SCR Prep Flashcards
What are possible differential diagnoses of ameloblastoma?
- odontogenic keratocyst
- odontogenic myxoma
- ameloblastic fibroma
- ondontogenic fibroma
Describe the histopathological appearance of follicular ameloblastoma.
- 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”
Which jaw is more commonly affected by ameloblastoma?
Mandible
Describe the histopathological appearance of plexiform ameloblastoma.
- 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
What is the pathogenesis of ameloblastoma?
Dental lamina (rests of Serrez)
What best describes the behaviour of ameloblastoma?
- benign tumour but locally invasive
- high recurrence rate
What treatment is recommended for ameloblastoma?
Surgical resection with margin
Describe the radiographic appearance of a radicular cyst.
- well defined round radiolucency associated with the root apex of a necrotic tooth
- corticated margins are continuous of with lamina dura
- > 10mm in diameter
What is a ranula?
Mucous retaining cyst arising from the sublingual or submandibular glands
What is a lateral periodontal cyst?
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
What is a paradental cyst?
Inflammation around a partially erupted M3M, often associated with an enamel pearl
What is an OKC?
Usually affect angle of the mandible, and extend forwards into the body and upwards into the ramus
What is a dentigerous cyst?
Surrounds the crown of a tooth and is attached to the ACJ, preventing eruption f the tooth and displacing the associated tooth
What is an eruption cyst?
Form in the gum overlying teeth that do not have predecessors
What is a residual cyst?
A radicular cyst that has been left behind after extraction of the associated tooth, presents as an isolated radiolucency
Describe the histopathological appearance of a radicular cyst.
- non-keratinising stratified squamous epithelial lining (often incomplete)
- connective tissue capsule
- inflammation within the capsule
Describe the appearance of a neutrophil.
- round cell with nuclei that are segmented into lobes
- condensed chromatin connected by filaments
- stain blue/purple
Describe the appearance of plasma cells.
- ovoid cells with eccentric nuclei
- chromatin clumps arranged like a cartwheel
- stain blue/purple
Describe the appearance of a fibroblast.
- spindle shaped cells within fibrous connective tissue
- stain pink/purple
What are cholesterol clefts?
- derived from breakdown of RBCs after haemorrhage
- associated with epithelial discontinuities
- crystals found in cyst fluid, clefts are left after preparation for histopathology
What are hyaline bodies?
Translucent and pink-staining lamellar bodies that are formed by the cyst lining epithelium
What is the treatment of a radicular cyst?
Enucleation
Describe the radiographic appearance of a dentigerous cyst
- sclerotic margins
- unilocular radiolucency
- contains crown of unerupted 48 that is displaced
Describe the histopathological appearance of a dentigerous cyst.
- thin non-keratinising stratified squamous epithelium
- no significant inflammation
Describe the radiographic appearance of a odontogenic keratocyst.
- well defined mulitlocular radiolucent lesion
- corticated margins
Describe the histopathological appearance of a odontogenic keratocyst.
- thin keratinised epithelium
- no rete pegs
- palisading of basal cell nuclei
- characteristic corrugated lining
- daughter cysts
- cell nests
Why does the presence of inflammation cause an issue for a pathologist looking at a histopathology slide?
Inflamed areas lose the typical diagnostic features
Describe the diagnostic findings of a cyst aspirate for an OKC.
- contains epithelial cells
- white or creamy semi-solid material
- low soluble protein >4g/dl
What syndrome is OKC associated with?
Gorlin-Goltz syndrome
- basal cell carcinomas
- skeletal abnormalities
- skin pigmentation
