Infratemporal Fossa Flashcards
What are the boundaries of the Infratemporal fossa
- Lateral - ramus of mandible
- Medial - lateral pterygoid plate
- Anterior - posterior aspect of maxilla
- Posterier - TMJ
- Superior - Inferior surface of sphenoid
- Inferior - attachment of medial pterygoid to angle of mandible
What are the contents of the Infratemporal fossal
- Muscles - Inferior temporalis, lateral and medial pterygoid
- Vasculature - Maxillary artery, pterygoid venous plexus, maxillary vein
- Nerves - mandibular nerve and branches, PSA nerve, chorda tympani, otic ganglion
What muscle has head which inserts into the TMJ capsule and disc, as well as a head inserting into the neck of the mandibular condyle
- Lateral pterygoid
Nerve supply for Lateral Pterygoid:
Lateral pterygoid branch of V3
Blood supply for lateral pterygoid muscle:
Pterygoid branch of maxillary artery
Lateral pterygoid action (3):
Open mouth, protrude mandible, and deviate to opposite side
What muscle has a head (one of two) that originates at the maxillary tuberosity and inserts into the angle of mandible medially
Medial pterygoid muscle
Nerve supply and blood supply for medial pterygoid muscle:
- Nerve supply - medial pterygoid branch of V3
- Blood supply - pterygoid branch of maxillary artery
Action of Medial pterygoid muscle:
Elevate the mandible
Where is the pterygoid venous plexus located?
What is important about it?
Infratermporal fossa. It has no valves so blood flow bidirectional. Communicates with cavernous sinus.
The inferior dental alveolar nerve originates from the posterior division of the mandibular nerve. What branches off just before entry into the mandibular foramen?
Mylohyoid branch
Where does the lingual nerve lie in relation to the interior dental alveolar nerve?
Anterior. Runs down medial wall of mandible close to third molar, whilst IDN is within the bone.
The infratemporal fossa has a lot of communications with the orbit, temporal fossa, cranial space (through foramina), pterygomandibular space and pterygopalatine fosa. What is the clinical relevance of this?
In health individuals these communication zones are filled with loose areolar tissue, but in pathological conditions these are pathways of least resistance.
What is the name of the space within the infratemporal fossa where the IDB and lingual nerves are blocked
Pterygomandibular space
List 5 landmarks for IDB
- Coronoid notch
- Pterygomandibular raphe
- Mandibular premolar teeth on opposite side
- Mandibular occlusla plane
- Posterior border of mandible
The veins of the pterygoid venous plexus can be damaged during local to extract upper molar teeth. What can this result in:
Haematoma and trismus
You give an LA and the skin blanches. Why?
You’ve injected into the Maxillary artery leading to the facial artery branch.
Can cause temporary blanching, burning sensation or ocular complications.
Is the pterygoid plexus more likely to be damaged during upper or lower tooth treatment?
Upper.
5 clinical features of infratemporal fossa infection
- Severe pain
- Swelling of the face
- Trismus
- Difficulty swallowing
- Fever
Can happen as a result of spread of infection from upper wisdom teeth, upward spread from pterygomandibular space, or injured pterygoid plexus during local resulting in abscess and haematoma
What is Frey’s Syndrome?
Where auriculotemporal nerve has been damaged, and on repair the pathways cross over, so that when a person eats they sweat instead of salivate.
