Oral Surgery Flashcards
What is the definition of a cyst?
A cyst is a pathological cavity having fluid or semi-fluids contents, which has not been created by the accumulation of pus. These occur more commonly in the jaw bones than elsewhere and are often epithelial lined.
Why do cyst form more commonly in the jaw bones?
Because there are epithelial remnants left from the dental lamina here.
Specifically what developing dental tissues are responsible for forming cysts?
Cell rests of Malassez from root sheath of Hertwig that forms a root of the tooth - these for the radicular inflammatory cyst.
Reduced enamal epithelium also forms a lining over the crown of the tooth in the follicular tissue that form a dentigerous cyst.
What is the process that drives the expansion of a cyst?
Hydrostatic process.
What kind of swelling will be present intra-orally if a cyst is present?
Smooth/fluctuant swelling
Name 12 signs and symptoms of a cyst?
- Asymptomatic, chance finding on radiograph
- Bony expansion (egg shell crackling)
- Fluctuant swelling
- Missing teeth
- Carious, discoloured, fractured teeth
- Tilted/displaced teeth
- Discharge/sinus
- Loose teeth
- Mental hypoaesthesia
- Hollow percussion note
- Pain and swelling if secondary infection
- Pathological fracture
Name 4 investigations you could carry out if a cyst is suspected.
- Vitality testing of teeth around the cyst
- Radiographs - possibly include CBCT however firstly do periapicals/DPT if large
- Aspiration of cystic contents (if contents are clear then its often an inflammatory radicular cysts).
- Biopsy to establish it is a cyst.
What are 3 aims when managing mandibular cysts?
- Eradicate the pathology
- To minimise surgical damage
- To restore function quickly
State 6 treatment options for cysts.
- marsupialisation
- enucleation
- marsupialtion + enucletion
- enucleation and curettage/ excision
- en bloc resection-jaw continuity maintained
- partial resection-continuity lost
What is the first line treatment option?
Enucleation
What is enucleation?
Complete removal of the cyst lining. Following enucleation closure can be primarily or secondarily by packing defect. This may be contraindicated if the cyst is large, involving a number of vital teeth, in a difficult anatomical site or involving a potentially useful unerupted tooth.
What are the different stages surgically of the procedure of enucleation?
- Raise a flap- dont incise over the access site to the cyst
- Lift the mucosa off the bone
- Remove overlying buccal bone and curettage
- Suture the flap with the mucosa resting on crestal bone
- The space created after the cyst is removed will fill with blood and then turn into granulation tissue and eventually bone.
Why is having a dead space not beneficial?
- Can get reactionary haemorrhage
- Post operative infection
What can you do to eliminate the dead space?
- Place a drain, a vaccum drain will suck down the size of the dead space
- procedure to collapse the wall of the cavity
- Use of biological and other materials to fill the space.
- Use layered soft tissue closure or secondary intention (packing).
What are the advantages of enucleation?
- Complete removal for histology
- Cavity heals without complications
What are the disadvantages of enucleation?
- Infection
- Incomplete removal of lining
- Damages to adjacent teeth or antrum
- Weakening of bone
What is marsupialisation?
The creation of a window in the cyst lining, suturing the flap to the remaining lining to allow shrinkage of the lesion which may become self cleansing or be subsequently removed.
This is the treatment of choice in cases of eruption cysts involving potentially useful teeth.
What are the different stages surgically of the procedure of marsupialisation?
- Make an incision at the site of the cyst
- Raise mucoperiosteal flap so that you have superior and inferior aspects to the flap
- Do not suture, you want healing by granulation tissue, this area isnt self cleansing so you place an acrylic bung to prevent food debris entering
- Over several months bone will deposit underlying.
What are the advantages of marsupialisation?
- Avoids pathological fracture
- Treatment for medically compromised patients
- Avoids damage to adjacent structures
- Allows potentially useful teeth to erupt.
What are the disadvantages of marsupialisation?
- Orifice closes and cyst reforms
- Repeat visits
- Manual dexterity and compliance
- Complete lining not available for histology
What is a radicular cyst?
- Inflammatory in origin and associated with a non-vital tooth. 60% of all dental cysts. Involves the apex of the tooth. 20% can be residual cysts.
Name 2 other inflammatory cysts.
Collateral cysts e.g; buccal bifurcation cyst and paradental cyst.
List the first 5 most common odontogenic cysts in order.
Most common: Radicular cyst 60-75%
Dentigerous cyst 10-15%
Keratocyst 5-10%
Paradental cyst 3-5%
Least common: Gingival/lateral periodontal cyst <1%
Name the most common non-odontogenic cyst.
