Oral surgery Flashcards
Zygomatic fractures: key goals of treatment
- Restoration of facial projection/symmetry
- Restoration of orbital volume/globe position/shape of palpebral fissure.
Why might oral surgeons delay immediate treatment of facial fractures?
To allow
Reduction of facial odema/swelling
Reduction of conjunctival chemosis (eye swelling)
(delay it to allow observation of true anatomy and better surgical access)
Why might fracture that are treated TOO late (i.e. delayed) may also be disadvantageous?
Bony union incorrectly may have occurred over this time which will need to be surgically repositioned and this poses issues.
Zygomatic fractures: low energy vs high energy
Comminution (i.e. multiple fragments) seen in high energy impact fractures and minimally/not at all in low energy impact fractures.
What is this (in blue)?
Zygomaticosphenoidal suture
(a reliable indicator of proper treatment when restored)
ORIF
Open reduction and internal fixation
(most common treatment for facial fractures)
Zygomatic fracture types (by displacement and fragments)
- Non-displaced
- Displaced, minimally comminuted
- Complex and comminuted
- Isolated zygomatic arch fractures
Treatment of non-displaced zygomatic fracture
NON-surgical management
Must be confirmed by a CT scan, multiple observations (closely watching healing), prescribe a soft diet, analgesics.
Treatment of displaced, minimally comminuted fracture of zygomatic.
- Reduction alone (risk of displacement).
- Fixation (at one point or multiple, depending on injury type).
What is the zygomaticomaxillary buttress?
Where is the frontozygomatic suture?
Where is the frontozygomatic suture?
Treatment of displaced, minimally comminuted fractures best managed by reduction with direct visualisation at the ____ (3)
- frontozygomatic suture
- zygomaticmaxillary buttress
- inferior orbital areas
What are some of the advantages of ORIF?
Improved alignment
Fixation of zygomaxillary buttress provides vertical support
Orbital rim exposure allows inspection of orbital floor
Inspection of fractures sites prior to closure
What indication may require orbital floor exploration?
- Defects larger than 5mm on CT scan
- Severe displacement
- Comminution
- Soft tissue entrapment with limited upward gaze (in the bone)
- Orbital contents herniation into maxillary sinus
What features may require reconstruction of the orbits?
- Enophthalmos (globe is sunken in)
- Larger defects (5-10mm)
- Defects posterior to the axis of the globe
What zygomatic fracture would indicate THREE point fixation?
Instability
Exploration of orbital floor required
Most commonly used fixation method?
Mini plates and screws
(titanium)
resorpable plates and screws for tx of zygomatic fractures
Less commonly used due to price
Percutaneous bone hook
A method of reduction, this could be done from outside the mouth but also intro-orally.
Gillies temporal approachmethod
Incision 2cm in hairline (MUST AVOID superficial temporal artery)
Reduction method via temporal incision to provide traction to the zygomatic bone and reposition it.
Why are some zygomatic fractures known as “W” fractures?
Gillies temporal instruments
Bristol and Rowe
When placing three point fixation, what may also be placed in addition for a zygomatic fracture?
Repair and grafting plate onto the orbital floor.
Superior orbital fissure syndrome
SOFS - compression of the structures passing through the superior orbital fissures
very rare complication of zygomatic fractures (0.3-0.8%)
Diagnosis based on nerve involvement (challenges in eye movement), ptosis, fixed dilated pupil (mydriasis), loss of accomodation (eye cannot focus), anaesthesia of the upper eyelid/forehead.
Retrobulbar Haemorrahage with Orbital Compartment Syndrome
Very rare complication from facial fracture (1%)
Arterial bleed, rapid increase in volume/pressure —> pushing the globe forward
Can cause permanent loss of vision.
Note the “pushed forwards, but also pushed backwards” appearance.
What are midface fractures most commonly associated with?
High energy impact forces
RTAs
Severe assaults (weapons)
Falls from height
What are the three horizontal buttress?
Frontal
Zygomatic
Maxillary
What the three vertical buttresses?
- Nasomaxillary
- Zygomaticomaxillary
- Pterygomaxillary
What are the sagittal buttresses?
Zygomatic arches
Palate
Floor of the orbit
What bones are least resistant to horizontal impacts?
Nasal bones (least)
Zygomatic arch
Maxillae
What should the angle be of the mid-face?
