Midfacial # Flashcards
What names are the midfacial # called?
Midface fractures
Middle 1/3rd
Le Fort type(s)
Panfacial: involving all the face
Complex
Major Facial Trauma
What is the aetiology of mid face fractures?
High energy
High impact forces
RTA
Severe assault weapons: a bat
Falls from height
Industrial
Agriculture
War injuries
What are mid facial fractures?
1- Complex subset of fractures
2- Disarticulation parts of upper facial skeleton from
Skull base/cranium
3-Potentially serious outcomes & associations:
>Airway
>Haemorrhage
>Head injury
>Orbital/eye injury
>Other trauma
How is the mid facial skeleton defined by anatomy, what are the three sections?
Defined by;
Superiorly;
Frontozygomatic
Frontonasal
Frontomaxillary
Inferiorly;
Occlusal plane upper teeth
Alveolar ridge (edentulous)
Posteriorly;
Pterygoid plates sphenoid
What bones is the mid face made of?
Formed from;
Two zygomatic bones
Two maxillae bones
Two zygomatic process Temporal bones
Two palatine bones
Two nasal bones
Two lacrimal bones
Vomer
Ethmoid (and attached conchae)
Two inferior conchae
Pterygoid plates of sphenoid
What system does the mid facial section have to protect its self and how does it achieve that?
the mid facial skeleton is bone and Air containing sinuses with are surrounded with Interrelated pillars or struts.
Stability via paired buttressing system;
Vertical
Horizontal
Sagittal
to allow Masticatory forces in the vertical system
this system would also allow Mid face collapse for Energy absorption and Protective of the face.
what is the horizontal butress system made of?
There are three, the frontal, zygomatic and the maxillary
1-Superior orbital rim
2- Inferior orbital rim
2- Zygomatic arches
3-Maxillary alveolus
3-Palate
3-Serrated edges greater wings of sphenoid into the sagittal buttress of the zygomatic arches
what is the vertical butress system made of? and what is its main aim?
1-Nasomaxillary: lateral preaform rim and maxillary process of the frontal bone and the frontal process of the maxilla
2- Zygomaticomaxillary: frontal bone to the lateral orbital wall
3-Pterygomaxillary: pterygoid plates of the sphenoid and the maxillary tuberosity which establishes the posterior facial height
Primarily masticatory- transmission to skull base.
what is the sagittal butress system made of
Zygomatic arches
Palate
Floor of orbit
What are physical characteristics of mid facial skeletal bones?
1-Multiple bones, rarely affected in isolation
2-Series of bone struts with function: Manage masticatory forces by distribution around fragile bones to base of skull to
Protect important structures
> Withstand considerable forces from below
Readily disrupted trivial forces directions other
i.e. 1/5th – 1/3rd cf forces to fracture Mandible
What are the lest resistant bones in the mid face region?
Nasal bones least resistant
Zygomatic arch directly
Maxillae – horizontal forces.
What features could we see in a mid facial # patient?
1- Anterior open bite *
2-Facial lengthening.
3-Extreme – soft palate obstruct airway.
4-Nares blood clot Conscious –ok .
5-Coincident head injury= danger until airway clear
6-Dish face deformity in severe
How would you describe Le Fort 1 #?
It is caused by a force above dentoalveolar segment
it includes the:
1- Lateral nose/piriform aperture
2- Anterior/lateral/inferior wall max sinus
3-Maxillary tuberosity
4- Palatal process of maxilla
5- Horizontal plates palatine bones
6-Lower parts of the pterygoid plates pterygomaxillary junction
7-Nasal Septum
8-Septal cartilage
> Horizontal maxillary fracture
Separating the teeth/Whole complex of alveolar
AKA Guerin fracture
Why does a LE Fort 1# cause an open bite?
Due to the muscle attachments of the pterygoid muscles to the plates and the pulling posteriorly and inferiorly when the # happens
How would you describe Le Fort 2 #?
it is caused by a Force (superior) directed at nasal bones:
Posterior alveolar ridge
Lateral walls of the maxillary sinuses
Inferior orbital rim
Nasal bones
Nasofrontal junction of the frontal process of the maxilla
Pyramidal fracture separates the whole maxilla with part of the nasal bones and the lower part of the pterygoid plates
Teeth at the pyramid base and Nasofrontal suture remnant apex
