Infratemporal Fossa

Gross Anatomy

Temporal and Masseteric Regions; Infratemporal Fossa


Anatomy Tables for Today's Topic


Bones and Cartilages of the Neck
Muscles
Nerves
Arteries
Veins
Joints and Fascia
Topographic Anatomy

Bones

Bone/Cartilage Structure Description Notes
mandible the U-shaped bone forming the lower jaw contains the inferior teeth; formed from the mesenchyme of the 1st pharyngeal arch, and its muscles are innervated by the nerve of the 1st arch (mandibular division of cranial nerve V)
body the anterior part of the mandible paired halves are fused in the midline at the symphysis menti
symphysis menti the midline symphysis between the two halves of the mandible the two halves of the mandible fuse during the first postnatal year
mental protuberance the projection on the anterior midline of the mandible the bone of the chin; mental means relating to the mind, a reference to the act of resting the chin on the hand while thinking (see the sculpture by Rodin: "The Thinker")
mental spines (genial tubercles) the spines on the inner surface of the mandible posterior to the mental protuberance attachment site for the genioglossus and geniohyoid mm.
mylohyoid line the ridge running obliquely from posterosuperior to anteroinferior on the medial surface of the body of the mandible attachment site for the mylohyoid muscle; the submandibular gland is located inferior to this line and the sublingual gland is located superior to this line
mental foramen the opening on the anterior surface of the body of the mandible inferior to the premolar teeth transmits the mental neurovascular bundle; covered superficially by the depressor anguli oris and depressor labii inferioris mm.
ramus the angled portion of the mandible that joins the posterior portion of the body it rises nearly vertically from the body; the chondyloid process and the coronoid process extend from the superior end of the ramus; the mandibular foramen is located on the medial surface of the ramus; the medial pterygoid m. attaches to the medial surface and the masseter m. attaches to the lateral surface of the ramus
angle the posteroinferior bend formed by the union of the body and the ramus
mandibular foramen the opening on the medial surface of the ramus it is the opening into the mandibular canal; it transmits the inferior alveolar neurovascular bundle
mandibular canal the canal that runs through the body of the mandible it transmits the inferior alveolar neurovascular bundle from the infratemporal fossa to the mandibular teeth and gingivae
lingula the projection of bone medial to the mandibular foramen it is the attachment site of the inferior end of the sphenomandibular ligament
coronoid process the process that projects anterosuperiorly from the ramus of the mandible it is the attachment site of the temporalis m.
condylar process the rounded process that projects posterosuperiorly from the ramus of the mandible it articulates with the mandibular fossa of the temporal bone
mandibular notch the notch between the coronoid and condylar processes it transmits the masseteric neurovascular bundle from the infratemporal fossa to the deep surface of the masseter m.
mandibular neck the constriction below the articular chondyle on the chondylar process of the mandible part of the lateral pterygoid m. inserts into the pterygoid fossa of the mandibular neck
pterygoid fossa of the neck a shallow depression on the anterior surface of the neck of the mandible part of the lateral pterygoid m. inserts into the pterygoid fossa of the mandibular neck
parietal a broad, flat bone forming the lateral surface of the skull paired; this bone articulates with the contralateral parietal bone in the midline at the sagittal suture; it articulates anteriorly with frontal bone at coronal suture; it articulates posteriorly with the occipital bone at the lambdoid suture; it articulates inferiorly with the greater wing of the sphenoid bone at the pterion, the squamous part of the temporal bone at the squamous suture and the mastoid part of the temporal bone at the parietomastoid suture
inferior temporal line an arching ridge on the external surface of the parietal bone it is an attachment site for the temporalis muscle
superior temporal line an arching ridge on the external surface of the parietal bone it is an attachment site for the temporalis muscle and the temporal fascia
parietal foramen an opening in the parietal bone located near the sagittal suture it transmits the parietal emissary vein, a valveless vein which connects the scalp to the cranial cavity
granular foveolae small pits located on the inner table of the parietal bone for the arachnoid granulations
temporal bone forming the lateral side of the skull temporal refers the passage of time, which is marked by the appearance of gray hair on the side of the head
squamous part the thin flat portion of the temporal bone that constitutes the side of the skull above the ear it articulates with the parietal bone and the greater wing of the sphenoid bone at the squamous suture
zygomatic process the projection of bone that arises anterior to the external acoustic meatus it articulates with the temporal process of the zygomatic bone to form the zygomatic arch
mandibular fossa the depression located medial to the origin of the zygomatic process it articulates with the condylar process of the mandible
articular tubercle an inferior projection located anterior to the mandibular fossa dislocations of the temporomandibular joint result when the mandibular condyle slides anterior to this structure
styloid process the spike of bone that projects inferiorly from the petrous part of the temporal bone it is the attachment site for the stylohyoid, styloglossus and stylopharyngeus mm. and the stylomandibular and stylohyoid ligaments
external acoustic meatus the opening in the lateral surface of the temporal bone it extends medially from the surface to the tympanic membrane; it allows sound to reach the tympanic membrane; the medial 1/3 of the external acoustic meatus is bony and the lateral 2/3 is formed by cartilage
sphenoid an irregularly shaped bone forming the central portion of the skull it has many parts, including a body, greater wing, lesser wing and pterygoid plates
greater wing of the sphenoid broad plate of bone swinging laterally from the body of the sphenoid bone bilateral; it forms the medial part of the floor of the middle cranial fossa, part of temporal fossae laterally, and the posterior part of the lateral wall of orbit; it articulates anteriorly with the zygomatic bone, superiorly with the frontal & parietal bones (at the pterion), posteriorly with the squamous & petrous portions of the temporal bone
foramen rotundum opening in the floor of the middle cranial fossa through the greater wing of the sphenoid bone it transmits the maxillary division of the trigeminal nerve
foramen ovale opening in the floor of the middle cranial fossa through the greater wing of the sphenoid bone it transmits the mandibular division of the trigeminal nerve; it is located between the foramen rotundum and the foramen spinosum
foramen spinosum opening in the floor of the middle cranial fossa through the greater wing of the sphenoid bone it transmits the middle meningeal artery and the meningeal br. of the mandibular division of the trigeminal nerve (cranial nerve V)
spine of the sphenoid process of bone that projects inferiorly from undersurface of greater wing of the sphenoid it is the superior attachment for the sphenomandibular ligament
pterygoid process process that projects inferiorly from the junction of the body & greater wing of the sphenoid bone it has several parts: lateral & medial pterygoid plates, hamulus, pterygoid fossa, scaphoid fossa; the pterygoid plates are separated by the large pterygoid fossa throughout most of their length, and by the small scaphoid fossa superiorly
lateral pterygoid plate thin plate of bone that projects posterolaterally from the pterygoid process it is the attachment site of the lateral & medial pterygoid muscles (lateral pterygoid m. on its lateral surface, medial pterygoid m. on its medial surface)
medial pterygoid plate thin plate of bone that projects posteriorly from the pterygoid process it is the attachment of the superior pharyngeal constrictor m. & the pharygobasilar fascia
pterygoid hamulus hook-like projection from the inferior end of the medial pterygoid plate it acts as a pulley for the tendon of the tensor veli palatini m.
pterygoid canal canal that occurs at the junction of the greater wing, the pterygoid process and the body of the sphenoid bone it transmits the nerve of the pterygoid canal from the pterygoid region to the pterygopalatine fossa
maxilla bone forming the midface it forms the inferior orbital margin and contains the teeth and maxillary sinus
maxillary tuberosity the roughened posterior aspect of the body of the maxilla the posterior superior alveolar nn. Enter the maxilla directly superior to this structure