What are some of the results of mid face fractures?
Anterior open bites
Facial lengthening
Soft palate obstruction to airway (EXTREME!!)
Nares blood clot (if conscious = ok)
Dish face deformity in severe cases (face looks like a dish = “concave”)
A - Le Fort III
B - Le Fort II
C - Le Fort I
Why might le fort I fractures result in an anterior open bite?
Due to the lateral and medial pterygoid muscles to the pterygoid plate and maxillary tuberosity, there is a tendency to pull the maxillary segment posteriorly and inferiority —> sometimes causing this open bite.
Horizontal fracture through the maxilla, separating the teeth and hard palate from the rest of the face. Involves the nasal floor, lateral maxillary walls, and lower part of the pterygoid plates.
Le Fort I
Pyramidal fracture involving the maxilla, nasal bones, inferior orbital rims, and medial orbital walls. Extends to the lacrimal bones and pterygoid plates.
Le Fort II
Craniofacial disjunction, separating the entire facial skeleton. Fracture involves the zygomatic arches, lateral orbital walls, orbital floors, nasal bones, ethmoid, and sphenoid.
Le Fort III
What should initial management for all facial fractures be?
Airway management
Haemorrhage
Head injury/GCS (Glasgow Coma Scale)
Secondary survey
Tamponade
Pressure caused by build up of fluid from haemorrhage — managed by nasal packing or ballon tamponade
Glasgow Coma Scale
Eye response
Verbal response
Motor response
1 being worse —> 4/6
score 3-15
Ecchymosis
Bruising (bleeding into the subcutaneous tissues)
What percussion note could you hear from the upper teeth Le Fort I?
“Cracked-pot” percussion note from upper teeth — more dull than what is expected.
What might you find clinically upon examination of a patient with an Le Fort I fracture?
Mobility of the tooth-bearing segment of the maxilla
What might you find upon clinical examination of a Fort II/III fracture?
“panda eyes” bilateral peri-orbital bruising
Facial lengthening
Malocclusion (AOB)
Gross oedema of face
Epistaxis
Mobility of maxilla
palatal haematoma
How would you mobilise a Le Fort II vs III fracture?
Fort II - inferior orbital rim
Fort III - Frontozygomatic sutures
How would you image Le Fort fractures?
CT scan
aids 3D visualisation and thus reconstruction
Unique fracture lines: Le Fort I
Lateral piriform aperture
Unique fracture lines: Le Fort II
Inferior orbital rim and zygomatic buttress
Unique fracture lines: Le Fort III
Lateral orbital wall & Zygomatic arch
What fracture type is this?
Le Fort II
What type of fracture is this?
Le Fort I
Facial fractures key aims with management
Restoration of normal function
Ocular
Nasal
Oral
Dental
Aesthetics
- Symmetry
What forceps are used to reduce facial fractures during surgery?
Roses disimpaction forceps
What type of fracture is this and which buttresses have been fixed?
Le Fort I
Nasomaxillary
Zygomaticomaxillary
What type of fracture is this and which buttresses have been fixed?
Le Fort II
Infra-orbital
Naso-Frontal
Zygomaticomaxillary
What type of fracture is this and which buttresses have been fixed?
Frontozygomatic
Naso-Frontal
Zygomatic arches
What are the most common type of facial fracture?
- Nasal fracture
- Mandibular fractures
Where is the most common place to get a fracture in the mandible?
- Condylar - 29.1%
- Angle - 24.5%
- Symphysis - 22%
These percentages change with age, as do the specific types of fractures seen between paediatric and adult mandibles and dentate and edentulous mandibles.
The symphysis/parasymphysis region of the mandible…
What is the main cause of mandibular fracture?
Assault (in the developed world)
RTAs (in the developing world)
Mandibular fracture type: radiographically can see the fractures but the bones haven’t been displaced?
Simple
Mandibular fracture type
Compound
- Perforation through the overlying periosteum (and maybe even skin).
- Any fracture that involves a tooth socket as this will run through the periodontium.
- Higher risk of wound infection due to exposure to the environment,
Mandibular fracture type
Comminuted
- Multiple fracture lines
- More high impact fractures (RTA and bullet wounds)
- Harder to manage
Mandibular fracture type
Green stick —> seen in paeds.
Many fractures in young patients are incomplete (greenstick) because of bones’ elasticity, allowing them to bend rather than break.