Anatomy Tables - Infratemporal Fossa & Oral Cavity

Osteology

BoneStructureDescription
temporaltemporal lines (TG7-04)two low ridges that run parallel to each other, arching across the lateral surface of the calvaria; they define the upper limit of the temporalis m. origin
articular tubercle (TG7-06)inferior projection anterior to mandibular fossa; important in dislocations of the mandible
mandibular fossa (N4, TG7-32) articulates with condylar process of mandible
sphenoid body (N8, TG7-07, TG7-08) central part, containing sinuses (Greek, sphenoid = wedge-shaped)
infratemporal fossa (N4, TG7-32) bounded superiorly by the infratemporal surface of greater wing of the sphenoid and inferiorly by the alveolar border of the maxilla; bounded laterally by the ramus of the mandible and medially by the lateral pterygoid plate of the sphenoid bone
foramen ovale (N4, N8, N11, TG7-06, TG7-07, TG7-32) through greater wing between foramen rotundum & foramen spinosum; transmits mandibular division of trigeminal nerve
foramen spinosum (N8,N11, TG7-06, TG7-07) through greater wing; transmits middle meningeal artery
lateral pterygoid plate (N6, N8, TG7-06, TG7-08) projects posterolaterally from pterygoid process; attachment of lateral & medial pterygoid muscles (Greek, pterygoid = wing-shaped)
medial pterygoid plate (N6, N8, TG7-06, TG7-08) projects posteriorly from pterygoid process; attachment of superior pharyngeal constrictor & pharyngobasilar fascia (Greek, pterygoid = wing-shaped)
mandible body (N15, TG7-32B, TG7-32C) U-shaped, halves fused at symphysis menti
coronoid process (N15, TG7-32B) anterosuperior projection from ramus; attachment of temporalis muscle
condyle (N15, TG7-32B) posterosuperior projection from ramus; articulates with mandibular fossa of temporal bone; constricted below articular surface at neck of mandible (Greek, kondylos = knuckle)
mandibular notch (N15, TG7-32B) notch between the coronoid and condylar processes; transmits masseteric neurovascular bundle
lingula (N15, TG7-32C) projection of bone medial to mandibular foramen; attachment of sphenomandibular ligament (Latin, lingula = tongue)
mandibular foramen (N15, TG7-32C) on medial surface of ramus, opening to mandibular canal; transmits inferior alveolar neurovascular bundle
pterygoid fovea (N15, TG7-32C) depression on anterior side of neck of mandible; insertion of lateral pterygoid m. (Greek, pterygoid = wing-shaped)

