Cysts Flashcards
What is dental lamina?
Oral epithelium that gives rise to enamel organ of developing tooth
Where are remnants of dental lamina found?
Often angle of mandible
What is a follicle?
Odonogenic mesenchyme that surrounds unerupted tooth
How is follicle formed?
Formed from external and internal epithelium of enamel organ
What are rests of malassez?
Remnants of Hertwig’s root sheath and normal components of PDL
What is reduced enamel epithelium?
Residual epithelium of enamel organ - attached ACJ
What expect to see radiograph radicular cyst?
Large well defined radiolucency
Can be corticated
Continuity w/ PDL
What can be differential of radicular cyst?
Periapical granuloma
What look for on histology of radicular cyst if root present?
Look root canal system for viable pulp cells - likely to see necrotic
What is main components of cyst?
Wall, lining and lumen
What is wall of radicular cyst?
Fibrous connective tissue - may see chronic inflammatory cells
What is lining of radicular cyst?
Non-keratinised stratified squamous epithelium
Where does radicular cyst originate from?
Rest cells of mallassez - remnants of Hertwigs root sheath
What can see in lumen of radicular cyst?
Debris
Cholesterol clefts
Why do cholerstoral crystals from?
Due extensive cell destruction
Why do radicular cysts form?
Non-vital pulp = periapical granuloma
Ongoing inflammation = tissue destruction = granulation tissue formation
Cause proliferation odontogenic epithelium
Likely source of epithelium in radicular cyst?
Cell rests of malassez - arise in PDL
How does epithelium proliferation occur in cyst?
Inflammatory infiltrate acts upon epithelium = stimulate grow
How goes radicular cyst grow?
Accumulation of fluid - hypertonic so draws fluid - this causes pressure in cyst causing expansion
Treatment options for radicular cyst?
Unrestorable - XLA and enucleatre
Restorable - endodontic and peri-radicular surgery
What note when describing radiograph?
General overview inc caries Radiolucency - Definition - Size - Extension - Associated displacement - teeth/ ID - Associated resorption - Corticated - Expansion
Different types of follicular cyst?
Dentigerous - associated w/ impacted tooth
Eruption
On histology where does follicular cyst attached tooth?
ACJ
Is any inflammation wall of dentigerous cyst?
No
Developmental odontogenic cyst
What is wall and lining of dentigerous cyst?
Wall = fibrous connective tissue, no inflammation Lining = thin non-keratinised SSE
Source of lining for dentigerous cyst?
Reduced enamel epithelium
What teeth are commonly affected by dentigerous cysts?
Lower third molars
Maxillary canines
Second mandibular premolars
What appearance is common for odontogenic keratocyst on X-ray?
Scalloped egden
Differential diagnosis for odontogenic keratocyst?
Radicular cyst
Odonotgenic tumour
Where is most likely site for odontogenic keratocyst?
Posterior mandible - most common site of dental lamina
What is the epithelial lining of odontogenic keratocyst?
Para-keratinised SSE
See nuclei parallel - nuclear palisading
Source of epithelium in odontogenic keratocyst?
Dental lamina
What clinical tests can help establish diagnosis of odontogenic keratocyst?
Sensibility testing - rules out radicular cyst
Imaging - if any expansion
Aspiration cyst content
Do see expansion with odontgenic keratocyst?
No
More likely to see in tumour
Why do odontogenic keratocyst recur?
Thin fragile lining
Daughter cells
What condition is odontgoenic keratocyst often seen in?
Gorlin goltz
Differential diagnosis for radiolucency in anterior maxilla?
Radicualr cyst
Nasopalatine duct cyst
What is epithelium on nasopalatine duct cyst?
Columnar pseudostatified epithelium (respiratory)
Source of epithelium for nasopalatine duct cyst?
Remnants of epithelium from fusing of palatine shelf and pre-maxilla
