FACIAL & TRIGEMINAL NERVE 2

GUIDED BY:
Dr.Adarsh Desai.
Dr.Ravi Kalola.
PREPARED BY:
Aswathi Krishna.

MANDIBULAR
NERVE V3
Trigeminal
Ganglion
Ophthalmic
Nerve V1
Maxillary
Nerve V2

 The trigeminal nerve is the largest of the twelve cranial
nerves.
 It has mainly 3 branches(Ophthalmic V1, Maxillary V2
and Mandibular V3) .
 It is composed of small motor nerve and large sensory
nerve.
 The 3 nerves arise from a large Semilunar (OR
Gasserian) Trigeminal Ganglion.
 The motor root supplies the muscles of mastication and
other muscles in the region.
 The sensory root supply the skin of the entire face and
the mucous membrane of the cranial viscera and oral
cavity, except for the pharynx and base of the tongue.

Brainstem
nuclei of
Trigeminal nerve
Semilunar
Trigeminal
ganglion
Ophthalmic
division of
Trigeminal
nerve (V1)
Maxillary
division of
Trigeminal
nerve (V2)
Mandibular
division of
Trigeminal
nerve (V3)

MOTOR ROOT
1. It consists of fibres that have their origin in
2. In the motor nucleus located in the upper pons.
3. it passes below to the foramen ovale , through
4. which it passes to join the mandibular division
5. Immediately below the base of the skull.
6. Supplies : muscles of mastication.

 The sensory root fibres of the trigeminal nerve arise
from the semilunar ganglion .
 Two ganglia are present, they are located in Meckel’s
cavity, on the anterior surface of the petrous portion of
the temporal bone.
 The ganglia are flat and crescent shaped.
 The central branches leave the semilunar ganglion and
pass back and enter the pons , where they divide into
ascending and descending fibres.
 1.Ophthalmic Division (V1)->Travels anteriorly in the
lateral wall of the cavernous sinus to the medial part of
the superior orbital fissure, through which it exits the
skull into the orbit.

 2.Maxillary Division (V2)->Travels anteriorly and
downward to exit the cranium through the foramen
rotundum into the upper portion of the pterygopalatine
fossa.
 3.Mandibular Division (V3)->Travels almost directly
downward to exit the skull, along with the motor root,
through the foramen ovale.These two roots then
intermingle, forming one nerve trunk that enters the
infratemporal fossa.
 On exiting the cranium through their respective
foramen, the three divisions of the trigeminal nerve
divide into multitude of branches.

•The ophthalmic division is the first branch of the trigeminal
nerve.
•The ophthalmic nerve arise from the semilunar ganglion in the
middle cranial fossa.
•It is the smallest of the three division.
•The ophthalmic nerve passes forward in the lateral wall of
the cavernous sinus and leaves the anterior medial part of
the ganglion.
•It divides into:
1-Frontal
2- Lacrimal
3-Nasociliary nerves

1. Frontal nerve :
-Passes forward on the superior surface of the levator
palpebrae superioris
• Divides into the:
A-Supraorbital nerve
-largest branch of the frontal nerve.
• passes forward and leaves the orbit through the
supraorbital foramen.
•Supplies the skin of upper eyelid , forehead, and
anterior scalp region to the vertex of the skull.
B-Supratrochlear nerve
-Smallest branch of frontal nerve
- Supplies : skin of the lower and medial forehead,skin
of medial aspect of upper eyelid, conjunctiva.

2. Lacrimal Nerve
• It is the smallest of three branches .
• It passes into the orbit at the lateral angle of the
superior orbital fissure .
• It supplies to lacrimal gland

3. Naso-Cilliary Nerve
•Enters the orbit through
superior orbital fissure.
• It Passes medially
above the optic nerve.
•It gives 5 branches
(a)long
(c)Nerve to ciliary ganglion
(d)Infratrochlear -> both eyelids, side of nose, lacrimal sac.
(e)Anterior ethmoidal -> Middle and anterior ethmoidal sinuses,
Medial internal nasal, Lateral internal nasal, External nasal to
skin of ala of vestibule and tip of nose.

