10 - Oral Cyst Flashcards
What is the definition of a cyst?
it is a pathological cavity with fluid, semifluid or gaseous contents
What is a cyst lined by?
It is lined by epithelium
How does a cyst develop?
By entrapping epithelial remnants within connective tissue are stimulated to proliferate
Where does a cyst slowly enlarge itself?
in all directions:
- cause a slight high hydrostatic pressure in lumen
- can expand cortex
- can erode roots
How does osmotic pressure influence a cyst?
it can pull fluids into the cyst (moving large proteins)
What are other means of development pathways for cysts?
1.) When normal epithelium lined structure expands
2.) When epithelial cells migrate from lining epithelium to cover the internal aspect of pathologic cavity
What are the 2 types of cysts in oral & maxillofacial regions?
1.) Odontogenic epithelium
2.) Non-odontogenic epithelium
When can odontogenic cysts occur?
They can occur in various stages of odontogenesis
When can non-odontogenic cysts occur?
1.) at an implanted epithelium
2.) In adnexal structures
3.) Salivary tissues
4.) Thyroid
How can cysts occur from?
1.) From inflammatory sources
2.) Developmental causes
What are some clinical implications of cysts?
1.) They depend on the type & location of cyst
2.) The aggressiveness & frequent reccurence
3.) Some cysts are indolent
4.) The type of surgical intervention & follow-up vary within the type of cyst
What are the 4 main classifications of OMF cysts?
1.) Odontogenic cysts
2.) Non-odontogenic cysts
3.) Cysts related to maxillary antrum
4.) Soft tissue cysts
What are pseudocysts? what are some examples of these?
These are not “true” cysts, as they are not lined by epithelium.
e.g:
- simple bone cyst
-strafne bone cyst
-aneurysmal bone cyst
What are odontogenic cysts? & how are they made?
They are cysts derived from odontogenic epithelium
made via:
1.) Developmental cysts
2.) Inflammatory cysts
- Odontogenic keratocysts (OKC)
- Orthokeratinized odontogenic cysts
- Lateral periodontal cyst
- Gingival cyst of adult/newborn
- Dentigerous cyst (follicular cyst)
- Eruption cyst
- Glandular odontogenic cyst
are all examples of what type of odontogenic cyst?
Examples of devlopmental cysts
- Radicular cyst
- Residual cyst
Inflammatory periodontal cyst - Buccal bifurcation cysts
are all examples of what type of odontogenic cyst?
Examples of inflammatory cysts
What are examples of non-odontogenic cysts?
1.) Nasopalatine duct cysts
2.) Nasolabial cysts
3.) Median palatal cysts
What are 2 cyst types related to the maxillary antrum?
1.) Surgical ciliated cyst of the maxillary sinus
2.) Antral pseudocyst
- Mucous extrasvasation cysts
- Mucous retention cysts
- Dermoid, epidermoid & pilar cysts
- Lymphoepithelial cyst
- Branchial cleft cyst
- Thyroglossal duct cyst
are all examples of what kind of cyst?
Soft tissue cysts
What are some radiology description criterias used to summarize a cyst seen on radiographs?
1.) Location (mand, max)
2.) External structure (well defined, ill-defined)
3.) Internal structure (radiolucent vs. radiopaque)
4.) Affect on surrounding tissue (expansion, resorption, destruction)
What are odontogenic keratocysts?
- They are developmental odontogenic cysts (OKC) found in the epithelial rests + enamel organ/dental lamina
Where is odontogenic keratocysts (OKC) most commonly found in?
- Commonly found in both males & females
- 10-40 years of age is the most common, but can affect any age
Where can we commonly find the OKC? (odontogenic keratocysts)
At the posterior mandible
What are some of the histology of OKC’s? (hint: 4 types of descriptions)
1.) Basal cells have a palisading appearance
2.) Nuclear hyperchromatism
3.) Corrugation of the keratin
4.) Satellite cysts are common
What are some radiographic description of an odontogenic keratocyst?
1.) well-demarcated radiolucency
2.) Multilocular or unilocular
3.) Often associated with impacted tooth
4.) Expands in anterior/posterior direction
What are some treatments for odontogenic keratocysts?
