Temporal and Infratemporal Fossa Flashcards
INFRATEMPORAL FOSSA BOUNDARIES Anterior Posterior Superior Inferior Lateral Medial
Anterior:
- Infratemporal Surface Maxilla
Posterior:
-Vertical Plane of Styloid Process (of Temporal Bone)
Superior:
- Infratemporal surface
- Crest of Greater Wing of Sphenoid
Inferior:
- Horizontal Plane of Alveolar Margin of the Mandible
Lateral:
- Ramus of Mandible
Medial:
- Lateral Pterygoid Plate
Fissures and Foramina of the Infratemporal Fossa
- Pterygomaxillary Fissure
- Mandibular Canal
- Foramen Ovale
- Foramen Spinosum
- Alveolar Canal
- Petrotympanic Fissure
What part of the temporal bone articulates with the mandible?
- what is the articulation called?
- Tympanic Part
- Form Temporomandibular join t
What is the supramastoid crest
- Posterior extension of the zygomatic arch above the mastoid
The groove for what artery can be found vertically oriented above the mastiod process?
- Groove for the middle temporal artery (branch of superficial temporal)
What features of the temporal bone are involved in making the temporomandibular joint?
- Anterior
- Posterior
- Superior
Anterior:
- Articular Tubercle (at bottom of zygomatic process)
Posterior:
- Tympanic part of the temporal bone (overlying the EAM)
Superior:
- Mandibular Fossa
What feature marks the division between the squamous and tympanic parts of the temporal bone?
- What passes through?
- Petrotympanic Fissure
- Chorda Tympani (on its way to the infratemporal fossa)
Foramen Ovale and Foramen Spinosum allow for passage of structures between what two spaces?
- What structures
Communication between:
- Middle Cranial Cavity
- Infratemporal Fossa
Structures:
- Middle Meningeal a. (spinosum)
- V3 (ovale)
- Lesser Petrosal - IX (ovale)
- Accessory Meningeal a. (ovale)
What bony structure is immediately medial to foramen spinosum?
- What attaches here?
- Spine of the Sphenoid
- Sphenomandibular Ligament attaches here
What are the anterior, posterior, and superior processes of the zygomatic bone?
- Anterior: Maxillary Process
- Posterior: Temporal Process
- Superior: Frontal Process
What muscle(s) attach(es) to the coronoid process?
- Temporalis muscle
What is the anterior border of the coronoid process continuous with anteriorly?
- Oblique line (on the lateral, exterior surface of mandible)
What is the name of the shallow depression on on the anterior surface of the neck of the mandible?
- What attaches here?
- Pterygoid Fovea
- Lateral Pterygoid Attaches here
What attaches to the lingula of the mandible?
- Sphenomandibular ligament
spans spine of sphenoid and lingula
What attaches to the roughened area on the medial side of the ramus of the mandible?
- Medial Pterygoid muscle
What two parts make up the TMJ, what divides TMJ into these two parts?
Articular Disk - Makes the division
Lower Part:
- Hing-like depression and Elevation
Upper part:
- Protrusion and Retraction
T or F: opening the mouth requires both depression and protursion
True
What 3 ligaments are associated with TMJ?
- Lateral Ligament (lateral)
- Sphenomanibular ligament (medial)
- Stylomandibular Ligament (posterior)
What structures does the stylomandibular ligament span?
- Styloid Process
- Posterior margin and angle of mandible
What mm. are involved in depression of the mandible?
Downward:
- Digastric
- Geniohyoid
- Mylohyoid
Forward:
1. Lateral Pterygoid mm.
What mm. are involved in elevating the mandible?
- Temporalis
- Masseter
- Medial Pterygoid
What mm. are involved in protraction of the mandible?
- Lateral Pterygoid
- some assistance of medial pterygoid
What mm. are involved in REtraction of the mandible?
- Geniohyoid
- Digastric
- Temporalis
- Massester
What is the innervation of all of the muscles used to move TMJ?
- exception?
- Branches of V3
Exception:
- Geniohyoid = C1 via hypoglossal
What nerve and artery supply the masseter?
Nerve:
- Massenteric n. (=> V3)
Artery:
- Massenteric a. (=> Maxillary a.)
What forms the medial and lateral floors of the temporal fossa?
Medial - continuous with infratemporal fossa
Lateral - Region containing masseter
T or F: the temporalis muscle also contributes to side to side movement of the mandible
True
What fossae/fissures are found in the roof of the infratemporal fossa?
- Foramen Spinosum
- Foramen Ovale
- Tympanic Fissure
What muscle runs between the two heads of the medial pterygoid muscle?
- LOWER head of the Lateral Pterygoid
What happens to your chin when you flex your medial and lateral pterygoid muscles only on one side?
- Chin moves to the opposite side
What is the only branch of the trigeminal that has motor function?
- Mandibular n. (V3)
* Maxillary (V2) and Opthalmic (V1) both are purely sensory
What does the motor part of V3 innervate?
