Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Oral Disease > Cysts of the Face and Jaws > Flashcards

Cysts of the Face and Jaws Flashcards

1
Q

Definition of a Cyst

A

Pathological cavity containing fluid, semi-fluid or gaseous material which is not produced by the accumulation of pus.
Cysts are often lined by epithelium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is needed for a cyst to develops (3 points)

A
  1. Source of epithelium
  2. Stimulus to make it proliferate
  3. Mechanism to allow it to enlarge
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is found in cysts histologically (common features)

A

Common for part of the lumen to invaginate, pushing material including cholesterol clefts and inflammatory cells (mural nodes) into the cavity
Usually a thin layer of reactive, woven bone is found just outside the wall
Lumen
Inflammation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Relative incidence of cysts

A
  • Radicular cysts 45%
  • Residual radicular 7%
  • Dentigerous cysts 16%
  • Odontogenic keratocyst 10%
  • Incisive canal 10%
  • Collateral 3%
  • Lateral periodontal <1%
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Cyst classification

A

Cysts can be odontogenic OR non-odontogenic AND of inflammatory OR developmental origin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which cysts are classified as odontogenic inflammatory cysts

A

Radicular cysts
residual cysts
inflammatory collateral cysts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Radiographic features of a radicular cyst

[site, size, shape, outline, relative radiodensity, effect on adjacent structures]

A

site: upper laterals
size: varies depending on when lesion is found but usually a few cm
shape: unilocular
outline: well defined and corticated
relative radiodensity: uniformly radiolucent
effect of adjacent structures: tilting of teeth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How do radicular cysts form

A

Usually starts as an apical granuloma in which non-keratinised epithelium (cell rests of Malassez) proliferates in response to inflammation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Where is a radicular cyst usually located?

A

At the apex of a non-vital tooth (sensibility tests important) - more common in upper lateral region and males

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Histology of all odontogenic inflammatory cysts

A
  • Non-keratinised stratified epithelial lining
  • Thick fibrous wall
  • Inflammation an dense inflammatory infiltrate (mural nodules)
  • Cholesterol clefts and cholesterol crystals found in wall and lumen (common when long-standing inflammation)
  • Hyaline/Rushton Bodies (10% of all odontogenic cysts)
    formed as a result of epitheial cells secreting dental cuticle on to cholesterol (if identified must be of odontogenic origin)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How are radicular cysts diagnosed

A

Recognised through clinical and radiographic features

Histological examination essential to confirm diagnosis post-op

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How is a residual cyst formed

A

A radicular cyst that has persisted after extraction of the causative (non-vital) tooth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How does a residual cyst present

A

Present with expansion of jaw (fluid refills and begins growing)
More common in older people so can be possible reason for denture not fitting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the histology of a residual cyst?

A
  • Same as radicular cyst
  • inflammation subsides as the cause is removed, so growth is very slow
  • Mural nodules disappear
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Where do inflammatory collateral cysts arise

A

From epithelium near the furcation of molars

  • tooth is vital
  • classically lower 8s
  • bilateral
  • More common in taurodontism
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Cause of inflammation for collateral cysts

A

Likely cause of inflammation is pericoronitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How does a collateral cyst appear histologically

A

Similar to radicular cyst

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Why do inflammatory cysts enlarge?

A
  • Radicular cysts have an internal hydrostatic pressure of 60-100cm water
  • This is partly osmotic due to semi-permeable membrane (lining excludes albumin if intact but there is leakage)
  • Protein with higher molecular weight is secreted into cysts e.g. immunoglobulin
  • Proteins in cysts are degraded and there is poor lymphatic drainage
  • Internal pressure probably fluctuates with inflammation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How do cysts resorb bone?

A
  • Pressure from contents can induce bone resorption
  • Inflammatory mediators from the wall can induce resorption
  • Bone is only removed by osteoclasts
  • Can result in expansion of the jaw due to resorption of the cortex (underneath) and pushing out of the periosteum which covers bone (as cyst is in bone)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How fast do inflammatory cysts grow

A
  • slowly
  • to 2cm diameter in 10 years
  • in children, to 5cm diameter in 2 years
  • once in antrum, nose or mouth, expansion is rapid
  • slow growth allows expansion around neurovascular bundles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

The growth pattern of a cyst can give an indication to the cyst type

A
  • All inflammatory cysts enlarge under pressure and tend to be spherical
  • But the shape is constrained by resistant tissues (cortical bone, teeth, mucoperiosteum)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Which cysts are classified as odontogenic cysts of developmental origin

A
  • Dentigerous
  • Odontogenic Keratocyst
  • Lateral Periodontal cyst
  • Glandular odontogenic cyst
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Features of a dentigerous cyst?

