Odontogenic Neoplasm/ Tumour Flashcards
Two types of odontogenic tissue?
Mesenchyme
Epithelium
Examples of odontogenic epithelium?
RREDO
Oral epithelium Dental lamina Enamel organ Reduced enamel epithelium Rest of Malassez
Examples of odontogenic mesenchyme?
PFP
Dental papilla
Dental follicle
Periodontal ligament
What gives rise to radicular cyst?
cell rests of mallassez from Hertwigs root sheath
What gives rise to dentigerous cyst?
Reduced enamel epitheloum
What gives rise to keratocyst?
Dental lamina
What types of pathology does dental lamina give rise to?
Ameloblastoma
Keratocyst
How do odontogenic tumours often present?
Radiolucent lesions
Most often angle of mandbile
Why do odontogenic tumours present angle of mandible?
Remnant of dental lamina
How are odontogenic tumours classified?
Benign or malignant
Then epithelium/ mesenchyme or mixed
Example of a benign odontogenic epithelium tunour?
Ameloblastoma
Calcifying epithial odontogenic tumour
Adenomatoid O.T
Example benign epithelial/ mesenchyme tumour?
Odontoma
Ameloblastic fibroma
Example benign odontogenic mesenchyme tumour?
Odontogenic fibroma
Odontogenic myxoma
Cementoblastoma
Is an odontoma a neoplasm?
No
Most common odontogenic neoplasm?
Ameloblastoma - benign epithelial odontogenic tumour
Most common odontogenic mesenchyme tumour?
Myxoma
Most common mixed odontgenic tumour?
Calcifying odontogenic cyst - CEOT less rare
What is ameloblastoma?
Benign but destructive odontogenic epithelial tumour
Where do ameloblastoma present?
Most common site = angle of mandbile
Epidemiology of ameloblastoma?
Age 30-50
More common black population
How do ameloblastoma present clinically?
Often asymptomatic
Can get bucco-lingual expasnion
How does ameloblastoma present on radiograph?
Well defined, radiolucent lesion angle of mandible
Uni or multi-locular appearance
Not cortication
Effect adjacent structures - displacement/ resorption
Where do ameloblasts arise from?
Dental lamina
What are the 3 subtypes of ameloblastomna?
- conventional = intra-osseous
- unicystic = intra-osseous
- peripheral = extra-osseous
Two types of conventional ameloblastoma?
Follicular
Plexiform
Many tunours contain both patterns
What would see in histology of follicular ameloblastoma?
Islands of epithelial tumour, surrounded in fibrous stroma
Epithelium resembles enamel organ
Columnar ameloblast like cells at periphery of islands
Stellate reticulum like area in centre islands
Cysts forming within islands
What would see in histology of plexiform ameloblastoma?
Columnar ameloblast-like cells forming cords
No/ little stellate-reticulum
Cysts form within stroma
Types of unicystic ameloblastoma?
Luminar
Intraluminar
Treatment of unicystic ameloblastoma?
True unicystic ameloblastoma can be enucleated
Management of conventional ameloblastoma?
Requires excision w/ margins
Reconstruction/ bone grafts
What are mutations causing ameloblastoma?
Mandible - BRAF oncogene
Maxilla - SMO oncogene
What is AOT?
Adenomatoid odontogenic tumour - benign
Key feature of AOT?
Benign, not expansile and not destructive
Who see AOT?
Age 10-20
F>M
Where see AOT?
Often in maxilla
Can present radiolucency around crown of tooth
Differential AOT?
Dentigerous cyst
What see radiograph AOT?
Pericoronal radiolucecny - on or around ACJ
See background calcifiication = snow storm
Histology AOT?
Duct-like structures
Calcification realted dentinoid calcified material = snow strom
What can calcifying epithelial odontogenic tumour also be called?
Pindborg tumour
Are CEOT destructive?
Benign and locally destructive
Epidemiology CEOT
Age 10-60
Most in mandibular molar region
What see radiograph CEOT?
Radiolucency with speckled calcification
More calcification w/ age of lesion
Histology of CEOT?
Pleomorphic epithelium w/ dentinoid calcifications
Enamel matrix - may calcific
Cuboidal cells w/ prickles
Variation nuclear size/ shape
What is ameloblastic fibroma?
Benign odontogenic mixed epithelium/ mesenchyme tumour
Epidemiology ameloblastic fibroma?
Less 20 years
Often mandible
80% associatiated unerupted tooth
How does ameloblastic fibroma present?
Well-defined radiolucency
Histology ameloblastic fibroma?
Branching cords and islands of epithelium - resemble enamel organ/ dental lamina
Fine cellular stroma
Possible see dental card tissue
Columnar ameloblast like cells
What is a dentinogenic ghost cell tumour?
Benign odontogenic mixed epithelium/ mesenchyme tumour
Epidemiology of dentinogenic ghost cell tumour?
Very rare
Often 40-60yrs
M>F
How to dentinogenic ghost cell tumours present?
Radiolucency - may have calcification
Large and expansile
Histology dentiongenic ghost cell tumour?
Epithelium resembling ameloblastoma
Ghost cells and dentine
Ghost cells - no nuceli
What is odontome?
Benign odontogenic mixed epithelium/ mesenchyme tumour
Epidemiology odontome?
Developmental abnormalities that grow within growth period of developing dentition - up to 20 yrs
Where to odontomes present?
Mandible or maxilla
How to odontome present?
Radiolucency containing tooth-like structure
Two types of odontome?
Compound and complex
What compound odontoma?
See in maxilla > mandible
See in incisor/ canine regio
Small and non-aggressive
Collection of denticles
What odontome is more common?
Compound
What is complex odontome?
Seen in mandible > maxilla
Premolar/ molar region
Often missing tooth
Fused mass of haphazardly arranged tooth tissue
Why are complex odontome prone to infection?
Irregular form can be focus for bacteria
What is myxoma?
Benign odontogenic mesenchyme tumour
Is myxoma destructive?
Yes, locally
Where do myxoma present?
Mostly in mandible as slow growing, painless swellings
How do myxoma present radiographically?
Uni or multi-locular radiolucecny Well defined Partly corticated Soap-bubble appearnace Root displacement/ resoprtion
Histology myxoma?
Triangular/ stellate cells in loose myxoid stroma
Loose connective tissue w/ struts of bone separating compartments
What are types odontogenic fibroma?
Can be central (arise in bone) or peripheral (arise in gingivae)
How does odontogenic fibroma present radiograph?
Unilocular radiolucency due mature fibrous tissue
Where does cementoblastoma usually present?
Usually mandible - molar teeth
Present radiopaque lesion attached to tooth root
How does cementoblastoma present histologically?
Sheets of cementum and osteoid in mosaic pattern