Muscles of Mastication:
- Masseter
- Temporalis
- Medial Pterygoid
- Lateral Pterygoid
MATT:
- Mylohyoid
- Anterior Digastric
- Tensor Tympani
- Tensor Veli Palatini
V3 drops down between what two muscles to exit the middle cranial fossa to get to the infratemporal fossa?
Through Foramen Ovale btwn:
- Tensor Veli Palatini (Medial)
- Upper Head of lateral Pterygoid (lateral)
T or F: the motor branch of trigeminal must pass through the trigeminal gangion to exit the middle cranial cavity?
- False, it exits through foramen ovale after bypassing the ganglion, THEN joins the sensory nn.
What branches are given off of V3 BEFORE it splits into anterior and posterior trunks?
- N. to Medial Pterygoid
2. Small meningeal branch
What are the branches of the anterior trunk of trigeminal?
- Predominant function
Motor:
- N. to Lateral Pterygoid
- Masseteric n.
- Deep Temporal n.
Sensory:
1. Buccal n.
What are the branches of the Posterior trunk of trigeminal?
- Predominant function?
Sensory:
- Auriculotemporal n.
- Inferior Alveolar n.
- Lingual n.
Motor:
1. N. to mylohyoid
What is the course of the meningeal branch of V3?
- sensory or motor?
- to where/what?
- Trunk
- Branches from V3 BEFORE trunk division
- Reenters foramen Spinosum with Middle Meningeal a.
***Sensory to Dura Mater
What is innervated by the n. to medial pterygoid (V3 - NO trunk) ?
- Medial Pterygoid m.
- Tensor Veli Palatini
- Tensor tympani
What is the course of the buccal n. (Ant. Trunk - V3)?
- Passes BETWEEN upper and lower heads of the lateral pterygoid
- passes anteriorly and laterally to cheek LATERAL to buccinator m.
What is innervated by the buccal n. (Ant. Trunk - V3)?
GSA to:
- Cheek skin
- Oral mucosa (lower molars)
- Buccal Gingivae (lower molars)
What nerve passes through the mandibular notch?
- Trunk
- Massenteric n. (Ant. Trunk - V3)
What nerves supply the temporalis muscle?
- Trunk
- Deep Temporal n. (Ant. Trunk - V3)
What nerve innervates the lateral pterygoid m.?
- Trunk
- N. to Lateral Pterygoid (Ant. Trunk - V3)
What nerve comes off as two roots that spit around the middle meningeal a.?
- Trunk
- Ariculotemporal n. (Post. Trunk - V3)
Branches of what nerve travel where with auriculotemporal n. (Post. Trunk - V3)?
- POSTganglionic parasympathetic fibers TO PAROTID from glosspharyngeal (IX)
What nerve hitchhikes with lingual?
- Fiber type?
- Chorda Tympani (VII)
- GVE and SA
***COURSE OF LINGUAL N. INTO THE ORAL CAVITY
- Lateral to Medial across front of medial pterygoid
- BELOW Sup. Pharyngeal Constrictor but ABOVE mylohyoid m.
- travels IMMEDIATELY INFERIOR to the last molar tooth
***What nerve is at high risk when working on the posterior molars?
- LINGUAL n. it is JUST DEEP to the oral mucosa and is even palpable here
***What functions would be lost by cutting the lingual n.?
- GSA to tongue (2/3)
- Oral Mucosa on Floor of Oral cavity
- Lingual Gingiva of lower teeth
***Additionally, Salivation could be lost from submandibular and sublingual glands (if distal to chorda tympani)
What is supplied by the inferior alveolar n.?
- Lower Teeth and Gingivae
2. Mucosa and Skin of Lower Lip and Chin
What are the two terminal Branches of the inferior alveolar n.?
Incisive n.
Mental n.
What two CNs have branches that join V3 branches in the infratemporal fossa?
- Chorda Tympani (CN VII - SA/GVE)
2. Lesser Petrosal (CN IX - GVE)
***When trying to anesthetize the lingual n. where would you place the needle?
- Anterior and Lateral to the Palatoglossal arch and medial to the mandible
What common place to veins draining the infratemporal and pterygopalatine fossae go?
Pterygoid Plexus
Where does the maxillary artery originate?
- from external carotid INSIDE the parotid gland
What structures bound the 1st part of the maxillary a.?
- Neck of Mandible
2. Sphenomandibular Ligament
What stucture bounds the 2nd part of the maxillary a.?
- Lateral Pterygoid m.
Where is the 3rd part of the maxillary a. located?
- Pterygopalatine Fossa
What branch is given off by the inferior alveolar a.?
- Mylohyoid a. that runs with n. to mylohyoid in the mylohyoid groove
Between what two structures is the pterygoid plexus located?
Between:
- medial and lateral Pterygoid mm.
- Lateral Pterygoid and Temporalis mm.
What areas drain to the pterygoid Plexus?