Brainstem
nuclei of
Trigeminal nerve
Semilunar
Trigeminal
ganglion
Ophthalmic
division of
Trigeminal
nerve (V1)
Maxillary
division of
Trigeminal
nerve (V2)
Mandibular
division of
Trigeminal
nerve (V3)
Maxillary Nerve = V2

 The maxillary division of the trigeminal nerve is entirely sensory in
function.
 The maxillary nerve originates at the middle of the semilunar ganglion and
continues forward in the lower part of the cavernous sinus.
 It then passes to foramen rotundum through which it leaves the cranial
fossa and enters the pterygopalatine fossa.
 It enters the inferior orbital fissure to pass into orbital cavity.Here it turns
laterally in a groove on the orbital surface of maxilla, called the
infraorbital groove.
 Continuing forward, the second division emerges on the anterior surface of
the maxilla through the infraorbital foramen, where it divides.
 In its course from the semilunar ganglion, the maxillary division gives off
branches in four regions.
1)Middle Cranial Fossa
2)Pterygopalatine Fossa
3)Infraorbital Groove And Canal
4)On The Face (Terminal Branches)

 A small branch, The Middle Meningeal Nerve, passes
with the middle meningeal artery and its branches to
supply the dura with sensory fibers.

A)ZYGOMATIC NERVE
 The zygomatic nerve leaves the second division in the
pterygopalatine fossa and passes anteriorly and laterally
through the inferior orbital fissure into the orbit.
 Here it divides into two parts:
1)Zygomaticofacial Nerve: Passes forward on the lateral
orbital foramen and pierces the orbicularis oculi muscle.
Supplies-:Sensory fibers to the skin over the prominence
of the zygomatic bone.
2)Zygomaticotemporal Nerve: It leaves the orbit between
the great wing of the sphenoid and the zygomatic bone to
enter the temporal fossa.
Supplies-: Sensory fibers to the skin over the anterior
temporal fossa region.

B)Pterygopalatine (Sphenopalatine) Nerves
 These are two short nerve trunks that unite at the
pterygopalatine ganglion and are then redistributed into
several branches.
 These nerves also serve as important functional
communications between the ganglion and the maxillary
nerve.
 Postganglionic secretomotor fibers from the
pterygopalatine ganglion pass by means of these nerves
back along the maxillary nerve to the zygomatic nerve,
through which they are routed to the lacrimal nerve and
the lacrimal gland.
 The branches of pterygopalatine nerves are divided into
three groups:
1)Orbital
2)Nasal
3)Palatine

1)Orbital Branches
It supplies the periosteum of the orbit ,and the mucous membrane .n
2)Nasal Branches : In nasal cavity, branches divide into:
A.Posterior Superior Lateral Nasal Branches : These branches transmit
sensory impulse from the mucous membrane of nasal septum and posterior
ethmoid cells.
B.Medial Or Septal Branch : This branch passes downward and forward. It
transmits sensory impulses from the mucous membrane over the vomer. It
then descends in the incisal canal and ramifies in the mucous membrane of
the premaxillary region of the hard palate.
3)Palatine Branches : It descend in the pterygopalatine canal, where the
fibers usually divide into three parts.
A.Greater Or Anterior Palatine Nerve : Emerges on hard palate by passing
through greater palatine foramen and course in anterior direction between
hard palate and mucoperiosteum to Supply Major part of of hard palate and
palatine gingivae.
B.Middle Palatine Nerve : Emerges from lesser palatine foramen. Its fibers
are sensory to mucous membrane of soft palate.
C.Posterior Palatine Fibers : Emerging from lesser palatine foramen, goes to
mucous membrane of tonsillar area as part of sensory supply to tonsil
itself.

C)Posterior Superior Alveolar Branches:
 Two or three branches leave maxillary division just before
it enters inferior orbital fissure.
 They pass downward and continue on posterior surface of
maxilla.
 In the bone, the nerve passes down the posterolateral
wall of maxillary sinus, giving off sensory fibers to mucous
membrane of sinus. It then supplies maxillary molars and
their gingivae.
 Within the depths of alveoli, or tooth sockets, some nerve
filaments pass to supply the periodontal membranes;
whereas others, pulpal fibers, pass through apical
foramina of roots of the molar teeth to supply the dental
pulps.

