Infratemporal Fossa

Nervous Structures

Kristine Joy LeyvaDMD1-A

I. Mandibular Nerve

- largest of the 3 divisions of CN V

- Mixed nerve- large sensory and small

motor root that unite after passing through foramen ovale to enter infratemporal fossa

Anterior Division: Masseteric

laterally superior to lateral pterygoid M.

anterior to TMJ and posterior of temporalis

mandibular notch

small branch to TMJ

Anterior Division: Anterior and Posterior Deep Temporal

superior to lateral pterygoid M.; between skull and temporalis; pass deep to muscle it innervates

Anterior Division: Medial Pterygoid

enters deep surface of muscle

Anterior Division: Buccal

anterior between 2 heads of lateral pterygoid

descends along lower part of temporalis

supply skin of buccinator

mucous membrane

gingiva along mandibular molars

Posterior Division: Auriculotemporal

arise from 2 roots

runs posteriorly, inferior to lateral pterygoid

medial aspect of neck of mandible

superiorly between auricle and condyle of mandible deep to parotid gland

ascends over zygomatic arch

divides to superficial temporal branches

Posterior Division: Lingual

inferior to lateral pterygoid and medial and anterior to I.A.N.

joins Chorda Tympani

between medial pterygoid and ramus of mandible

oral cavity

Posterior Division: Inferior Alveolar

descends with inferior alveolar artery

inferior to lateral pterygoid

between sphenomandibular ligament and ramus of mandible

mandibular foramen

INNERVATES: lower teeth and gingiva from premolars anteriorly to midline

Posterior Division: Mylohyoid

branch form I.A.N

descends in a groove on deep side of ramus

superficial surface of Mylohyoid M.

II. Maxillary Nerve: Posterior Superior Alveolar Nerve

pterygomaxillary fissure

infratemporal fossa (on posterior surface of maxilla along maxillary tuberosity)

gingival branch

enter posterior surface of maxilla

innervate maxillary sinus and molars

III. Chorda Tympani

SOURCE: branch from facial n. in tympanic cavity

preganglionic sympathertic fibers to submandibular ganglion and taste fibers to anterior 2/3 of tongue

enter tympanic cavity and lies along tympanic membrane and malleus

petrotympanic fissurejoins lingual nerve in infratemporal fossa

IV. Lesser Petrosal

SOURCE: tympanic plexus along promontory of the ear and re-forms as lesser petrosal nerve

middle ear cavity

preganglionic parasympathetic and postganglionic parasympathetic to parotid gland

groove for lesser petrosal n.

foramen ovale

infratemporal fossa joins otic

ganglion

V. Otic Ganglion

Postganglionic parasympathtic fibers

auriculotemporal branch (CN V)

parotid gland

CHARACTERISTICS OF CELL BODY: a collection of nerve cell bodies; located in infratemporal fossa; small stellate-shaped ganglion; located inferior to foramen ovale, medial V₃

Parasympathetics of Parotid Gland

I. Preganglionic Neuron

Preganglionic parasympathetic fibers

Inferior salivatory nucleus in medulla

glossopharyngeal N.

jugular foramen

Glossopharyngeal n.

tympanic branch of IX

tympanic plexus

lesser petrosal nerve

otic ganglion

NAME OF CELL BODY: inferior salivatory nucleusCHAR. OF CELL BODY: a collection of nerve cell bodies located in the medulla

II. Postganglionic Neuron

postganglionic parasympathetic fibers

otic ganglion

auriculotemporal branch (CN V)

parotid gland

NAME OF CELL BODY: otic ganglionCHAR. OF CELL BODY: a collection of nerve cell bodies; small stellate-shaped ganglion; located inferior to foramen ovale, medial V₃