Nasopalatine cyst 5-10%
Approximately what % of cysts remain after the tooth is removed?
20%.
How would you typically treat a radicular cyst?
- Enucleation with either extraction of associated tooth or apiceptomy following endodontic treatment.
- This applies to lateral cysts and residual cyst.
- If a cyst is large and covering many teeth then can marsupialise first to shrink the cyst then enucleate.
Name 5 developmental cysts.
- Dentigerous cysts
- Eruption cyst
- Odontogenic keratocyst
- Lateral periodontal
- Gingival
How would you treat a dentigerous cyst?
- Enucleation with removal of associated tooth (wisdom teeth)
- Marsupialisation if unerupted tooth is potentially functional and can be aligned orthodontically (maxillary canines).
How would you treat an odontogenic keratocyst?
- Enucleation, paying particular attention to ensuring removal of an intact lining to reduce recurrence, and tooth removal
- Curettage of cavity (Carnoys solution)
- Long term radiographic follow up
- En bloc resection
Why is it particularly difficult to enucleate odontogenic keratocysts?
- Grow anterior-posterior direction in finger like projections so its difficult to remove in its entirety.
- Also contain daughter cells in the underlying bone therefore if you leave these then these can recur.
If a OPT showed root resorption of the teeth involved in a cyst like radiolucency then what would this suggest?
Suggest more likely an odontogenic tumour rather than cyst and would require a biopsy.
What is Gorlin-Goltz syndrome/Nevoid basal cell carcinoma syndrome?
Autosomal dominant genetic condition where theres multiple odontogenic keratocysts.
What are some signs and symptoms of a patient with Gorlin-Goltz syndrome?
- Multiple basal cell carcinomas of the skin
- Odontogenic keratocyst (seen in 75% of patients and this is the most common finding. Usually multiple lesions in the mandible). Occur at a young age e.g 19 years.
- Rib and vertebrae anomalies
- Intracranial calcification
- Skeletal abnormalities: bifid ribs, kyphoscoliosis
- Distinct facies: frontal and tempoparietal bossing, hypertelorism, and mandibular prognathism
- 3 or more palmer or plantar pits.
- first degree relative with this condition
How does lateral periodontal cyst/gingival differ from a radicular cyst and what is the treatment?
- Lateral periodontal cyst/gingival cyst will be vital whereas radicular wont… treatment is to enucleate
What are examples of non-odontogenic cysts and what kind of tissues do they arise from?
- Nasopalatine duct cyst
- Nasolabial cyst
Arise from the remnants of the fusion of embryonic arches that form the face.
If there is a radiographic heart shaped cyst on the anterior maxilla and the patient is having a salty taste what kind of cyst would this indicate?
Nasopalatine cyst
What is the treatment for nasopalatine cyst?
Enucleation after you establish the vital of anterior teeth (palatal flap raised)
What does a nasolabial cyst typically present as clincically and what is the treatment for this?
Patients will have fullness labially and cheeks and elevation of the base of the nose. Treatment is marsupialisation and enucleation.
What is Staphnes idiopathic bone cyst?
This is a developmental anomaly (not a cyst), ectopic salivary tissue in concavity in the medial aspect of the mandible. No active treatment is required as no pathology.
What are the 2 more common primary bone cysts?
- Aneurysmal bone cyst
- Solitary bone cyst
What causes an aneurysmal bone cyst and what is the treatment for this?
Unknown aetiology - can present as large blood filled radiolucencies. Contains giant cells.
Surgically expose this cyst and take a biopsy. You would curette the cyst at the same time which usually promotes healing therefore can treat at the same time as investigation.
What is the incidence of solitary bone cysts and what is the treatment?
Solitary bone cysts are large radiolucencies that arch up between roots of the teeth. Typically in teenagers in the mandible with F>M.
Resolve spontaneously.
What is the most common odontogenic tumour?
Ameloblastoma.
What is an ameloblastoma and what does look like on a radiograph?
- Odontogenic tumour arising from tooth forming structures
- Essentially benign but can be locally aggressive and invasive
- Uni or multilocular, defined or diffused edged, usually displaces adjacent structures.
- 40-50 years, 80% mandible.
- Need to biopsy.
What are the subtypes of ameloblastoma?
- luminal
- intraluminal
- mural
The first 2 subtypes can be treated conservatively but the one might need to be treated as ameloblastoma.
What is an adenoid ameloblastoma?
New entity added in the odontogenic lesions and it represents the most important change. It is defined as an epithelial odontogenic neoplasm composed of cribiform architecture and duct like structures and frequently includes dentinoid. Approximately 40 cases have been reported in the literature so far.
