Deep Face Flashcards
What is the pterion?
The H-shaped suture formed by the meeting of the parietal, frontal, sphenoid (greater wing) and temporal bones.
Why is the region of the pterion sensitive?
The middle meningeal artery runs deep to the pterion. Any injury to this artery can result in an epidural hematoma.
What is the weakest part of the skull?
The pterion.
Name the insertion of the temporalis.
Ramus of the mandible and coronoid process
Name the origin of the temporalis muscle.
Inferior temporal line and temporal fossa
What innervates the temporalis?
Mandibular division of the trigeminal nerve (V3) - anterior and posterior deep temporal nerves
What is the function of the temporalis?
Closes (elevates) and retracts the jaw
Blood supply of the temporalis?
Superficial temporal and maxillary arteries
Name the origin of the masseter.
The zygomatic arch
Name the insertion of the masseter.
Ramus of the mandible and coronoid process
What innervates the masseter?
Mandibular division of the trigeminal nerve (V3) - nerve to the masseter
Name the action of the masseter.
Powerfully closes (elevates) and retraction, and limited protraction of the jaw
What is the blood supply to the masseter?
Transverse facial artery
What are the most important features of the infratemporal fossa?
- Foramen Ovale (V3 entry)
- Foramen spinosum (middle meningeal artery enters)
- Petrotympanic fissure (chorda tympani enters)
- Opening to the mandibular canal (inferior alveolar nerve)
- Pterygomaxillary Fissure
What are the contents of the infratemporal fossa?
- The medial and lateral pterygoid muscles
- The maxillary artery and its branches
- The mandibular division of the trigeminal nerve [CN V3] and its branches
- Sensory and motor branches of the facial nerve [CN VII] - chorda tympani;
- Branches of the glossopharyngeal nerve [CN IX] which synapse in the otic ganglion (parasympathetics for parotid gland from CN IX)
Name the origins of the 2 heads of the Medial Pterygoid.
Medial head: medial surface of the lateral pterygoid plate.
Lateral head: lateral surface of the lateral pterygoid plate