1.) Complete excision
2.) Enucleation & curettage (if high reccurence)
3.) Resection (if less recurrence)
4.) Aggressive & high reccurence rate (up to 60%)
What is the prognosis of an OKC?
- When they are aggressive in nature & have a high reccurence rate (10-60%)
- Must ensure all tissue is removed.
What is Gorlin syndrome?
- It is a subtype of an odontogenic keratocyst a.k.a Nevoid basal-cell carcinoma syndrome (NBCCS)
- It is autosomal dominant condition + mutation in PTCH1 gene
What are some of the main features of Gorlin syndrome? (p.33)
1.) Have multiple odontogenic keratocysts
2.) Rib anomalies (bifid ribs)
3.) Vertebral anomalies
4.) Multiple basal cell carcinomas
5.) Palmar plantar pitting
Why do the Orthokeratinized odontogenic cyst differ to the OKC?
1.) They have different histology to the OKC
2.) They do NOT exhibit the same biologic activity as OKC
3.) They are less aggressive
4.) They have a much lower reccurence
What are lateral periodontal cysts?
They are a developmental cyst by which occurs due to a cystic degeneration of epithelial rests.
Who & where are the lateral periodontal cysts most common in? (p.37)
- They are common in males in a 2:1 male to female ratio
- common within the age range of ~50
- Are most common on mandibular biscuspid & canine area
What is the histology of the lateral periodontal cyst?
- thin squamous epithelial cells with clear cells & thickenings
- asymptomatic
- adjacent teeth are vital: must test for vitality
What are the treatments taken to address lateral periodontal cysts?
1.) Surgical removal - enucleation
2.) Low recurrence
What are gingival cysts in adults?
They are a type of developmental cyst described as a soft tissue counter part to the lateral periodontal cyst
How does a gingival cyst present it self in an adult? (p.40-41)
As a fluid filled swelling.
How is a gingival cyst in an adult treated?
- through surgical removal: rule out possibility of OKC
-low recurrence
What is a gingival cyst in a newborn?
They are seen as a discrete white swelling/nodule on the alveolar ridge due to keratin accumulation
Are gingival cysts in newborns common? & how is it treated?
Yes they are common, but rare in patients over 3 months.
It is treated/resolved spontaneously.
What are the nomenclatures of gingival cysts in newborns?
1.) Gingival cyst of newborns
2.) Epstein’s pearls
3.) Bohn’s nodules
Where can gingival cysts in newborns be found?
- Along the alveolar ridge
- From the dental lamina
Where can epstein’s pearls be found in ? (p.45)
- Along the mid palatal raphe
- From entrapped embryonic remnants
Where can Bohn’s nodules be found in ?
- Scattered along the junction of hard & soft palate
- From salivary gland epithelium
What is a dentigerous cyst & where can it be derived from?
It is a subtype of developmental cyst.
It is also known as a follicular cyst.
It can be derived from reduced enamel epithelium
Where does a dentigerous cyst present it self typically?
- usually with an impacted tooth
- usually with 3rd molars + canines (2nd most common)
- can be prone to bone expansion or root resorption
usually in first 3 decades of life
How does a dentigerous cyst present itseld radiographically? (p.49)
As a unilocular radiolucency around unerupted tooth
How do we treat a dentigerous cyst?
- Done by surgical excision of cyst & associated tooth
- Good prognosis
What is the rare occurence that can occur from a dentigerous cyst?
It may rise a ameloblastoma or squamous cell carcinoma that can develop within the cyst wall.
What is an eruption cyst?
It is a developmental cyst.
It is a soft tissue counterpart to the dentigerous cyst derived by reduced enamel epithelium.
How does an eruption cyst present itself clinically? (p.52)
As a bluish soft tissue swelling
How do we treat an eruption cyst?
No treatment is needed. It usually resolves on its own unless it becomes SECONDARILY infected.
Typically resolves itself as the erupting tooth breaks into oral cavity
Tooth eruption usually erupts normally.
What is a glandular odontogenic cyst?
It is a developmental cyst with DUCTAL structures in its epithelial lining.
It has an AGGRESSIVE local behavior.
