Chapter 15 Flashcards
What do mixed odontogenic tumors consist of?
Epithelium and mesenchymal tissues.
T/F: odontogenic ectomesenchyme tumors have epithelium.
False
What is the name for a cyst that originates by separation of the follicle from around the crown of an unerupted tooth?
Dentigerous cyst.
What is the most common developmental cyst?
Dentigerous cyst.
Where does the dentigerous cyst attach to the tooth?
Covers the crown and attaches on the CEJ.
What is the size for consideration of a dentigerous cyst vs the normal growth space?
3mm.
Where is the most common site for a dentigerous cyst?
Mandibular 3rd molars.
What is the soft tissue analogue of a dentigerous cyst?
Eruption cyst.
What is the likely Dx?
Dentigerous cyst.
What is the term for an eruption cyst when brusing is present?
Eruption hematoma.
What is the likely Dx?
Eruption cyst or eruption hematoma.
Gorlin syndrome is associated with what? (2 names)
What is the reoccurance rate?
Odontogenic Keratocyst or Keratocystic odontogenic tumor
30% reoccurance.
Where is the most common location for an odontogenic keratocyst?
What direction do they tend to grow?
Posterior mandible.
Anterior-posterior direction.
When will an odontogenic keratocyst mimic a dentigerous cyst?
When the tooth is unerupted.
What are the two important histology points with odontogenic keratocyst?
1- Palisading basal cell layer that is hyperchromatic
2- Epithelium covered by wavy or corrugated parakeratin that is 6-8 cell layers thick.
How is an odontogenic keratocyst Dx?
Biopsy.
What is the likely Dx?
Odontogenic keratocyst. Note the multi lobule
What is another name for Gorlin syndrome?
Nevoid Basal Cell Carcinoma Syndrome.
What gene is associated with Nevoid Basal Cell carcinoma Syndrome?
Chromosome 9, PTCH gene.
What is nevoid basal cell carcinoma syndrome characterized by?
1- Multiple basal cell carcinomas
2- Odontogenic Keratocyst
3- Calcification of the falx cerebri
4- Bifid rib anomalies
What is one of the most constant features of nevoid basal cell carcinoma syndrome?
Odontogenic keratocysts.
What is the term for an OKC that has no basal palisading and orthokeratinized lining?
Orthokeratinized odontogenic cyst.
What is the soft tissue counter part of the lateral periodontal cyst?
Gingival cyst of the adult.
Gingival cyst of the adult is derived from what?
Rests of Serres.
Where is the common site of occurance for a gingival cyst of the adult?
Mandibular canine and premolar area.
How do you know that the gingival cyst of the adult will not be one of the 3 P’s?
Because it will be squishy rather than firm.
How are recurrent cysts of odontogenic keratocysts characterized?
Thin wall, friable, daughter cysts.
What is the likely Dx? HINT it is squishy
Gingival cyst of the adult.
A lateral periodontal cyst arises from what tissue?
Rests of dental lamina
What is the likely Dx?
Lateral periodontal cyst.
What is the intrabony counterpart of the gingival cyst of the adult?
Lateral periodontal cyst.
Where is the common occurance of the lateral periodontal cyst?
Mandibular canine to lateral incisor area.
If a lateral periodontal cyst appears poly cystic, what will it be termed?
Botroid odontogenic cysts.
What is the difference between an odontogenic cyst and a dentigerous cyst?
Odontogenic has origins from dental follicle where dentigerous has origins from an impacted tooth.
What is a Gorlin cyst?
Calcifying odontogenic cyst.
What is the term for a developmental cyst with glandular and/or salivary gland features?
Glandular Odontogenic Cycst.
What is the most recently identified odontogenic cyst?
Glandular Odontogenic Cyst.
What is your differential?
Glandular odontogenic cyst and central giant cell granuloma.
What percent of glandular odontogenic cysts occur in the mandible?
75%.
Where will a buccal bifurcation cyst likley develop?
Buccal aspect of the mandibular first permanent molar.
What is the likely Dx? HINT roots are tipped lingually.
Buccal bifercation cyst.
What is the most significant odontogenic tumor?
Ameloblastoma.
Ameloblastomas arise from what tissue?
Odontogenic epithelial origin.
What are the types of ameloblastomas?
Multicystic, unicystic, and peripheral.
Where do the majority of ameloblastomas occur?
In the mandible usually the molar, ascending ramus area.
What is the likely Dx?
Ameloblastoma. Notice the tooth displaced into the ramus.
What are the two descriptors of ameloblastoma?
Soap buble when the RL loculations are large and honeycombed when the locuations are small.
What is unique about the desmoplastic ameloblastoma?
Predilecion for the anterior maxilla.
What are the histopathological features of ameloblastoma?
Palisading hyperchromatic basal layer and reverse polarity.
What is the differential and what is the likely Dx?
Ameloblastoma, Dentigerous cyst, Odontogenic Keratocyst, Central giant cell granuloma.
Likely Ameloblastoma.
What is the likely Dx?
Adenomatoid odontogenic tumor. HINT notice the “snowflake” calcifications and that extends past CEJ differentiating from dentigerous cyst.
Where do adenomatoid odontogenic tumors occur most often?
Anterior jaws.
What is the name for a Pindborg Tumor?
Calcifying Epithelial Odontogenic Tumor.
What is the likely Dx?
Calcifying Epithelial Odontogenic Tumor. HINT notice the snowdriven pattern.
What histopathological test will help you identify calcifying epithelial odontogenic tumor?
It contains amyloid-like extracellular material that will be positive for congo red which exhibits an apple-green birefringence under polarized light.
What is the most common odontogenic tumor?
Odontoma
What are the two forms of odontoma and how do you differentiate them?
Compund: collection of tooth like sturctures, common in anterior maxilla.
Complex: calcified mass that is common in the molar regions.
What is the likely Dx?
Compound odontoma.
What is the likely Dx?
Complex odontoma.
What are Liesegang rings and what are they associated with what?
Calcified amyloid structures in Calcifying epithelial odontogenic tumor.