Muscles

Muscle Origin Insertion Action Innervation Artery Notes
masseter zygomatic arch and zygomatic bone lateral surface of the ramus and angle of the mandible elevates the mandible nerve to the masseter, from the mandibular division of the trigeminal nerve (V) masseteric branch of the maxillary a. a powerful chewing muscle
temporalis temporal fossa and the temporal fascia coronoid process of the mandible and the anterior surface of the ramus of the mandible elevates the mandible; retracts the mandible (posterior fibers) anterior and posterior deep temporal nerves from the mandibular division of the trigeminal nerve (V) anterior and posterior deep temporal aa. a powerful chewing muscle; a derivative of the first pharyngeal arch
lateral pterygoid superior head: greater wing of the sphenoid bone; inferior head: lateral surface of the lateral pterygoid plate superior head: capsule and & articular disk of the temporomandibular joint; inferior head: neck of the mandible protracts the mandible; opens the mouth; active in grinding actions of chewing lateral pterygoid branch of the mandibular division of the trigeminal nerve (V) pterygoid branch of the maxillary a. the only one of the muscles of mastication that opens the mouth; the superior head of lateral pterygoid is sometimes called sphenomeniscus due to its insertion into the disc of the temporomandibular joint
medial pterygoid medial surface of the lateral pterygoid plate, pyramidal process of the palatine bone, tuberosity of the maxilla medial surface of the ramus and angle of the mandible elevates and protracts the mandible medial pterygoid branch of the mandibular division of the trigeminal nerve (V) pterygoid branch of the maxillary a. this muscle mirrors the masseter m. in position and action with the ramus of the mandible between the two mm.

