Temporal Fossa Flashcards
What is included in the temporal region
Temporal and infratemporal fossae— superior and inferior to the zygomatic arch, respectively
Where is the temporalis muscle located?
Temporal fossa
What are the boundaries of the temporal fossa?
Post and superior: sup and inf temporal lines
Anterior: frontal and zygomatic bones
Lateral: zygomatic arch
Inferior: infratemporal crest
The floor of the temporal fossa is formed by what?
Parts of the 4 bones (frontal, parietal, temporal, and greater wing of the sphenoid) that form the pterion
What forms the roof of the temporal fossa?
Temporalis fascia, which extends from the superior temporal line to the zygomatic arch
Muscles of mastication acting on the mandible and temporomandibular joint
Temporalis
Masseter
Lateral pterygoid
Medial pterygoid
Attachment, innervation and action (ANA) of temporalis muscle
Proximal attachment: triangular muscle with broad attachment to floor of temporal fossa and deep surface of temporalis fascia
Distal attachment: Narrow attachment to tip and medial surface of coronoid process and anterior border of ramus of mandible
NS: deep temporal nerves that arise from the anterior trunk of mandibular nerve (CN V3)
Action on mandible: Ant vertical fibers elevate the mandible and close the jaws
- Post horizontal fibers retracts the mandible posteriorly
ANA for masseter (quadrate muscle)
Proximal attachment: Inf border and medial surface of zygomatic arch
Distal attachment: angle and lateral surface of ramus of the mandible
NS: masseteric branch- emerges from ant trunk of mandibular nerve
AC: elevated the mandible
ANA for lateral pterygoid (triangular)
Prox. Attachment: 2 heads
- infratemporal surface and crest of greater wing of sphenoid
- lateral surface of lateral pterygoid plate
Dist. Attachment: -sup. Head- joint capsule and articular disc of TMJ
-inf head- anteromedial aspect of neck of condyle of process of mandible
NS: Nerves to lateral pterygoid (from ant trunk of mandibular nerve)
AC: Bilateral: protracts mandible and depresses chin
Unilaterally: swings jaw toward contralateral side
Alternate unilateral contraction— producers larger lateral chewing movements
ANA for medial pterygoid (quadrangular)
Proximal attachment: 2 heads
- Medial surface of lateral pterygoid plate
- Tuberosity of maxilla
Distal: Medial surface of ramus of mandible- inf to mandibular foramen
NS: Nerve to medial pterygoid- from ant trunk of mandibular nerve
AC: -synergistic with masseter to elevate mandible
- Contributes to protrusion
- Alternate unilateral activity produces small grinding movements
What is the infratemporal fossa?
An irregularly shaped space deep and inferior to the zygomatic arch, deep to the ramus of the mandible, post to the maxilla
Boundaries of the infratemporal fossa
Laterally: ramus of mandible
Medially: lateral pterygoid plate
Ant: post aspect of the maxilla
Post: tympanic plate & mastoid and styloid processes of the temporal bone
Sup: inf. Surface of the greater wing of sphenoid bone
Inf: where medial pterygoid muscle attaches to the mandible near its angle
Contents of the infratemporal fossa
Inf part of the temporalis muscle
Lateral and medial pterygoid muscles
Maxillary artery (larger)
Pterygoid venous plexus
Mandibular, inf alveolar, lingual, buccal and chorda tympani nerves and the optic ganglion
What is the larger of the 2 terminal branches of the external carotid artery?
Maxillary art
The maxillary arty arises posterior to the:
It courses anteriorly deep of the:
Then passes superficial or deep to the:
Neck of mandible
Neck of the mandibular condyle
Lateral pterygoid
The maxillary artery passes medially from the _____ fossa through the _______ fissure to enter the:
Infratemporal
Preygomaxillary
Pterygopalatine fossa
The maxillary divides into ___ parts by its relation to the:
3
Lateral pterygoid muscle
Branches of the 1st part of the maxillary artery and what they supply
Middle meningeal artery- supplies dura mater and Calvaria
Inferior alveolar artery- supplies the mandible, gingivae, teeth and floor of the mouth
Branches of the 2nd part of the maxillary artery and what they supply
Deep temporal arteries- ant and post- ascend to supply the temporalis muscle
Pterygoid arteries- supply the pterygoid muscles (duh)
Masseteric art- passes laterally through the mandibular notch to supply the masseter muscle
Buccal art: supplies the buccinator muscle and mucosa of the cheek
Branches of the 3rd part of the maxillary artery (pterygopalatine)
Posterior superior alveolar art
Infra-orbital art
Descending palatine art
Pharyngeal art
Sphenopalatine art
What does the posterior superior alveolar art supply
Maxillary molar and premolars teeth
Buccal gingiva
Lining of the maxillary sinus
What does the infra-orbital art supply?
