SCR Prep

Question 1

What are possible differential diagnoses of ameloblastoma?

Answer 1

• odontogenic keratocyst
• odontogenic myxoma
• ameloblastic fibroma
• ondontogenic fibroma

Question 2

Describe the histopathological appearance of follicular ameloblastoma.

Answer 2

• islands of cells in fibrous tissue
• purple ameloblast-like cells form circles
• stellate reticulum-like tissue forms small white areas within the light purple fibrous tissue
• cystic changes are larger areas of white between tissue
• ameloblast-like cells’ nuclei are located away from the basement membrane “reversed polarity”

Question 3

Which jaw is more commonly affected by ameloblastoma?

Answer 3

Mandible

Question 4

Describe the histopathological appearance of plexiform ameloblastoma.

Answer 4

• strands and irregular masses evident
• ameloblast-like cells’ nuclei display reversed polarity
• cyst degeneration (large white areas)
• stellate like reticulum forms the centre of a target pattern, which cystic changes and epithelium surrounding

Question 5

What is the pathogenesis of ameloblastoma?

Answer 5

Dental lamina (rests of Serrez)

Question 6

What best describes the behaviour of ameloblastoma?

Answer 6

• benign tumour but locally invasive
• high recurrence rate

Question 7

What treatment is recommended for ameloblastoma?

Answer 7

Surgical resection with margin

Question 8

Describe the radiographic appearance of a radicular cyst.

Answer 8

• well defined round radiolucency associated with the root apex of a necrotic tooth
• corticated margins are continuous of with lamina dura
• > 10mm in diameter

Question 9

What is a ranula?

Answer 9

Mucous retaining cyst arising from the sublingual or submandibular glands

Question 10

What is a lateral periodontal cyst?

Answer 10

Forms at the side of a tooth as a result of an accessory canal or as a result of inflammation in a pocket of a vital tooth

Question 11

What is a paradental cyst?

Answer 11

Inflammation around a partially erupted M3M, often associated with an enamel pearl

Question 12

What is an OKC?

Answer 12

Usually affect angle of the mandible, and extend forwards into the body and upwards into the ramus

Question 13

What is a dentigerous cyst?

Answer 13

Surrounds the crown of a tooth and is attached to the ACJ, preventing eruption f the tooth and displacing the associated tooth

Question 14

What is an eruption cyst?

Answer 14

Form in the gum overlying teeth that do not have predecessors

Question 15

What is a residual cyst?

Answer 15

A radicular cyst that has been left behind after extraction of the associated tooth, presents as an isolated radiolucency

Question 16

Describe the histopathological appearance of a radicular cyst.

Answer 16

• non-keratinising stratified squamous epithelial lining (often incomplete)
• connective tissue capsule
• inflammation within the capsule

Question 17

Describe the appearance of a neutrophil.

Answer 17

• round cell with nuclei that are segmented into lobes
• condensed chromatin connected by filaments
• stain blue/purple

Question 18

Describe the appearance of plasma cells.

Answer 18

• ovoid cells with eccentric nuclei
• chromatin clumps arranged like a cartwheel
• stain blue/purple

Question 19

Describe the appearance of a fibroblast.

Answer 19

• spindle shaped cells within fibrous connective tissue
• stain pink/purple

Question 20

What are cholesterol clefts?

Answer 20

• derived from breakdown of RBCs after haemorrhage
• associated with epithelial discontinuities
• crystals found in cyst fluid, clefts are left after preparation for histopathology

Question 21

What are hyaline bodies?

Answer 21

Translucent and pink-staining lamellar bodies that are formed by the cyst lining epithelium

Question 22

What is the treatment of a radicular cyst?

Answer 22

Enucleation

Question 23

Describe the radiographic appearance of a dentigerous cyst

Answer 23

• sclerotic margins
• unilocular radiolucency
• contains crown of unerupted 48 that is displaced

Question 24

Describe the histopathological appearance of a dentigerous cyst.

Answer 24

• thin non-keratinising stratified squamous epithelium
• no significant inflammation

Question 25

Describe the radiographic appearance of a odontogenic keratocyst.

Answer 25

• well defined mulitlocular radiolucent lesion
• corticated margins

Question 26

Describe the histopathological appearance of a odontogenic keratocyst.

Answer 26

• thin keratinised epithelium
• no rete pegs
• palisading of basal cell nuclei
• characteristic corrugated lining
• daughter cysts
• cell nests

Question 27

Why does the presence of inflammation cause an issue for a pathologist looking at a histopathology slide?

Answer 27

Inflamed areas lose the typical diagnostic features

Question 28

Describe the diagnostic findings of a cyst aspirate for an OKC.

Answer 28

• contains epithelial cells
• white or creamy semi-solid material
• low soluble protein >4g/dl

Question 29

What syndrome is OKC associated with?

Answer 29

Gorlin-Goltz syndrome
- basal cell carcinomas
- skeletal abnormalities
- skin pigmentation