Nerves

Nerve Source Branches Motor Sensory Notes
mandibular division of the trigeminal n. trigeminal ganglion; motor root arises from the pons meningeal br., medial pterygoid and lateral pterygoid nn., masseteric n., anterior and posterior deep temporal nn., buccal n., auriculotemporal n., lingual n., inferior alveolar n. SVE: mylohyoid m., anterior belly of the digastric m.; tensor tympani m., tensor veli palatini m.; muscles of mastication (temporalis, masseter, medial pterygoid and lateral pterygoid) GSA: skin of the lower lip and jaw extending superiorly above level of the ear; mucous membrane of the tongue and floor of the mouth; lower teeth and gingiva of the mandibular alveolar arch also known as: V3; passes through the foramen ovale to exit the middle cranial fossa; the otic ganglion is associated with the medial side of V3 below the foramen ovale; the auriculotemporal n. carries postganglionic parasympathetic axons to the parotid gland; the submandibular ganglion is associated withe the lingual n. near the submandibular gland; postganglionic parasympathetics from the submandibular ganglion supply the submandibular gland and the sublingual gland
auriculotemporal n. mandibular division of the trigeminal n. (V3) parotid brs., articular brs., anterior auricular brs. secretomotor to the parotid gland by carrying postganglionic parasympathetic fibers from the otic ganglion; [preganglionic parasympathetic fibers originate in the lesser petrosal br. of the glossopharyngeal n. (IX)] skin of anterior ear and the skin anterosuperior to the ear; part of the external auditory meatus; temporomandibular joint two roots of the auriculotemporal n. encircle the middle meningeal a.
inferior alveolar n. mandibular division of the trigeminal n.(V3) n. to mylohyoid; inferior dental plexus; mental nerve mylohyoid muscle and anterior belly of the digastric m. via n. to mylohyoid teeth of the mandible; skin of the chin inferior alveolar n. passes through the mandibular canal; the mental n. is its terminal branch which emerges through the mental foramen
lingual n. mandibular division of the trigeminal n. (V3) no named branches none general sense from the anterior 2/3 of the tongue and floor of the mouth lingual n. is joined by the chorda tympani (taste and preganglionic parasympathetic) from the facial n. in the infratemporal fossa; the submandibular ganglion hangs from the lingual nerve in the paralingual space
buccal branch of the trigeminal n. mandibular division of the trigeminal n. (V3) no named branches no motor branches skin of the cheek, mucosa lining the cheek not a motor nerve; easily confused with the buccal branch of the facial n.
facial n. pons and medulla: nucleus solitarius of medulla via nervus intermedius (SVA sensory root) from geniculate ganglion; superior salivatory nucleus (GVE preganglionic parasympathetic) of pons via nervus intermedius; facial motor nucleus of pons via motor root greater petrosal n. (preganglionic parasympathetic to pterygopalatine ganglion, postganglionic parasympathetic travels with brs. of maxillary division of V), chorda tympani (SVA taste from anterior 2/3 of the tongue; preganglionic parasympathetic to the submandibular ganglion, postganglionic parasympathetic to the submandibular and sublingual glands), n. to stapedius, posterior auricular n., intraparotid plexus with temporal, zygomatic, buccal, marginal mandibular & cervical brs. stapedius m., stylohyoid m., posterior belly of digastric m., muscles of facial expression; secretomotor to lacrimal, submandibular, sublingual, and mucous glands of the nasal and oral cavities taste (SVA) from the anterior 2/3 of the tongue; part of the skin of the external auditory meatus also known as: CN VII, 7th cranial nerve; exits the posterior cranial fossa by passing into the internal acoustic meatus, goes through the facial canal; motor to muscles of facial expression exits the skull at the stylomastoid foramen
chorda tympani facial (VII) no named branches secretomotor to the submandibular and sublingual glands (it carries preganglionic parasympathetic axons to the submandibular ganglion) taste to the anterior 2/3 of the tongue chorda tympani joins the lingual nerve in the infratemporal fossa and continues with it to the tongue
buccal branches of the facial n. facial n. (VII) no sensory branches zygomaticus major & minor, buccinator, orbicularis oris, levator anguli oris, levator labii superioris & alaque nasi, risorius, procerus, nasalis no sensory branches not a sensory nerve; easily confused with the buccal branch of the trigeminal n.
digastric m., posterior belly, n. to facial n. (VII) no named branches posterior belly of the digastric m. none the anterior belly of the digastric m. is formed by mesenchyme from the 1st pharyngeal arch and is supplied by the n. to the mylohyoid m. (V3)
otic ganglion preganglionic parasympathetic via the lesser petrosal, from the tympanic n. of the glossopharyngeal n. (IX) postganglionic parasympathetic axons distribute with the parotid brs. of the auriculotemporal n. (from V3) secretomotor to the parotid gland none a parasympathetic ganglion; the otic ganglion hangs off of the mandibular division of the trigeminal n. (V3) inferomedial to the foramen ovale
masseteric n. mandibular division of the trigeminal n. no named branches masseter m. none masseteric n. passes over the mandibular notch to reach the deep surface of the masseter m.
mental n. inferior alveolar n. no named branches none skin of the chin the lower lip mental n. passes through the mental foramen
mylohyoid, n. to inferior alveolar n., a branch of the mandibular division of the trigeminal n. (V3) no named branches mylohyoid m., anterior belly of the digastric m. none n. to mylohyoid arises near the lingula of the mandible; course within the mylohyoid groove of the mandible
temporal, anterior deep mandibular division of the trigeminal n. (V3) no named branches temporalis m. no cutaneous branches a branch of the motor root of CN V; temporalis m. developed from the mesenchyme of the first pharyngeal arch
temporal, posterior deep mandibular division of the trigeminal n. (V3) no named branches temporalis m. no cutaneous branches a branch of the motor root of CN V; temporalis m. developed from the mesenchyme of the first pharyngeal arch
trigeminal n. motor root arises from the trigeminal motor nucleus in the pons (SVE); sensory part arises from the trigeminal ganglion (GSA) and projects into the pons to the primary sensory nucleus of V or more inferiorly to the nucleus of the spinal root of V (medulla and upper spinal cord) ophthalmic, maxillary and mandibular divisions SVE: anterior belly of the digastric m., mylohyoid m., tensor veli palatini m., tensor tympani m.; muscles of mastication: temporalis m., masseter m., lateral pterygoid m., medial pterygoid m. skin of the face; mucous membranes of the nasal and oral cavities; general sensation (GSA) to the anterior 2/3 of the tongue also known as: CN V, 5th cranial nerve; some brs. carry pre- or postganglionic parasympathetic fibers; the trigeminal n. divides into three divisions at the trigeminal ganglion; SVE supplies muscles of 1st pharyngeal arch origin

