Download Maxillary nerve

Infratemporal
Fossa
Part II
Deep Contents of the
infratemporal fossa
Muscles: tensor palati and levator palati.
Nerve: Maxillary nerve and it branches.
Autonomic ganglion: Spheno-palatine
ganglion.
Arteries: 3rd part of maxillary artery and its
branches (mentioned before).
Tensor Palati
Origin: 1. Spine of sphenoid
2. Scaphoid fossa
3. Outer wall of auditory tube
Insertion: Palatine aponeurosis (the
tendon hooks on the pterygoid hamulus).
Nerve supply: Nerve to medial pterygoid
from main trunk of mandibular nerve.
Action: It tenses the soft palate.
Levator Palati
Origin: 1. Inferior surface of the petrous
part of the temporal bone.
2. Lower surface of auditory tube
Insertion: Palatine aponeurosis.
Nerve supply: Pharyngeal plexus
(cranial part of accessory nerve).
Action: It elevates the soft palate.
Maxillary nerve
One of the divisions of the trigeminal nerve
It is a pure sensory nerve.
It passes in the lateral wall of the cavernous sinus.
Then leaves the skull through foramen rotundum to
enter the pterygopalatine fossa.
It curves laterally through the pterygomaxillary fissure
to lie deep in the infratemporal fossa.
Through the inferior orbital fissure, it enters the floor of
the orbit and continues as infraorbital nerve, which
runs in the infraorbital groove, canal then foramen and
terminates in the face.
Branches
From of maxillary nerve:
1. Meningeal branch: supplies the dura of the
middle cranial fossa.
2. Two ganglionic branches: which hang the
sphenopalatine ganglion, they contain sensory
fibers coming from nose, palate and pharynx
and postganglionic fibers going to the lacrimal
gland.
3. Zygomatic branch: arises in the
pterygopalatine fossa and enters the orbit
through the inferior orbital fissure. It divides into
zygomatico-temporal and zygomatico-facial
branches that supply skin of the face.
Branches
4. Posterior superior alveolar nerve: arises
in the pterygopalatine fossa and pierces the
posterior surface of the maxilla to supply
the maxillary sinus, the upper molar teeth
and adjoining parts of the gum and cheek.
From of infraorbital nerve:
5. Middle superior alveolar nerve: arises in
the infraorbital groove and descends on the
lateral wall of the maxillary sinus to supply
the upper premolar teeth and adjoining
parts of the gum and cheek.
Branches
6. Anterior superior alveolar nerve:
arises in the infraorbital canal and
descends on the anterior wall of the
maxillary sinus to supply the upper
canine and incisor teeth and adjoining
parts of the gum and a small part of the
lateral wall and floor of the nasal cavity
7. Terminal Branches in the face: after its
exit through the infraorbital foramen it
divides into palpebral, nasal and labial
branches which supply skin of the face.
Sphenopalatine ganglion
1.
2.
3.
A parasympathetic ganglion which lies in the pterygopalatine
fossa, hanged by two roots from the maxillary nerve.
Roots:
Preganglionic Parasympathetic root: from the lacrimal
nucleus (in the brain stem), to the facial nerve which gives the
greater petrosal nerve which enters the pterygoid canal, unites
with the deep petrosal nerve to form the nerve of pterygoid canal
which joins the ganglion from its posterior aspect where they
relay inside the ganglion and gives postganglionic branches.
Postganglionic Sympathetic root: from the deep petrosal
nerve which is a branch from the internal carotid nerve in the
foramen lacerum (the sympathetic plexus around the internal
carotid artery from the upper deep cervical sympathetic
ganglion). The deep petrosal nerve unites with the greater
petrosal nerve to form the nerve of pterygoid canal (vedian
nerve).
Two Sensory roots: from the maxillary nerve.
Sphenopalatine ganglion
1.
2.
3.
4.
5.
6.
Secretomotor Branches:
To the lacrimal gland: through the maxillary
nerve  zygomatic branch  zygomaticotemporal branch  communicates with the
lacrimal nerve  the lacrimal gland.
To the mucous glands of the nose, palate.
Sensory Branches from the maxillary nerve to
the nose, palate, pharynx and orbit :
Orbital branches: through the inferior orbital
fissure.
Greater and lesser palatine nerves.
Nasal branches.
Pharyngeal branches.
Pterygopalatine fossa
Boundaries:
–
–
–
–
Anterior: posterior surface of maxilla.
Posterior: pterygoid process.
Medial: perpendicular plate of palatine bone.
Lateral: infratemporal fossa (through
pterygomaxillary fissure).
Contents:
1. Maxillary nerve and branches.
2. Sphenopalatine ganglion and branches.
3. 3rd part of maxillary artery and branches.
Pterygopalatine fossa
Communications:
1. Ptergomaxillary fissure  infratemporal
fossa.
2. Foramen rotundum  middle cranial
fossa.
3. Sphenopalatine foramen  nasal cavity.
4. Inferior orbital fissure  orbital cavity.
5. Greater palatine canal  palate.
6. Palatinovaginal canal  nasopharynx.
7. Pterygoid canal  foramen lacerum.