- nasal cavity
- Oral Cavity
- Roof and lateral wall
- all teeth
- mm. of infratemporal fossa
- paranasal sinuses
- nasopharynx
What two major veins drain to the pterygoid plexus anterioly and posteriorly?
Anterior:
- Deep Facial v. (=> facial v.)
Posterior:
- Maxillary v. (=> Retromandibular v.)
What artery and nerve can often be found between the upper and lower head of the LATERAL pterygoid muscle?
- Buccal n. (V3)
- Maxillary a.
* ***NOTE: that the maxillary a. is variable
T or F: the medial pterygoid muscle arises from two different bones?
True, its origins are Lateral Pterygoid Plate (of sphenoid) and Maxilla
Which side of the medial pterygoid muscle can the following be found on?
- lingual a./n.
- Inferior Alveolar a./n.
All nerves are related vessels are found on the LATERAL surface of the muscle nearest the mandible
What structures does the lateral ligament of TMJ span?
From:
- Articular Tubercle
To:
- Neck of Mandible
T or F: the head of the mandible articulates directly with the mandibular fossa.
False, the articular disk separates the two structures dividing it into upper and lower portions
What vunerable junction is found in the floor of the Temporal fossa?
- Bones involved?
Pterion
Formed by:
- Temporal Bone (squamous pt)
- Parietal
- Frontal
- Sphenoid (greater wing)
How do structures in the infratemporal fossa communicate with those in the temporal fossa?
- They move deep to the zygomatic arch
Deep to:
- Zygomatic and Temporal
Superficial to:
- Greater wing of Sphenoid and Squamous Temporal
T or F: the mandibular division of trigeminal is the only part with motor function
True
What embryonic structure is the temporalis derived from?
- 1st Pharyngeal Arch along with MAST-MATT
***Remember innervation to all of these muscles is BE
What two spaces are all of the muscles of mastication located in?
- Temporal Fossa
2. Infratemporal Fossa
Differentiate the function of the anterior fibers of temporalis from the posterior fibers?
- Posterior Fibers = Retraction
- Anterior Fibers = Elevation
When is the gliding motion of the of the jaw used?
- which part of TMJ is involved?
- Wide Opening of the mouth when Protrusion is needed
- Superior part of the joint is involved in gliding
What are the superior continuations of investing fascia?
- Medial
- Anterolateral
- Posterolateral
Medial:
- Pterygoid Fascia
Anterolateral:
- Massenteric fascia
Posterolateral:
- Parotid Fascia
**Note: both lateral fascia layers (massenteric and parotid) are cont. with each other
T or F: the pterygoid fascia is continuous with temporalis fascia
False, Temporalis fascia is continuous with massenteric fascia inferiorly
T or F: Temporalis fascia has both superficial and deep layers and serves as a point of attachment for the muscle
True
Which part of the maxillary a. contains mostly muscular branches?
- Pterygoid Component, running along lateral Pterygoid
Which part(s) of the maxillary a. is/are in the pterygopalatine fossa?
- Third Part only
What do the 1st and 2nd branches off of maxillary supply?
- Deep Auricular - TMJ, EAM, Ext. Tymp. membrane
2. Tympanic - Int. Tymp. membrane
You pull a molar and it starts bleeding, what arteries are supplying the blood?
Inferior Alveolar => Maxillary a.
What arteries run deep to the temporalis muscle?
- Deep Temporal aa.
You bite your cheek and it bleeds, what artery is supplying the blood?
Buccal a. => maxillary
T or F: the Buccal a. runs with the buccal branch of VII
FALSE, it runs with Buccal n. (V3)
What is supplied by the Buccal a.?
- Buccal Fat Pad
- Buccinator
- Buccal oral mucosa
What relationship exists between the middle meningeal a. and the ariculotemporal n.?
- Auriculotemporal forms a loop around middle meningeal
What is the venous equivalent of the maxillary artery?
Pterygoid Plexus - branches that accompany branches of the maxillary artery drain here
What links the facial vein to the pterygoid plexus?
- Deep Facial Vein
What nerve has GSA fibers to part of the parotid capsule and side of the head?
Auriculotemporal n.
Describe the course of the Auriculotemporal n.
- 2 roots encircle middle meningeal a. and cont. in posterior direction
- Runs along the upper part of the parotid
- Turns up to run with superficial temporal a.
Describe the innervation of teeth in the mandible.
Molars and Premolars:
- Inferior Dental Plexus => inf. alveolar n.
Canine and Incisor Teeth:
- Incisive branches => inf. alveolar n.
What provides SA innervation to the tongue and soft palate?
CN VII:
Tongue (anterior 2/3)
- Chorda Tympani
Soft Palate
- Greater Petrosal
Where are the cell bodies for taste fibers of cranial n. VII?
Geniculate Ganglion
What brings sympathetic fibers to the submandibular and sublingual glands?
Facial a.
Lingual a.
Where does the branchiomotor component of CN VII exit the skull?
Stylomastiod Foramen
T or F: pain from TMJ can be referred
True
