Flashcards in 10.13.16 Deep Face Deck (58):
What are the bones of the temporal fossa?
3. Sphenoid (greater wing)
4. Frontal (very small portion)
Where do the temporal and infratemporal fossae communicate?
Inferiorly, at the zygomatic arch
What is the pterion?
Junction of parietal, temporal, sphenoid, and frontal bones
What does the middle meningeal artery supply?
Meninges and skull
The middle meningeal artery runs deep to the ___ and is particularly vulnerable to injury in this region.
What causes an epidural hematoma?
Rupture to the middle meningeal artery
What is the origin of temporalis?
Floor of temporal fossa, deep temporal fascia
What is the insertion of temporalis?
Coronoid process and ramus of mandible
What innervates temporalis?
Mandibular nerve (CN V3), deep temporal nerves
What supplies temporalis?
Superficial temporal artery, maxillary artery, middle, anterior, and deep temporal arteries
What is the function of temporalis?
Elevates mandible; posterior fibers retrude mandible
What is the origin of masseter?
What is the insertion of masseter?
Ramus of mandible, coronoid process
What innervates masseter?
Mandibular nerve (CN V3) via masseteric nerve
What is the function of masseter?
Elevates and protrudes mandible; deep fibers retrude it
What is the shape of the infratemporal fossa?
The infratemporal fossa is located ___ to the temporal fossa.
What is located in the medial superior border of the infratemporal fossa?
The infratemporal crest
What are the boundaries of the infratemporal fossa (superior, inferior, anterior, posterior, medial, lateral)?
1. Superior: zygomatic arch
2. Inferior: mainly the posterior aspect of submandibular region
3. Anterior: maxilla and inferior orbital fissure
4. Posterior: external auditory meatus, small portion of the SCM, styloid process, internal carotid artery, internal jugular vein, condyle of the mandible, deep lobe of the parotid gland
5. Lateral: ramus of the mandible, zygomatic process of temporal bone and zygomatic bone (temporal process)
6. Medial: lateral pterygoid plate and pharyngeal musculature
Superomedially, the roof of the infratemporal fossa is formed partially by the inferior surfaces of the greater wing of the ___ and the ___ bone.
What is contained superomedially in the infratemporal fossa?
Foramen ovale (V3), foramen spinosum (middle meningeal artery), petrotympanic fissure (chorda tympani nerve)
What does the anterior wall of the infratemporal fossa contain?
Alveolar foarmen, upper part opens as the infra-orbital fissure leading to the orbit
What does the lateral wall of the infratemporal fossa contain?
Mandibular foramen (inferior alveolar nerve and artery)
What does the medial wall of the infratemporal fossa contain?
Pterygomaxillary fissure in its anterior aspect which allows structures to pass first to the pterygopalatine fossa and then to the nasal cavity via sphenoplatine foramen
What are the contents of the infratemporal fossa?
1. Medial and lateral pterygoid muscles
2. Maxillary artery and its branches
3. Mandibular division of the trigeminal nerve and its branches
4. Sensory and motor branches of the facial nerve - chorda tympani
5. Branches of the glossopharyngeal nerve which synapse in the otic ganglion
6. Inferior portion of the temporalis muscle
7. Temporomandibular joint (TMJ)
8. Spheromandibular and stylomandibbular ligaments
9. Pterygoid plexus of veins
What are the four muscles of mastication?
Medial pterygoid, lateral pterygoid, masster, temporalis
What is the origin of lateral pterygoid?
Superior head: infratemporal surface of greater wing of sphenoid
Inferior head: lateral pterygoid plate
What is the insertion of lateral pterygoid?
Pterygoid fovea, capsule of TMJ, articular disc
What innervates lateral pterygoid?
Mandibular nerve (CN V3) - muscular branches from anterior division
What supplies lateral pterygoid?
Maxillary artery (muscular branches)
What is the function of lateral pterygoid?
Bilaterally: protrude mandible
Unilaterally and alternately: side-to-side grinding
What is the origin of medial pterygoid?
Medial surface of lateral plate of pterygoid, pyramidal process of palatine bone, maxillary tuberosity
What is the insertion of medial pterygoid?
Medial surface of ramus and angle of mandible inferior to mandibular foramen
What innervates medial pterygoid?
Mandibular nerve (CN V3) - nerve to medial pterygoid
What supplies medial pterygoid?
Facial artery and maxillary artery
What is the function of medial pterygoid?
Bilaterally: protrude and elevate mandible
Unilaterally and alternately: produces side-to-side movements
What protracts the jaw?
Lateral pterygoid (most important), medial pterygoid, masseter (limited)
What retracts the jaw?
Temporalis (posterior fibers), masseter (deep fibers)
What elevates (closes) jaw?
Temporalis, masseter, medial pterygoid
What depresses (opens) jaw?
Lateral pterygoid, digastric (primary anterior belly), mylohyoid, geniohyoid, infrahyoid, and gravity
What laterally displaces jaw (grinding and chewing)?
Ipsilateral masseter and temporalis, contralateral medial and later pterygoids
During lateral displacement, do the muscles of mastication act at once or in a series?
In a series
All the muscles acting on the mandible directly or indirectly influence the function of the ___.
Temporomandibular joint (TMJ)
What is the clinical manifestation of TMJ dysfunction?
Headaches, dizziness, "ear popping," and jaw pain
What type of joint is TMJ?
Synovial (diarthrodial), modified hinge joint (composed of right and left ellipsoidal joints forming a bicondylar articulation)
Unlike other synovial joints, TMJ does not contain the usual hyaline cartilage. Instead, what does it contain?
Dense irregular connective tissue articular disc
Each TMJ is divided into a superior and inferior compartment by its articular disc. Each part is a separate functional unit with its own special movement. Describe these.
1st movement: lower compartment (hinge movement - rotational - occurs first, opens jaw 1 finger breadth)
Second movement: upper compartment (sliding/gliding movement, opens jaw fully)
The articular disc of TMJ moves with the ___.
Head of the mandible
The ___ membrane of the joint capsule lines all non-articular surfaces of the upper and lower compartments of the joint, and attaches to the margins of the articular disc.
The ___ membrane of the joint capsule encloses the TMJ complex and is attached to the articular disc at its periphery to the inner aspect of this membrane.
The ___ artery is divided into three regional parts by the lateral pterygoid muscle.
What are the three regional parts of the maxillary artery?
1. Mandibular part
2. Pterygoid part
3. Pterygopalatine part
What are the branches of the maxillary artery?
1. Mandibular part:
-Middle meningeal artery
-Inferior alveolar artery
2. Pterygoid part
-Deep temporal artery (anterior and posterior)
3. Pterygopalatine part
-Posterior superior alveolar artery
The mandibular division of the trigeminal nerve (CN V3) is a ___ nerve carrying both motor and sensory fibers.
The mandibular division of CN V exits the middle cranial fossa via what foramen to enter the infratemporal fossa?
The anterior division of the mandibular division of the trigeminal nerve is primarily ___; the posterior division is primarily ___.
What are the anterior divisions of the mandibular division of the trigeminal nerve?
1. Buccal nerve (sensory)
2. Anterior and posterior deep temporal nerves
3. Nerve to the lateral pterygoid muscle
4. Nerve to the masseter muscle