Who is most affected by glandular odontogenic cysts?
Males & females are EQUALLY affected by this particular cyst.
What is a periapical cyst? (radicular cyst)
It is a type of inflammatory odontogenic cyst
stimulus: non-vital pulp
What is the epithelial source of a periapical cyst?
The rests of Malassez
How is a periapical cyst treated?
- Root canal therapy
- Extraction
What is a residual cyst?
It is a representation of a PERSISTENT periapical cyst that did NOT resolve after tooth extraction.
It typically occurs in the site of an extracted tooth.
How does a residual cyst present itself radiographically?
Unilocular radiolucency in regions of extracted tooth
How is a residual cyst treated?
With conservative excision
What is an inflammatory periodontal cyst?
It is an inflammatory odontogenic cyst.
What are stimuli of an inflammatory periodontal cyst?
- a deep periodontal pocket
- a lateral canal of a non-vital tooth
How is an inflammatory periodontal cyst treated? (p.67)
By removing eliciting irritant:
- periodontal tx for periodontal pockets
- endodontic or surgical tx for non-vital tooth.
What is a buccal bifurcation cyst?
It is an inflammatory cyst that develops along the buccal molar bifurcation + often associated with cervical extensions.
In whom are buccal bifurcation cysts most prevalent in ?
They are EQUALLY prevalent in both males & females.
Where are buccal bifurcations cysts most commonly found?
At the mandibular molar areas.
How are buccal bifurcation cysts seen radiographically?
- They have a radiolucency involving the buccal aspect of the mandibular molars (occlusal radiographs are able to visualize these well)
How is a buccal bifurcation cyst treated? (p.73)
- Enucleation (removal of the cyst as a whole)
- Extraction (may not be necessary all the time)
What is a nasopalatine duct cyst?
It is a NON-odontogenic oral cyst by which is derived from remnants of the nasopalatine duct
Where is the nasopalatine duct cyst located?
It is found at the apical to central incisor roots
How does a nasopalatine duct cyst present itself?
Occasionally as a clinical swelling
What is a difficult assessment to distinguish with a nasopalatine duct cyst? what are some indications of such?
It is sometimes difficult to distinguish the nasopalatine canal. If the duct is >6mm, it is likely a cyst NOT normal anatomy.
Whos is more prone to acquiring a nasopalatine duct cyst? Around what age as well?
Males. in the 4th-6th decade.
What are some treatment options for the nasopalatine duct cyst?
Conservative excision (Recurrence is rare)
What is the soft tissue variant of a nasopalatine duct cyst? (p.79)
Cyst of the incisive papilla.
What is a nasolabial cyst?
It is a non-odontogenic cyst derived from an embryonic remnant of nasolacrimal ducts.
Who is most likely to acquire a nasolabial cyst? & around what age?
Females. Around the ages of 30-50 years.
Where are nasolabial cysts typically found in?
Around the upper lip area, maxillary vestibule. p.80
What are some of the clinical features of a nasolabial cyst?
They are swellings in the muccobuccal fold/canine area.
How can a nasolabial cyst be recognized as a radiographic finding?
No radiographic findings. Usually as a soft tissue lesion.
What are the treatment options for a nasolabial cyst?
Conservative surgical excision.
What is a median palatal cyst?
It is a cyst that is derived from residual epithelium from fusion of palatal shelves.
Where are median palatal cysts typically found?
They are typically located in the posterior midline of the hard palate (generally asymptomatic)
How does a median palatal cyst present itself as?
As an intraoral swelling.
What other non-odontogenic cyst does a median palatal cyst have a similar histologic appearances to?
It has histologic appearances similar to a nasopalatine duct cyst. (p.84)
How is a median palatal cyst managed/treated?
by surgical removal
What is a surgical ciliated cyst of the maxillary sinus?
It is a cyst that is developed when a sinus lining is implanted into the alveolar bone
How does a surgical ciliated cyst arise?
due to procedures to retrieve teeth or foreign bodies from the maxillary sinus (known as the Caldwell-Luc procedure)
What is an antral pseudocyst?
It is an elevation of floor of maxillary sinus in response to inflammation. It has a dome shaped swelling (p.91) - typically from odontogenic origin.