Arteries

Artery Source Branches Supply to Notes
maxillary external carotid a. deep auricular a., anterior tympanic a., middle meningeal a., inferior alveolar a., masseteric a., posterior deep temporal a., anterior deep temporal a., buccal a., posterior superior alveolar a., infraorbital a., a. of the pterygoid canal, descending palatine a., sphenopalatine a. deep face, infratemporal fossa, tympanic cavity, muscles of mastication maxillary a. may course medial or lateral to the lateral pterygoid m.
inferior alveolar maxillary a. lingual br., mylohyoid a., dental brs., mental a. mandibular teeth and gingiva; mandible; mylohyoid m. inferior alveolar a. runs with the inferior alveolar nerve within the mandibular canal
meningeal, middle maxillary a. frontal br., parietal br., petrous br., superior tympanic br. most of the dura mater (approx. 80%), bones of the cranial vault middle meningeal a. passes through the foramen spinosum; it may be torn by a fracture at the pterion; it is encircled by the auriculotemporal n.
temporal, anterior deep maxillary a. no named branches anterior part of temporalis m. and surrounding deep tissues anterior deep temporal a. branches in the infratemporal fossa and runs deep to temporalis m.
temporal, middle superficial temporal a. no named branches temporalis m. middle temporal a. anastomoses with the posterior br. of the deep temporal a.
temporal, posterior deep maxillary a. no named branches posterior part of the temporalis m. posterior deep temporal a. branches in the infratemporal fossa and runs deep to temporalis m.
temporal, superficial external carotid a. transverse facial a.; anterior auricular brs.; zygomatico-orbital a.; middle temporal a.; frontal br.; parietal br. scalp of the lateral side of the head; lateral face; temporalis m. superficial temporal a. and maxillary a. are the terminal branches of the external carotid a.
buccal maxillary a. no named branches cheek and associated muscles buccal a. runs with the buccal branch of CN V
masseteric maxillary a. no named branches masseter m. masseteric a. passes through the mandibular notch to enter the deep surface of the masseter m.
sphenopalatine maxillary a. posterior lateral nasal brs., posterior septal brs. posterolateral nasal wall, posteroinferior nasal septum, hard palate behind the maxillary incisor teeth sphenopalatine a. accompanies the nasopalatine n.
infraorbital maxillary a. anterior superior alveolar a., middle superior alveolar a. maxillary sinus, maxillary incisors, canine and premolar teeth, skin of the cheek below the orbit, mucosa over the maxillary alveolar arch and the adjacent cheek infraorbital a. is one of four terminal branches of the maxillary a. (see also: descending palatine a., sphenopalatine a., posterior superior alveolar a.)
posterior superior alveolar maxillary a. dental brs., mucosal brs. maxillary molar teeth; part of the maxillary sinus posterior superior alveolar a. enters the maxilla in the infratemporal fossa
descending palatine maxillary a. greater palatine a., lesser palatine a. palate descending palatine a. accompanies the greater palatine n. within the palatine canal
palatine, greater descending palatine a. no named branches hard palate, palatine glands, palatine mucosa greater palatine a. accompanies the greater palatine n., it is endangered by anesthetic injections for dental procedures
palatine, lesser descending palatine a. no named branches muscles of the soft palate, mucosa and glands of the soft palate, upper part of the tonsil bed lesser palatine a. is endangered by anesthetic injections for dental procedures
auricular, deep maxillary a. no named branches external auditory meatus, tympanic membrane deep auricular a. is small and difficult to dissect
carotid, external common carotid a. superior thyroid a., ascending pharyngeal a., lingual a., facial a., occipital a., posterior auricular a., maxillary a., superficial temporal a. upper neck, face and scalp external carotid a. is the primary blood supply to the face and superficial head; the maxillary a. and superficial temporal a. are its terminal branches
mylohyoid inferior alveolar a. no named branches mylohyoid m. mylohyoid a. accompanies the mylohyoid n. to the mylohyoid m.; a rare artery because it enters the superficial surface of its target muscle