Muscles

MuscleOriginInsertionActionInnervationNotesImage
masseter (N54, TG7-31) zygomatic arch and zygomatic bonelateral surface of ramus and angle of mandibleelevates mandiblenerve to masseter, from mandibular division of trigeminal nerve (V)a powerful chewing muscle (Greek, masseter = the chewer)
temporalis (N54, TG7-31, TG7-34) temporal fossa and temporal fasciacoronoid process and anterior surface of the ramus of the mandibleelevates mandible; retracts mandible (posterior fibers)anterior and posterior deep temporal nerves from mandibular division of trigeminal nerve (V)a powerful chewing muscle
pterygoid, lateral (N55, TG7-34) superior head: greater wing of sphenoid; inferior head: lateral surface of lateral pterygoid platesuperior head: capsule & articular disk of temporomandibular joint; inferior head: neck of mandibleprotracts mandible; opens mouthlateral pterygoid branch of mandibular division of trigeminal nerve (V)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 (Greek, pterygoid = wing-shaped)
pterygoid, medial (N55, TG7-34) medial surface of the lateral pterygoid plate, pyramidal process of palatine bone, tuberosity of maxillamedial surface of ramus and angle of mandibleelevates and protracts mandiblemedial pterygoid branch of mandibular division of trigeminal nerve (V)this muscle mirrors the masseter m. in position and action with the ramus of the mandible between (Greek, pterygoid = wing-shaped)
digastric (N27, N28 TG7-12, TG7-17) anterior belly: digastric fossa of the mandible; posterior belly: mastoid notch of the temporal bone body of the hyoid via a fibrous loop over an intermediate tendon elevates the hyoid bone; depresses the mandible anterior belly: mylohyoid nerve, from the mandibular division of the trigeminal nerve (V); posterior belly: facial nerve (VII) the digastric m. forms two sides of the submandibular triangle; it is formed from mesenchyme derived from the first two pharyngeal arches, hence its dual innervation
geniohyoid (N53, N59,N63, TG7-38, TG7-40) mental spines of mandiblebody of hyoid boneelevates hyoid; depresses mandibleC1 ventral primary ramus via fibers carried by hypoglossal nervethyrohyoid and geniohyoid receive ansa cervicalis fibers that travel with the hypoglossal nerve distal to the superior limb of the ansa cervicalis
genioglossus (N63, N59, TG7-38, TG7-40) mental spine on inner aspect of mental symphysisfans out to insert into the tongue from tip to baseprotrudes tongue (inferior fibers); depresses tongue (middle fibers)hypoglossal nerve (XII)an extrinsic muscle of the tongue; XII innervates all tongue muscles except palatoglossus (innervated by vagus (X), as are most of the palate and pharynx muscles)
hyoglossus (N53, N59, TG7-40) upper border of greater horn of the hyoid and body of the hyoid bonemingles with intrinsic muscles of the tonguedepresses sides of tongue; retracts tonguehypoglossal nerve (XII)an extrinsic muscle of the tongue
mylohyoid (N27,N28, N53, N59, TG7-12, TG7-37, TG7-40) mylohyoid line of mandible midline raphe and body of the hyoid bone elevates the hyoid bone and the tongue; depresses the mandible mylohyoid nerve from the inferior alveolar nerve, a branch of the mandibular division of the trigeminal nerve (V) the nerve to mylohyoid also innervates the anterior belly of digastric m.; both muscles are derivatives of the second pharyngeal arch
styloglossus (N59, N68, TG7-20, TG7-40) styloid processside of the tongueretracts and elevates tonguehypoglossal nerve (XII)an extrinsic muscle of the tongue
stylohyoid (N59, TG7-17, TG7-40) posterior side of the styloid process splits around the intermediate tendon of the digastric m. to insert on the body of the hyoid bone elevates and retracts the hyoid bone facial nerve (VII) facial nerve innervates both the stylohyoid m. and the posterior belly of the digastric m. shortly after exiting from the stylomastoid foramen

