OMFS Flashcards
What are the signs and symptoms of maxillary fracture?
Mobility of maxilla
Pain
Epitaxis
Numbness
Occlusal changes
Bony step formation
What are the LeFort Classifications?
Lefort- must involve pterygoid plates
1- Teeth and palate mobile
2- Involves nose mobility (into medial orbit)
3- Involves orbit mobility- all nasal bones and orbital bones included
What special investigations are used for fractures of the maxilla?
Occipitomental radiograph- 15 and 30 degrees
How is fracture of the maxilla managed
Closed reduction +/- fixation
Open reduction with internal fixation
What are the signs of a zygomatic-orbital fracture?
Facial asymmetry
Numbness in face
Pain
Difficulty moving eye
Restriction of looking up
Subconjucitval haemorrhage
Periorbital echymosis
Limited mouth opening
What radiographic views are requested for zygomatic-orbital fracture?
Occipitomental- 15 and 30 degrees
What are the treatment options for a zygomatico-orbital fracture?
Conservative management
ORIF
Closed reduction +/- fixation
What post operative advice is given to patients with zygomatic-orbital fracture?
Avoid nose blowing
Pain manangement advice
What are the signs and symptoms of mandibular fracture?
Limited opening
Occlusal derangement
Bleeding- sublingual haematoma
Asymmetry
AOB
Step deformity
- Involvement of soft tissue- simple/compound/comminuted
- Number- single, double, multiple
- Side- unilateral, bilateral
- Site
- Direction of fracture line- favourable or unfavourable
- Displacement
What radiographic views are used for mandibular fracture?
If plain (2 at right angles)- OPT and PA mandible
CBCT
How is mandibular fracture managed?
Control pain and infection- NSAIDs and ABs
If undisplaced- no tx
If displaced- closed with IMF or ORIF
What is a cyst?
A pathological cavity having fluid, semi-fluid or gaseous contents & which is not created by the accumulation of pus
What are the inflammatory cysts?
Odontogenic:
Radiciular cyst (and residual)
Inflammatory collateral cyst
-> Paradental
-> Buccal bifurcation cyst
What are the developmental cysts?
Odontogenic:
Dentingerous (eruption) cyst
Odontogenic keratocyst
Lateral periodontal cyst
NO:
Nasopalatine duct cyst
What are the treatment options for Cysts?
Enucleation
Marsupialisation
What are the advantages of enucleation?
Whole lining can be examined pathologically
Primary closure
Little aftercare needed
What are the disadvantages of enucleation?
- Risk of mandibular fracture with very large cysts
- (Dentigerous cyst) wish to preserve tooth
- Old age/ill health- can’t be put under GA
- Clot-filled cavity may become infected
- Incomplete removal of lining may lead to recurrence
- Damage to adjacent structures
- Daughter cysts in the keratocyst lining – to remove all of these would cause damage to adjacent structures/anatomy (have to use marsupialisation)
What are the advantages of marsupialisation?
Simple to perform
Spares vital structures
What are the disadvantages of marsupialisation?
- Opening may close & cyst may reform
- Complete lining not available for histology
- Difficult to keep clean & lots of aftercare needed
- Long time to fill in
Where does an odontogenic keratocyst develop from?
Rests of Serres
How does an OK appear histologically?
Daughter/sateillite cysts (if these are left they will form a new cyst)
Parakeratinised pithelial lining
No rete pegs in epithelium
Basal palisading- basal cells at same height
Evidence of multicentric growth with finger like projections
Cavity- wavey appearance
How does an OK appear radiographically?
Well defined
Scalloped margins
Often multilocular
Often cause displacement of adjacent teeth
Root resorption is uncommon
What are the issues with OK?
Late presentation- grows mesially-distally then starts to displace cortical bone/teeth
Recurrence- daughter cells
What condition is associated with OK?
Gorlin-Goltz syndrome
What does a radicular cyst develop from?
Epithelial rests of mallasez
What are the histological features of Radicular cysts?
Connective tissue capsule
Epithelial lining- NK stratified squamous
Cholesterol clefts
Hyaline/rushton bodies
Mucous metaplasia
Inflammation
How does a radicular cyst appear radiographically?
Round/oval
Well-defined
Coricated- margin continuous with lamina dura of non-vital tooth
Larger lesions may displace adjacent structures
Long standing lesions
-> External root resorption
-> dystrophic calcification
Where does a dentigerous cyst develop from?
Reduced enamel epithelium
How do dentigerous cysts appear histologically?
Thin NK Stratified squamous epithelium lining
-> attached to ACJ of unerupted tooth
May look like radicular cyst if inflamed
How do dentigerous cysts appear radiographically?
Corticated margins attached to cemento-enamel junctionoftooth
Larger cysts may begin to envelope root of tooth
Initially symmetrical- may expand unilaterally as it gets larger
May be evidence of displacement of involved tooth and cortical bone
Where are dentigerous cysts most commonly seen?
Unreupted:
Mandibular 8s
Maxillary 3s
What are the epithelial derived odontogenic tumours?
Ameloblastoma
Adenomatoid Odontogenic Tumour
Calcifying Epithelial Odontogenic Tumour
What are the histological features of Ameloblastoma?
- Islands present within fibrous tissue background, bordered by cells resembling ameloblasts (columnar cells, dark stained nucleus)
Follicular:
Tissue in middle of follicles- loose tissue similar to stellate reticulum (may be cystic changes or squamous metaplasia within follicles)
Plexiform:
- Similar to follicular but different arrangement
- Ameloblast like cells arranged in strands with stellate reticulum like tissue between
- Fibrous tissue support
What is a mixed epithelium and mesenchyme tumour?
Odontoma
What is a mesenchyme tumour?
Odontogenic myxoma
What are the indications for orthognathic surgery?
Fully grown
Functional and aesthetic issues- mental health impact
Severe skeletal discrepancy
What are the risks of orthognathic surgery?
Pain
Nerve damage
Bleeding
Infection
Relapse
What special investigations are done for orthognathic surgery?
Radiographs
Study models
Photographs- 2D/3D
What are the types of mandibular surgery?
Saggital split
Genioplasty
Vertical sub-sigmoid osteotomy
What are the types of maxillary surgery?
Le Fort 1
Anterior maxillary osteotomy