The inf eyelid, lacrimal sac, infra-orbital region of the face, side of the nose and the upper lip
What does the descending palatine art supply
The mucous membrane and glands of the palate (roof of mouth) and palatine gingiva
What does the pharyngeal art supply
Roof of the pharynx, sphenoidal sinus, and inf part of the pharyngotympanic tube
What does the sphenopalatine art supply
Lateral nasal wall, nasal septum, and adjacent paranasal sinuses
What is the termination of the maxillary artery?
Sphenopalatine artery
What occupies most of the infratemporal fossa?
Pterygoid venous plexus
The pterygoid venous plexus is located partly between the ______ and _____ muscles
Temporalis
Pterygoid
What does the pterygoid venous plexus drain into?
Anteriorly to the facial vein via deep facial vein
Mainly drains posteriorly via the maxillary and then the retromandibular veins
The mandibular nerve receives the motor root of the _____ nerve and descends through the ____ _____ to enter the ______ fossa, dividing into:
Trigeminal nerve (CN V)
Foramen ovale
Infratemporal fossa
Anterior and posterior trunks
The posterior division of the mandibular nerve gives what branches?
Auriculotemporal nerve
Inf. Alveolar nerve
Lingual nerve
Chorda tympani nerve
The auriculotemporal nerve arises by two roots that encircle the _____ ____ artery and then:
Middle meningeal artery
Unite into a single trunk
The auriculotemporal nerve pathway
Passes posteriorly, medial to the neck of the mandible
What does the auriculotemporal nerve supply
Auricle and temporal region
TMJ
Parasympathetic secretomotor fibers to the parotid gland
The inf alveolar nerve enters the _____ foramen and passes through the _____ ____, forming the ____ ____ ___.
Mandibular
Mandibular canal
Inferior dental plexus
What that the inf. Alveolar nerve supply
Mandibular teeth
The inf alveolar nerve gives what branches?
Nerve to mylohyoid- arises just before entering the mandibular foramen
Mental nerve
The mental nerve passes through the ____ foramen and supplies the:
Mental
Skin and mucous membrane of the Lower lip
The lingual nerve lies:
It enters the mouth between:
And passes:
Anterior to the inf alveolar nerve
The medial pterygoid and Ramus of mandible
Just inferior to the 3rd molar tooth
The lingual nerve supplies:
Sensory to the anterior 2/3rds of the tongue
Floor of the mouth
Lingual gingivae
The chorda tympani nerve joins the _____ nerve in the ____ fossa
Lingual
Infratemporal
What is the function of the chorda tympani nerve
Carries taste fibers from the anterior 2/3 of the tongue and presynaptic secretomotor fibers for the submandibular and sublingual salivary glands
What type of joint is the TMJ?
Modified hinge type of synovial joint, permitting movement in 2 planes
Articular surface of the TMJ
Head of the mandible
Auricular tubercle of the temporal bone
Mandibular fossa
The articular surfaces of the TMJ are covered by _____
Fibrocartilage
What divides the TMJ joint cavity into 2 separate synovial compartments?
Articular disc
Joint capsule of the TMJ is (TIGHT/LOOSE). The thick part of it forms the:
Loose
Intrinsic lateral ligament (temporomandicular ligament)
What are the 3 extrinsic ligaments that connect the mandible to the cranium?
Lateral ligament (temporomandibular ligament)
Stylomandibular ligament
Sphenomandibular ligament
The stylomandibular ligament is a thinking of the ____ ____ of the ___ ___.
It runs from the ____ ____ to the:
Fibrous capsule
Parotid gland
Styloid process
Angle of the mandible
The sphenomandibular ligament runs from the __________ to the:
Spine of the sphenoid
Lingual of the mandible
Movements of the temporomandibular joint
Elevation (close mouth)
Depression (open mouth)
Protrusion (protrude chin)
Retrusion (retried chin)
Lateral movements (grinding and chewing)
Elevation of the TMJ is produces by what muscles
Temporalis
Masseter
Medial pterygoid
Depression of the TMJ is done by what muscles
Lateral pterygoid
Suprahyoid
Infrahyoid
What muscles are responsible for retrusion of the TMJ
Temporalis (post. Oblique and near horizontal fibers)
Masseter
What muscles are responsible for lateral movements of the TMJ
Temporalis of same side
Pterygoid of opposite side
Masseter
Does the pterygoid venous plexus have valves?
No
-blood can flow in several directions depending on pressure conditions
What is the significance of blood flow in the pterygoid venous plexus
Bacteria from an infection of dental/oral origin can be carried from the infratemporal fossa to the cavernous sinus. Could result in meningitis or other intracranial infection
What is commonly used by dentists when treating mandibular teeth?
Inferior alveolar nerve block
What can cause dislocation of TMJ?
Sometimes during yawning or taking a large bite, excessive contraction of the lateral pterygoids may cause the heads of the mandibles to dislocate anteriorly, by passing anterior to the articular tubercles.