Nerves

NerveSourceBranchesMotorSensoryNotes
mandibular (N46, N55, TG7-37, TG7-84A, TG7-84B, TG7-84C, TG7-85A, TG7-85B) trigeminal ganglion; motor root of trigeminal from ponsmeningeal br., medial & lateral pterygoid, masseteric, anterior & posterior deep temporal, buccal, auriculotemporal, lingual, inferior alveolarmylohyoid, anterior belly of digastric; tensor tympani, tensor veli palatini; muscles of mastication (temporalis, masseter, medial & lateral pterygoid)GSA: skin of lower lip & jaw extending superiorly above level of ear; GVA: tongue, & floor of mouth, lower teeth & gingivaalso known as: V3, mandibular division of trigeminal; passes through foramen ovale; otic ganglion hangs off medial side of V3 below foramen ovale; auriculotemporal n. carries postganglionic parasympathetic to parotid gland; submandibular ganglion hangs off lingual n. near submandibular gland; postganglionic parasympathetics reach this gland & sublingual gland
auriculotemporal (N46, N61,N122, TG7-30, TG7-84) mandibular division of trigeminal n. (V3)parotid brs., articular brs., anterior auricular brs.secretomotor to parotid gland: postganglionic parasympathetic from communicating br. of otic ganglion; preganglionic parasympathetic from lesser petrosal br. of glossopharyngeal n. (IX)skin of anterior ear & anterosuperior to ear; part of external auditory meatus; temporomandibular jointtwo roots of auriculotemporal encircle the middle meningeal a.
inferior alveolar (N42,N122, TG7-36, TG7-84) mandibular division of trigeminal (V3)n. to mylohyoid; inferior dental plexus; terminates as mental nervemylohyoid muscle via n. to mylohyoid teeth of mandible; skin of chin
mylohyoid, n. to (N42,N122, TG7-36, TG7-84)inferior alveolarmylohyoid, anterior belly of digastricarises near lingula of mandible
lingual (N55, N57, N65, TG7-37, TG7-84A, TG7-84C) mandibular division of trigeminal (V3)general sense from anterior 2/3rds of tongue, floor of mouthjoined by chorda tympani (taste & pregang. parasymp.) from facial n. in infratemporal fossa; submandibular gang. hangs from lingual nerve in paralingual space
buccal (N50, N128, TG7-37, TG7-84) mandibular division of trigeminal n. (V3)skin of cheek, oral mucosanot a motor nerve
chorda tympani (N46, N94,N123, TG7-37, TG7-84, TG7-88B) facial (VII)secretomotor to submandibular & sublingual glands (preganglionic parasympathetic to submandibular ganglion)taste to anterior 2/3rds of tonguejoins lingual nerve in infratemporal fossa and continues with it to the tongue (Latin, corda = cord; Greek, tympanum = a kettle drum)
masseteric (TG7-85A)mandibular division of trigeminalmasseterpasses over mandibular notch
temporal, anterior deep (N42, N122, TG7-36, TG7-85) mandibular division of trigeminal (V3) temporalis
temporal, posterior deep (N42, N122, TG7-36, TG7-85) mandibular division of trigeminal (V3) temporalis
trigeminal (TG7-81AB, TG7-81C, TG7-81D)pons: trigeminal motor nucleus (SVE) to motor root; spinal trigeminal nucleus from trigeminal ganglion (GSA) via sensory rootophthalmic, maxillary & mandibular divisionsSVE: temporalis, masseter, lateral & medial pterygoid, anterior belly of digastric, mylohyoid, tensor veli palatini, tensor tympaniskin of face, nasal & oral cavities, ant. 2/3rds of tongue (GSA only)also known as: CN V, 5th cranial nerve; some brs. carry pre- or postganglionic parasympathetic fibers; divides into three divisions at trigeminal ganglion; SVE supplies muscles of branchial arch origin
hypoglossal (N32, N71, N128, TG7-17, TG7-18, TG7-94AB, TG7-94C) medulla: hypoglossal nucleusbranches of C1 carried by this nerve are not considered to be branches of the hypoglossal nerveintrinsic and extrinsic muscles of the tongue (except palatoglossus m.)also known as: CN XII, 12th cranial nerve; passes through the hypoglossal canal; superior root of ansa cervicalis travels with the hypoglossal n.
ganglion, submandibular (N46, N59, N61, N122, TG7-37, TG7-40, TG7-84) preganglionic parasympathetic from chorda tympani accompanying lingual n.postganganglionic parasympathetic to submandibular & sublingual glandssecretomotor to submandibular & sublingual glandshangs off lingual n. above deep part of submandibular gland

Arteries

ArterySourceBranchesSupplyNotes
carotid, external (N69, TG7-19, TG7-34, TG7-35) common carotidsuperior thyroid, ascending pharyngeal, lingual, facial, occipital, post. auricular, maxillary & superficial temporal (terminal brs.)upper neck, face & scalpprimary blood supply to face & superficial head
maxillary (N69, TG7-19, TG7-34, TG7-35) external carotiddeep auricular, anterior tympanic, middle meningeal, inferior alveolar, masseteric, post. & ant. deep temporal, buccal, post. superior alveolar, infraorbital, art. of pterygoid canal, descending palatine, sphenopalatinedeep face, infratemporal fossa, tympanic cavity, muscles of masticationmay course medial or lateral to the lateral pterygoid m. in equal frequency
alveolar, inferior (N69, TG7-34, TG7-35) maxillary arterylingual branch, mylohyoid, dental, nutrient, mentallower teeth & gingiva, mandible, closely associated musclesruns with the inferior alveolar nerve within the mandibular canal
middle meningeal (N69, TG7-35) maxillaryfrontal br., parietal br., petrous br., superior tympanicmost of the dura mater (approx. 80%), cranial vault bonespasses through foramen spinosum; may be torn by fracture at pterion
temporal, anterior deep (N69, TG7-35) maxillarytemporalis anteriorlybranches in the infratemporal fossa and runs deep to temporalis m.
temporal, posterior deep (N69, TG7-35) maxillarytemporalis posteriorlybranches in the infratemporal fossa and runs deep to temporalis m.
buccal (N69, TG7-34, TG7-35) maxillarycheek and associated musclesruns with the buccal branch of CN V
masseteric (N69, TG7-34, TG7-35) maxillarymasseter m.
alveolar, posterior superior (N69, TG7-35) maxillary arterydental, mucosalupper molar teeth, part of maxillary sinusenters the maxilla in the infratemporal fossa
lingual (N69, N59, N51, TG7-19, TG7-40) external carotidsuprahyoid br., dorsal lingual brs., deep lingual, sublingualtongue, suprahyoid muscles, palatine tonsil