Is treatment required for an antral pseudocyst?
No treatment is required.
What is a mucous extravasation cyst?
It is a soft tissue cyst often termed as a mucocele. It is an example of a pseudocyst, despite the name.
How does a mucous extravasation cyst typically arise?
From the release of mucous after rupture of minor salivary glands.
Where are mucous extravasation cysts typically found in?
On the lower lip. (think of neoplasms if it appears on the upper lip)
How is a mucous extravasation cyst managed?
Typically spontaneously resolve + surgical removal (remove the feeding gland) (p.96)
Is there an epithelial lining on a mucous extravasation cyst? why?
No because it is NOT a true cyst
What is a ranula?
It is a mucous extravasation cyst (mucocele) involving the floor of the mouth.
What is a mucous retention cyst?
It is a dilation of duct of minor salivary gland due to an obstruction which eventually forms a true cyst (epithelium lining present)
How is a mucous retention cyst managed?
By surgical removal (p.101)
What are dermoid & epidermoid cysts?
They are cysts typically occurring on the skin, although dermoid & epidermoid cysts occasionally occur on the floor of the mouth.
How are epidermoid cysts formed by?
They are formed by stratified squamous epithelium (looks like epidermis minus the adnexal structures).
How do dermoid cysts differentiate themselves from the epidermoid cyst?
They have adnexal structures.
What do adnexal structures include?
Sweat glands, hair & sebaceous glands (P.105)
What are lymphoepithelial cysts?
- They are cysts consisting of stratified squamous epithelium within lymphoid tissues.
- Appear as tonsillar crypts trap sloughed keratin & become enlarged
What part of the oral cavity does the lymphoepithelial cysts often involve itself
The floor of the mouth & foliate papilla or oropharynx. (p.107)
How does a lymphoepithelial cyst present itself clinically?
As a yellow nodule.
How is a lymphoepithelial cyst treated?
Must be monitored + surgical excision
What is a branchial cleft cyst?
It is like a lymphoepithelial cyst involving the lateral neck (typically arise from the 2nd branchial (pharyngeal) arch
Where can a branchial cleft cyst present itself typically? in what kind of individual?
Anterior to the sternocleidomastoid muscles. Commonly in young adults.
How is a branchial cleft cyst treated?
By surgical excision. (p.112)
what is a thyroglossal duct cyst?
Cyst that can form anywhere along the tract of the thyroglossal tract (between foramen cecum & thyroid)
What can cause a thyroglossal duct cyst to arise?
Due to remnants of the descent of the thyroid gland
What individual is prone to seeing a thyroglossal duct cyst?
Younger people between ages of 10-30 years of age (p.115)
How does a thyroglossal duct cyst appear on the skin?
Shows as a fistula which is usually around <3cm, but can grow as large as 10cm (p.115-116)
How is a thyroglossal duct treated?
By surgical excision (important to note that it can become cancerous)
What is simple bone cyst?
It is known as a pseudocyst aka traumatic bone cyst with a hollow space within the bone with NO fluid + NO epithelial lining.
In what individual are simple bone cysts more apparent?
Males + younger patients
How are simple bone cysts treated? (during surgery is only an open cavity)
They are treated surgical exploration + induction of bleeding leads to resolution (p.119)
What are stafne bone cysts?
They are stafne defects + stafne bone cavities.
where does a stafne bone cyst typically reside on?
The lingual concavity on the mandible (p.121)
How is a stafne bone cyst typically demarcated ?
Demarcated as a radiolucency below the inferior alveolar canal (thought to be a submandibular gland tissue)
In what individual are stafne bone cysts typically found?
males.
How is a stafne bone treated?
No treatment is required (consider acquiring cone beam CT to confirm diagnosis)
What is a aneurysmal bone cyst?
It is an intraosseous mass of blood filled space (unknown cause)
who is most prone to acquire an aneurysmal bone cyst?
both males & females + usually patients <20 years of age (p.124)
What can aneurysmal bone cyst exhibit clinically + radiographically?
it may exhibit crepitus or a bruit (p.125)
How is an aneurysmal bone cyst treated?
- Surgery (looks like a blood-filled sponge)