Where does it occur commonly

A
  • Developmental cyst that contains the crown of an unerupted tooth
  • It has an epithelial lining attached at the CEJ derived from the reduced enamel epithelium
  • Prevents eruption of the tooth and may displace it for a considerable distance
  • Most common on lower 8s, upper 8s and upper 3s (often impacted teeth)
24
Q

Radiographic features of a dentigerous cyst

[site, size, shape, outline, relative radiodensity, effect on adjacent structures]

A

site: around the crown of a tooth (8s, 3s and 5s)
size: variable (larger than 10cm)
shape: unilocular
outline: well defined and corticated
relative radiodensity: uniformly radiolucent
effect of adjacent structures: often expands the jaw with loss of lamina dura

25
Q

How do differentiate between radicular an dentigerous cysts

A

Features of both are similar
Cannot 100% determine from radiography if epithelial lining is attached to CEJ
so sensibility test for potential teeth in question is important to determine vitality and achieve a differential diagnosis

26
Q

Histology of dentigerous cyst

A
  • Reduced enamel epithelium separates from enamel to form the cyst cavity
  • REE (usually 2 cells thick) thickens to form stratified non-keratinised epithelium
  • Once significant inflammation supervenes, resembles radicular cyst
27
Q

Growth pattern of dentigerous cyst

A

tends to grow centrifugally based on similar principles to the radicular cyst
has internal hydrostatic pressure

28
Q

Diagnosis of dentigerous cyst

A
  • relationship of cyst to tooth (clear attachment at CEJ)
  • possible to diagnose through clinical and radiographic examination alone
  • histological diagnosis to confirm post-op
29
Q

Features of an odontogenic keratocyst

A
  • Tendency to recur
  • Most commonly found at the angle of the mandible, behind or instead of 8s
  • Arise from odontogenic rests (Cell rests of Serres)
  • Feature of Basal Cell Naevus Syndrome
  • Does not displace adjacent structures but if large can risk fracture of mandible
30
Q

Radiographic features of a odontogenic keratocyst

[site, size, shape, outline, relative radiodensity, effect on adjacent structures]

A

site: posterior mandible
size: variable but becomes very large
shape: unilocular, multilocular (mainly) or pseudolocular
outline: well defined and corticated in parts
relative radiodensity: radiolucent but radiopaque septa if multilocular
effect of adjacent structures: grows through bones with no effect on adjacent structures

31
Q

Histopathology of odontogenic keratocyst

A
  • Regular stratified squamous epithelium
  • thin epithelial layer (5-8 cells thick)
  • palisaded basal layer
  • hyaline bodies
  • satellite (daughter) cysts within wall also common
32
Q

How do odontogenic keratocysts grow

A
  • no internal pressue
  • enlargement is by growth of lining
  • lining has high mitotic growth activity and the wall secretes bone resorbing factors
  • growth is burrowing along path of least resistance
  • cortical bone is not resorbed and teeth are not displaced
33
Q

Recurrance in odontogenic keratocyts

A
  • up to 40% recur

- thin fragile wall makes it hard to enucleate intact

34
Q

Basal Cell Naevus syndrome mutation

A
  • Autosomal dominant mutation of patched gene (PTCH) which is a tumour suppressor gene controlling the cell cycle via the hedgehog signalling pathway
  • inheriting one mutant allele cause skeletal features
  • inheriting a second allele causes basal cell carcinoma and odontogenic keratocysts develop
35
Q

Clinical features of Basal Cell Naevus syndrome

A
  • Multiple odontogenic keratocysts
  • multiple basal cell carcinomas of the skin
  • bifid, fused and supernumerary ribs
  • frontal bossing
  • mild skeletal class III
  • skin pitting
36
Q

Should all odontogenic keratocysts be considered benign neoplasms

A

YES

  • recur
  • aggressive
  • soft tissue spread
  • may develop dysplasia/malignancy
  • association with patched gene mutation

NO

  • relative aggression
  • resolve on marsupialisation
  • can remove effectively but not conservatively
  • recurrence rates low in best centres, with Carnoy’s solution
37
Q

Features of lateral periodontal cyst

A
  • canine/premolar region
  • adjacent teeth vital
  • thin epithelial lining with plaque like thickenings
  • probably derived from cell rest of malassez but not inflammatory process
  • unilocular
38
Q

Glandular odontogenic cyst features

A
  • Mucoepidermoid odontogenic cyst mostly in mandible
  • Flat epithelium with or without plaques
  • thickenings with duct like spaces secreting mucin
  • may grow large and recur
  • multi or unilocular
39
Q

Which cysts are classified as non-odontogenic developmental cysts

A
  • Incisive canal cyst

- Nasolabial cyst

40
Q

Features of incisive canal cyst

A
  • arises from epithelium in incisive canal (lined by respiratory epithelium or stratified squamous epithelium
  • blood vessels and nerves in wall (not usually found in odontogenic cysts)
  • presents as swelling over incisive canal or mucoid/salty discharge into nose or mouth
  • associated teeth are vital
41
Q

Features of nasolabial cyst

A
  • Probably developmental disturbance of nasolacrimal duct
  • cyst outside the bone in the soft tissues
  • lined by respiratory epithelium
  • identified in nasolabial fold, upper buccal sulcus an dlip
  • may erode bone of anterior nasal aperture
42
Q