Veins

VeinTributariesDrains IntoRegion DrainedNotes
pterygoid plexus (N70, TG7-73) descending palatine, sphenopalatine, infraorbital, posterior superior alveolar, ant. & post. deep temporal, middle meningeal, masseteric, inferior alveolarmaxillary v.meninges, nasal cavity, infratemporal fossavalveless; connects with cavernous sinus & pharyngeal plexus (Latin, plexus = a braid)

Joints

JointDescriptionSignificance
temporomandibular joint (N12,N17, TG7-06 N16, TG7-32B, TG7-32C) synovial, hingeseparated into 2 joint spaces by intracapsular fibrous articular disc

Lymphatics

StructureLocationAfferents fromEfferents toRegions drained
tonsil, lingual (N58,N63, TG7-22, TG7-39) superior surface of root of tongue superior deep cervical nodes "guards" entrance of oropharynx part of tonsillar ring (of Waldeyer)

Viscera/Fascia

OrganLocation/Description
intrinsic muscles of the tongue (N126, TG7-38) includes the superior and inferior longitudinals, transverse, and vertical muscles
submandibular triangle (N60, N61, N69, N73, TG7-02, TG7-12, TG7-37) comprised of the submandibular gland and lymph nodes, hypoglossal nerve, mylohyoid nerve, and parts of the facial artery and vein
submandibular gland (N60, N61, N69, N73, TG7-12, TG7-37A, TG7-37B) salivary gland; located beneath mylohyoid in submandibular triangle; innervated by postgang. parasymp. fibers from submandibular gang.
sublingual gland (TG7-37A, TG7-37B) salivary gland; located beneath oral mucosa in floor of mouth; drains via multiple small ducts
submandibular duct (N60, N61, N69, N73, TG7-12, TG7-37A, TG7-37B) drains submandibular gland to sublingual caruncle in floor of mouth
foramen cecum (of tongue) (N58, TG7-39) located on midline of tongue in sulcus terminalis; remnant of thyroid diverticulum (Latin, foramen cecum = blind apeture)
vallate papillae (N58, TG7-39) located in line anteriorly along sulcus terminalis of tongue; possess taste buds in circular sulcus; a.k.a. circumvallate papillae
frenulum of tongue (N51, TG7-38) fold of mucous membrane under tongue (Latin, frenulum = a bridle, a narrow reflection or fold of mucous membrane, passing from a more fixed to a movable part)
sublingual caruncle (N51, TG7-38) papilla on lateral side of frenulum of tongue; opening of the duct of the submandibular gland

Clinical Terms

Term Definition
submandibular (Wharton's) duct calculus stone in the submandibular duct
TMJ syndrome/dislocation TMJ syndrome: Disorder of the temporo-mandibular joint(s) causing pain usually in front of the ear(s). TMJ Dislocation: Excessive contraction of the lateral pterygoids may cause the jaw to dislocate anteriorly (pass anterior to the anterior tubercles. This could happen during yawning or when taking a large bite. Also sideway blows to the chin when the mouth is open dislocates the TMJ on the side that receives the blow. TMJ dislocation is frequently accompanied by fracture of the mandible. Posterior dislocation of the TMJ is uncommon due to the resistence by the postglenoid tubercle and the strong intrinsic lateral or temporomandibular ligament. Care must be taken during repair in regards to the facial and the auriculotemporal nerve; injury to the auriculotemporal nerve leads to laxity and instability of the TMJ.
bruxism compulsive grinding or clenching of the teeth especially at night
LeForte fractures classically described fractures of the face which occur with trauma
  • LeForte I - a horizontal fracture through the maxillae just above the maxillary teeth
  • LeForte II - a fracture in which the maxillae are separated from the facial skeleton with the separated bone being pyramidal in shape and including the palate and maxillary teeth
  • LeForte III - a horizontal fracture in which the entire maxilla and one or more facial bones are separated from the upper face

The material presented in these tables is contained in the book:
MedCharts Anatomy by Thomas R. Gest & Jaye Schlesinger
Published by ILOC, Inc., New York
Copyright 1995, unauthorized use prohibited.
The excellent editorial assistance of
Dr. Pat Tank, UAMS
is gratefully acknowledged.