Odontogenic cysts Flashcards
What is the definition of a cyst?
A pathological cavity with fluid or semi-fluid contents, usually lined by epithelium and not created by pus.
What is the typical presentation of cysts?
Slow growing
Asymptomatic
Found as incidental findings sometimes (radiographs)
What are the dangers of an untreated cyst?
- Infection
- Displacement of teeth
- Bone resorption (increased risk of pathological fracture)
- Bone infection
- De vitalise teeth
- Can impact vital structures
How do you report a radiographic presentation of a cyst?
STOP
S - site, size and shape
T - translucent or opaque
O - outline (well circumscribed etc)
P - any previous imaging
What are odontogenic cysts?
Epithelial lining derived from epithelial residues of tooth forming organ (epithelial rests of serres, reduced enamel epithelium, rests of Malassez)
What is the most common odontogenic cyst?
Radicular cyst
What does a cyst need to grow?
1) source of epithelium
2) stimulus for proliferation of epithelium
3) mechanism of growth and bone resorption
What two categories can odontogenic cysts be?
Inflammatory and non inflammatory
What are the types of inflammatory odontogenic cysts?
- Radicular
- Residual
- Paradental
What are the types of non inflammatory odontogenic cysts?
- Denigerous
- Keratocyst
- Lateral periodontal
- Calcifying odontogenic
- Glandular odontogenic
What is the common sites for a radicular cyst?
Jaws - most common in maxilla (anterior maxilla)
How do radicular cysts present?
- Asymptomatic usually
- Incidental finding on radiograph
What are radicular cysts associated with?
A non vital tooth (usually near apex but can be lateral if a root canal is necrotic)
How would you differentiate between a radicular cyst and periapical granuloma?
The larger the lesion the more likely it is to be a cyst
What are the radiological features of a radicular cyst?
- round or ovoid radiolucency
surrounded by a narrow, radiopaque or corticated margin - extends from lamina dura of involved tooth
What are the features of a residual cyst?
- round or ovoid radiolucency
- well demarcated and often corticated margin
- located in edentulous areas of the jaw
What is the differential cyst for a residual cyst?
Keratocyst
What are the features of a dentigerous cyst?
- odontogenic
- contains/surrounds crown of unerupted tooth
- attaches to the cervical aspect at the CEJ
- develops from expansion of follicle
- eruption cyst
Where is it common to have a dentigerous cyst?
Unerupted third molars and canines
What are the radiological features of a dentigerous cyst?
Radiolucency envelops the crown of an unerupted tooth (only the crown in the radiolucency)
Unilocular
Corticated margin - continuous with lamina dura
Can become large and displace teeth/resorption on adjacent teeth/distort local anatomy
What are the radiological features of an odontogenic keratocyst?
- well defined unilocular radiolucency
- corticated margin
- wide variation
- larger lesions can be multi-locular
- can be associated with unerupted tooth
What condition do you need to be aware of when a OKC is diagnosed?
Gorlin Goltz syndrome
What are the major features of OKC?
- Multiple BCC’s
- OKC of jaw
- 3 or more palmar pits
Falx cerebri calcification
Rib abnormalities
First degree realtive with basal cell nevus syndrome
What is the minor criteria for gorlin goltz syndrome?
Rib abnormalities
Other specific skeletal and radiological abnormalities
Macroencephaly
Cleft lip or palate
Ovarian or cardiac fibroma
Lymph mesenteric cysts
Ocular anomalies
What is an eruption cyst?
Painless, blue or translucent cyst that overlies erupted teeth. Common in children.
What is a lateral periodontal cyst?
Developmental:
Lateral aspect of tooth/between roots of unerupted teeth
Vital tooth
Asymptomatic
Distinct histopathology
Rare
Adults - peak 5th/6th decade
What are the radiological features of a lateral periodontal cyst?
- lateral aspect of tooth between the roots of two teeth
- round/ovoid
- well circumscribed radiolucent area
- corticated, sclerotic margin
- may become tear/pear shaped if teeth are displaced
- usually mid third of root
- mostly <10mm and don’t disrupt lamina dura
What is a multi cystic version of a lateral periodontal cyst called?
Botryoid odontogenic cyst
What is a glandular odontogenic cyst?
-Epithelium resembles salivary/glandular tissue
-Mandible often cross the midline and symmetrical
What are the radiological features of glandular odontogenic cysts?
Well defined, corticated, uni locular or multi, sometimes dentigerous relationship.j