Common symptoms of cysts

A
  • Swelling (bluish if cyst expands beyond cortex, and results from their fluid content)
    Slow growth allows remodelling of bone but as cyst enlarges the bone things and continued resorption can lead to thin layer or reactive, woven bone around cyst and palpation of this => eggshell crackling
    Once it perforates the bone, allows palpation of fluctuance of cyst
  • missing/displaced/loose/un-erupted teeth or resorption of roots
  • about 1/3 get infected and may cause pain
  • pus can discharge (spontaneous, on xla or rct)
43
Q

How do vitality tests help with diagnosis of cysts

A
  • radicular cysts are associated with non-vital teeth

- discoloured tooth/history of trauma/sinus abscess

44
Q

How does radiography tests help with diagnosis of cysts

A
  • Cyst is a well defined, round radiolucency with corticated (white) margin
  • Check for associations such as with radicular cyst (necrotic tooth/carious tooth/root resorption) and dentigerous cyst (unerupted 8 or 3 attached to CEJ)
  • Consider CBCT
45
Q

How to systemically assess a radiograph when looking at cysts?

A
  • site
  • size
  • shape - unilocular/multilocular
  • outline - well defined? corticated? smooth?
  • relative radiodensity - radiolucent? uniform?
  • effect on adjacent structure - displacement, resorption, expansion
  • time present
46
Q

Difference between cyst and antrum?

A
  • both epithelial lined cavities and narrow cortical bone layer
  • may both be associated with non-vital tooth
  • wall of cyst not concave
  • check symmetry (e.g. Y line of Ennis - antrum should be symmetrical)
  • Needle aspiration/fluid injection
47
Q

What biopsies can be done to help diagnose cysts?

A
  • excisional biopsy of cyst is effectively definitive tx i.e. cyst enucleation and specimen sent to histopathology
  • odontogenic keratocyst have diagnostic appearance
  • if appearance is not typical of cyst, consider aspiration and incisional biopsy to exclude tumour
48
Q

How can aspiration of cyst help with diagnosis

A
  • Rarely done - may not be possible if bone hasn’t resorbed
  • Fluid filled cavity rules out granuloma/tumour (solid) or maxillary sinus (air)
  • straw coloured fluid and shimmering due to cholesterol
  • creamy viscous fluid is from keratin from odontogenic keratocyst (radicular and dentigerous cysts do not contain keratin)
49
Q

Signs of suspicion of cysts?

A
  • Recent onset
  • Fast growing
  • Neuropathy
  • Resorption of adjacent structures
  • Lack of response to antibiotics or RCT
50
Q

Standard treatment for radicular cysts

A
  • RCT of non-vital tooth will enable small probable cysts to regress (therefore first line of tx), if larger cyst then enucleation as well
  • Apicectomy + retrograde root filling + cyst enucleation if initial RCT unsuccessful
  • Extraction of non-vital tooth +/- enucleation of cyst
51
Q

Standard treatment for collateral cysts

A

enucleation and the tooth can be conserved

52
Q

Standard treatment for dentigerous cysts

A
  • Enucleation and extraction (8)

- Or marsupialisation and allow eruption of tooth (3 - orthodontic traction?)

53
Q

Standard treatment for odontogenic keratocyst

A
  • Check for signs of Basal Cell Naevus syndrome
  • Simple enucleation = recurrence between 25-60%
  • Difficult to enucleate in one piece due to satellite cysts
  • Consider peripheral ostectomy or Carnoy’s solution
54
Q

Steps of Enucleation and possible adjuncts?

A
  • removal of complete cyst including epithelial and capsular layers from bony walls and cavity
    1. mucoperiosteal flap is raised (buccal or palatal)
    2. remove window of cortical bone
    3. cyst peeled off bony cavity
    4. cyst lining likely to be breached releasing cyst contents
    5. area flushed with saline
  • Possible adjuncts are curettage, peripheral ostectomy, carnoy’s solution (enables cyst to be peeled away more easily but can cause nerve damage)
55
Q

Types of cyst excision and possible adjuncts?

A
  • Wide local excision removes lesion with margin of surrounding normal bone
  • En Bloc Resection removes a portion of structure with tumour with possible associated lymph nodes
  • Possible adjuncts are chemotherapy, radiotherapy and reconstructive surgery
56
Q

Steps of decompression of cyst

A
  • Aim of decompression is to reduce size of cyst prior to enucleation by relieving this pressure within the cyst
  • a small opening is made and a drain is inserted to keep it patent
  • subsequent enucleation is usually needed
57
Q

Steps of marsupialisation of cyst

A
  • Cyst is opened to oral cavity by excision of soft tissue overlying cyst (which is sent to histopathology) and edges are sutured to the margin of the cyst to keep it open and allowing decompression
  • Healing/reduction in size of cyst by bone deposition in base of cavity
  • Commonly resolves without the need for subsequent enucleation
  • Open cavity requires packing with gauze

Oral Disease (43 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions