Odontogenic Cysts and Tumors Flashcards
What is the definition of an Odontogenic cyst?
Pathologic cavity lined by odontogenic epithelium (dental lamina) and filled with fluid or semisolid material
What are 3 odontogenic tumors of epithelial origin?
1-Ameloblastoma
2-Adenomatoid Odontogenic Tumor (AOT)
3-Calcifying Epithelial Odontogenic Tumor (CEOT)
What are 4 mixed odontogenic tumors?
1-Ameloblastic Fibroma
2-Ameloblastic Fibro-odontoma
3-Ameloblastic Fibrosarcoma
4-Odontoma
What are 4 Ectomesenchyme odontogenic tumors?
1-Central Odontogenic Fibroma (COF)
2-Peripheral Odontogenic Fibroma
3-Odontogenic Myxoma
4-Cementoblastoma
A cyst that originates by separation of the follicle from around the crown of an unerupted tooth attaching at the CEJ is called?
Dentigerous cyst
*most commonly Mandibular 3rd molars. Stratified squamous epithelial lining
What is the soft tissue analogue of a dentigerous cyst?
Eruption Cyst
*soft, translucent gingival swelling overlying the crown of an erupting tooth
Arising from the dental lamina, what has a 30% recurrence rate, is associated with a syndrome, and is also called a keratocystic odontogenic tumor (KOT)?
Odontogenic Keratocyst (OKC)
*involves an unerupted tooth 1/3 of the time
In what direction do odontogenic keratocysts tend to grow?
Anterior-Posterior direction
*doesnt cause bone expansion
What is the differential for a multilocular radiolucency?
1-Central Giant Cell Granuloma
2-Ameloblastoma
3-Odontogenic Keratocyst
4-Dentigerous cyst (IF impacted tooth involvement)
A tooth in the inferior border of the orbit is most likely what?
Odontogenic keratocyst
What are the 4 histological characteristics of Odontogenic Keratocysts?
1-Thin, friable wall
2-6-8 cells thick
3-Basal cell layer is palisading and hyperchromatic
4-wavy or “corrugated” parakeratin
What syndrome is due to the PTCH gene on chromosome 9?
Gorlin Syndrome/ Nevoid Basal Cell Carcinoma Syndrome
*know both names
Gorlin Syndrome/ Nevoid Basal Cell Carcinoma Syndrome is characterized by what 4 main things?
1-Multiple basal cell carcinomas (BCCAs)
2-Odontogenic keratocysts
3-Calcification of the falx cerebri
4-Rib anomalies (splayed or bifid ribs)
What odontogenic cysts with orthokeratinized lining and NO basal palisading is most common in the posterior mandible that looks like a dentigerous cyst?
Orthokeratinized Odontogenic Cyst (OOC)
*2% recurrence
What is the soft tissue counterpart to the lateral periodontal cyst, is derived from rests of serres with a predilection for the mandibular canine and premolar area?
Gingival Cyst of the Adult
*Typically facial gingiva around 5 mm
Which developmental odontogenic cyst typically occurs along the lateral root surface, arise from dental lamina and is the intrabony counterpart of the gingival cyst of the adult?
Lateral Periodontal Cyst
How do Lateral periodontal cysts appear radiographically?
Polycystic (multilocular) termed botryoid (“Grapelike”)
AKA gorlin cyst, what has Ghost cells histologically that can calcify?
Calcifying Odontogenic Cyst (COC)
Which developmental cyst with glandular and/or salivary gland features has a predilection for anterior mandible and recur 30% of the time?
Glandular odontogenic Cyst (GOC)
What characteristically develops on the buccal aspect of the mandibular first permanent molar, pushes tooth lingually and occurs during the eruption process?
Buccal Bifurcation Cyst
*Average age 10
What rare condition mimics odontogenic cysts except for having irregular and ragged margins, usually seen in older patients and arise within bone?
Odontogenic carcinoma
What is the most common clinically significant odontogenic tumor, is of odontogenic epithelial origin and usually happens in the 3rd-7th decade?
Ameloblastoma
*usually in molar-ascending rams area
What are the three types of ameloblastoma?
1-Conventional solid or multicystic – 85%
2-Unicystic – 15%
3-Peripheral – 1%
What are two ways the buccal and lingual cortical expansion are described on a radiograph?
1-“Soap bubble” – when the RL loculations are large
2-“Honeycombed” – when the loculations are small
Which type of ameloblastoma does not share features with other forms?
Desmoplastic ameloblastoma
*predilection for anterior maxilla
What are the two main histopathologic features of ameloblastomas?
1-Palisading (hyperchromatic basal layer)
2-Reverse polarity
What painless, nonulcerated, sessile gingival lesion may be clinically interpreted to be one of the 3Ps (bump on the gum)?
Peripheral Ameloblastoma
*Ave age is 50, usually posterior gingival mucosa on mandible
Which non-cancer lesion has histologic features of a conventional ameloblastoma but shows metastatic deposits (usually lungs)?
Malignant Ameloblastoma
Which ameloblastoma lesion has cytologic malignant features and follows markedly aggressive course?
Ameloblastic Carcinoma
*this is a cancer. Later in life
Occuring in younger patients, what has a tendency to occur in the anterior maxilla, specifically involving the canine?
Adenomatoid Odontogenic tumor
*usually discovered on an XRAY when trying to determine why tooth hasn’t erupted
How does an adenomatoid odontogenic tumor appear radiographically?
Snowflake calcifications
*Has thick fibrous capsule
AKA Pinborg Tumor, what is found most often in the posterior mandible with a driven snow radiographic pattern?
Calcifying Epithelial Odontogenic Tumor
What are three features of a Calcifying Epithelial odontogenic tumor?
1-Driven snow Xray
2-Amyloid like material which turns apple green birefringence when stained with congo red
3-Liesgang rings (calcifications)
What true mixed tumor has both epithelial and mesenchymal neoplastic tissues, typically found in the mandible?
Ameloblastic Fibroma
What 4 things make up the differential for an odontogenic cyst/tumor with calcifications?
1- COC (Calcifying Odontogenic Cyst)
2-AOT (Adenomatoid Odontogenic Tumor, impacted Canines are this)
3-CEOT (Calcifying Epithelial Odontogenic Tumor (Driven snow)
4-AFO (ameloblastic fibro-odontoma)
Which lesion appears similat to an ameloblastic fibroma except it also has enamel and dentin?
Ameloblastic Fibro-Odontoma
*Ave age 10
What is the malignant counterpart of the ameloblastic fibroma?
Ameloblastic Fibrosarcoma
*mesenchymal portion shows malignancy
What is the most common odontogenic tumor?
Odontoma
*Ave age 15
Which type of odontoma is composed to multiple, small, toothlike structures?
Compound odontoma
*can see the dentin and enamel layers
Which type of odontoma is composed of a conglomerate mass of enamel and dentin and does not look like a tooth?
Complex odontoma
What lesion occurs on in the jaws and is all mesenchymal?
Odontogenic Myxoma
