Cysts of the Jaws Flashcards
what is a cyst?
pathological cavity having FLUID, SEMI-FLUID, or GASEOUS CONTENTS
NOT CREATED BY ACCUMULATION OF PUS
pus occurs when cyst gets infected
clinical presentation of cyst?
- Discolouration
- Swelling
- result in increased mobility of teeth
- absence of a tooth (maybe unerupted which causing cyst)
- May not have clear signs
rate of progression of a cyst
slow growing generally (but depends on type of cyst)
what initial radiographic investigations can you carry out for diagnosis of a cyst?
- periapical (if suspected small area)
- occlusal (if need larger area)
- OPT
what SUPPLEMENTAL radiographic investigations can you carry out for diagnosis of a cyst?
- Cone beam CT (CBCT)
- Facial radiographs (PA Mandible, Occipitomental view)
Radiographic features of a cyst?
- SHAPE (spherical/egg-shaped)
- NUMBER (single, bilateral, multiple)
- Margins (often well defined, corticated)
- LOCULARITY (often unilocular)
- EFFECT ON SURROUNDING ANATOMY (Displacement of teeth, sinuses, inferior alveolar canal)
signs and symptoms of secondary infection from cysts?
- cysts may lose definition & cortication of margins if secondary infected
- typically associated with clinical signs/symptoms
what are the 3 main classifications of cysts?
Structure: Epithelium-lined vs No epithelial lining
Origin: Odontogenic vs non-odontogenic
Pathogenesis: Developmental vs inflammatory
what is an odontogenic cyst?
- occur in tooth-bearing areas
- most common cause of bony swelling in jaws
- LINED WITH EPITHELIUM
Odontogenic sources of epithelial cells?
RESTS OF MALASSEZ: - Remnants of Hertwig’s epithelial root sheath
RESTS OF SERRES: - remnants of the dental lamina
REDUCED ENAMEL EPITHELIUM: - remnants of enamel organ
names of most common odontogenic cysts?
- radicular cyst
- dentigerous cyst
- odontogenic keratocyst
what is a radicular cyst?
- inflammatory odontogenic cyst (non-vital tooth association)
- usually asymptomatic, if infected results in pain
Radiographic features of a radicular cyst?
- well defined, round radiolucency
- corticated margin continuous with lamina dura of non-vital tooth
- large lesions may displace adjacent structures
- long standing lesions may cause external root resorption
Histology features of radicular cyst?
- epithelial lining (often incomplete)
- connective tissue capsule
- inflammation in capsule
how do radicular cysts form from a granuloma?
- epithelial rests of malassez PROLIFERATES in periapical granuloma
- the epithelium surrounds the fluid area
what are the variants of radicular cysts?
- Residual cyst (persistent cyst after XLA or successful RCT)
- Lateral radicular cyst (associated with an accessory canal)
what is a dentigerous cyst?
- developmental odontogenic cyst (associated with crown of unerupted/impacted teeth)
- cystic change of dental follicle
histology features of dentigerous cyst?
- thin non-keratinised stratified squamous epithelium
what is an eruption cyst?
- variant of dentigerous cyst (contained within soft tissue instead of bone)
- associated with erupting tooth
what is an odontogenic keratocyst (OKC)?
benign but aggressive cysts within the bone that arise from original tooth term and dental lamina
- scalloped margins
- often displace adjacent teeth
- can have significant mesio-distal expansion without bucco-lingual expansion
before an odontogenic keratocyst (OKC) is removed, what type of diagnostic test can be done and what would the findings be to suggest it is an OKC?
- Cyst aspirate
Contains squamous epithelial cells, low protein content
What is basal cell naevus syndrome?
a rare genetic disorder characterized by multiple basal cell carcinomas, skeletal abnormalities, and other developmental defects.
presents as:
- multiple odontogenic keratocysts
- multiple basal cell carcinomas
what are some examples of non-odontogenic cysts?
- nasopalatine duct cyst
- solitary bone cyst
- aneurysmal bone cyst
what is a nasopalatine duct cyst and its presentation?
- developmental non-odontogenic cyst (nasopalatine duct epithelial remnants, in anterior maxilla)
aka incisive canal cyst
Presentation:
- asymptomatic
- salty discharge
- larger cyst may displace teeth/swelling in palate
nasopalatine duct cyst histology features?
- variable epithelial lining
(non-keratinised stratified squamous & modified respiratory)
nasopalatine duct cyst radiology features?
cyst vs incisive fossa?
what is a solitary bone cyst & clinical & radiology presentation?
- non-odontogenic cyst without an epithelial lining
Clinical:
- usually asymptomatic -> incidental finding
- rarely pain or swelling
Radiology:
- found in premolar/molar region mandible
what are the 3 main ways to obtain material for histology?
- aspiration biopsy - drainage of contents
- incisional biopsy - partial removal
- excisional biopsy - complete removal
what are the 2 general surgical options for cysts?
- Enucleation
- Marsupialisation
What is enucleation?
- all of the cystic lesion is removed
what is marsupulisation?
- creation of a surgical window in wall of cyst, remove contents & suturing cyst wall to surrounding epithelium
- encourages cyst to decrease in size & may be followed with enucleation later on
+ve & -ve of enucleation?
+VE:
- whole lining can be examined
- primary closure
- little aftercare
-VE:
- risk mandibular fracture
- cavity left may be infected
- damage to adjacent structures
- Incomplete removal may lead to recurrence
Indications of marsupialisation?
- if enucleation would damage surrounding tissues
- difficult access
- very large cyst with jaw fracture risk
+VE & -VE of marsupialisation?
+VE:
- Simple to perform
- may spare vital structures
-VE:
- opening may close & cyst may reform
- Complete lining not available for histology
- long time to fill in space
