* **complete removal of tumor**
130
What is this radiographic finding?
**Ameloblastic Fibrosarcoma**
in the mandible developed after two years from AF
131
**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!
132
What is the Differential Diagnosis D/D of **Multilocular Radiolucency**
**MOCHA**
* **M odontogenic **_M_**yxoma**
* **O **_O_**dontogenic keratocyst**
* **C **_C_**entral giant cell granuloma**
* **H Central **_H_**emangioma**
* **A _A_meloblastoma**
**Others:**
* Aneurysmal bone cyst
* early CEOT
* ameloblastic fibroma AF
* central MECa