Veins

Vein Tributaries Drains Into Regions Drained Notes
plexus, pterygoid venous descending palatine v., sphenopalatine v., infraorbital v., posterior superior alveolar v., anterior deep temporal v., posterior deep temporal v., middle meningeal v., masseteric v., inferior alveolar v. maxillary v. meninges, nasal cavity, infratemporal fossa valveless; the pterygoid plexus is connected with the cavernous sinus and the pharyngeal venous plexus
retromandibular v. formed by the union of the superficial temporal v. and maxillary v. anterior and posterior divisions of the retromandibular v. side of the head and scalp; deep face retromandibular v. is contained within the parotid gland; anterior division unites with the facial v. to form the common facial v.; posterior division unites with the posterior auricular v. to form the external jugular v.

Joints and Fascia

Joint or ligament Description Notes
sphenomandibular ligament the ligament that attaches to the spine of the sphenoid bone superiorly and the lingula of the mandible inferiorly paired; it is a specialization of the pterygoid fascia and is a remnant of the mesenchymal core of the first pharyngeal arch (Meckel's cartilage)
stylohyoid ligament the ligament that connects the styloid process with the lesser horn of the hyoid bone a syndesmosis; paired; a remnant of the mesenchymal core of the second pharyngeal arch (Reichert's cartilage)
stylomandibular ligament the ligament that connects the styloid process with the angle of the mandible paired; a thickening of the parotid fascia
temporomandibular joint the articulation between the head of the condylar process of the mandible and the mandibular fossa of the temporal bone a synovial hinge joint; it is separated into two joint spaces by an intracapsular fibrous articular disc; gliding action occurs superior to the articular disc and hinge action occurs inferior to the disc

Topographical Anatomy

Structure/Space Description/Boundaries Significance
infratemporal fossa area medial to the angle of the mandible bounded above by the infratemporal surface of the greater wing of the sphenoid bone, anteriorly by the alveolar border of the maxilla, laterally by the ramus of the mandible and deeply by the lateral pterygoid plate of the sphenoid bone infratemporal fossa has the foramen rotundum and foramen spinosum in its roof; maxillary a. and its branches are located here; branches of the mandibular division of the trigeminal nerve (V3) are located here


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Some of the material presented in these tables is contained in the book:
MedCharts Anatomy by Thomas R. Gest and Jaye Schlesinger
Published by ILOC, Inc., New York. Copyright 1995.

Content of these tables has been edited for use in this course by Patrick W. Tank, Ph.D.
Copyright 2007, Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences.

Unauthorized use is prohibited.