 The nerve in the infraorbital groove and canal known as the
infraorbital nerve and gives off two branches.
1)Middle Superior Alveolar Nerve : Within mucous membrane of
maxillary sinus it join with other alveolar nerves and form
superior dental plexus of nerves.
The site of origin of these nerve varies from posterior portion
of infraorbital canal to anterior portion, near infraorbital
foramen.
The nerve provides sensory innervation to 2 maxillary
premolar and, perhaps, to mesiobuccal root of first molar and
periodontal tissues, buccal soft tissue, and bone in premolar
region.
2)Anterior Superior Alveolar Nerve : A relatively large branch
descend within anterior wall of maxillary sinus, it provides
pulpal innervation to central and lateral incisors and canine,
and sensory innervation to periodontal tissues, buccal bone,
and mucous membranes of these teeth.

 As infraorbital nerve is about to emerge from infraorbital
foramen on front of maxilla, it divides into 3 terminal
nerve branches.
1)Inferior Palpebral Branches: two or three in number ,
the branches pass upward.
Supplies: Sensory fibers to skin of lower eyelid and its
conjunctiva.
2)External Or Lateral Nasal Branches:The external or
lateral nasal branches pass to the skin of side of nose.
3)Superior Labial Branches:Usually two or three in number,
the branches are distributed to the skin and mucous
membrane of the upper lip.

 The Mandibular Division of trigeminal nerve is the largest
of threedivisions.
 It is formed by union of Large Sensory(Afferent) bundle of
fibers and a Small Motor(Efferent) bundle of fibers.
 The sensory root fibers are peripheral extensions of
unipolar cells located in the semilunar ganglion.
 The motor root fibers are derived from motor cells
located in medulla oblongata in middle cranial fossa
 The branches of Mandibular Division May be divided into 2
groups.
1)Branches from Undivided Nerve
2)Branches from Divided Nerve {Anterior And Posterior
Division}

A)Nerve Spinosus : Arise outside the skull and then passes
into middle cranial fossa.
Supplies: Dura And The Mastoid Cells.
B)Nerve To Internal Pterygoid Muscle : A branch of motor
root passes to innervate the internal pterygoid muscle.
This branch passes without interruption to innervate The
Tensor Veli Palatini And The Tensor Tympani Muscles.

GSA
GSA
GSA
SVE
SVE
*
*
** tensor tympani &
tensor palati
SVE

 Below the level of Undivided part of Mandibular Division, the trunk
separates into 2 parts: Anterior And Posterior Divisions.
A)Anterior Dision : It is smaller than posterior division. It passes
downward and forward, where it divided into four branches.
1.Pterygoid Nerve : It enters the medial side of external pterygoid
muscle to provide its motor nerve supply.
2.Masseter Nerve : It passes above the external pterygoid to traverse
the mandibular notch and enter the deep side of masseter muscle.
3.Nerve To The Temporal Muscle:
(a)Anterior Deep Temporal Nerve : It passes upward and crosses the
infratemporal crest of sphenoid bone. It ends in the deep part of the
temporal muscle.
(b)Posterior Deep Temporal Nerve :It passes upward to deep part of
the temporal muscle.

4.Buccal Nerve : It passes downward, anteriorly and laterally
between 2 heads of external pterygoid muscle.
•At the level of occlusal plane of mandibular second and third
molars, it divides into several branches that divide on buccinator
muscle.
•It then sends Sensory fibers to mucous membrane of cheek
region.
Others Sensory fibers pass into the retromolar triangle, providing
sensory innervation to buccal gingiva of mandibular molars and
mucobuccal fold in that region.
•The Buccal Nerve Does Not Innervate Buccinator Muscle (By
Facial Nerve)
•Almost entire mucosa of cheek is supplied by buccal nerve.

B)Posterior Division : The larger posterior division is
mainly sensory but also carries some motor
components.
This division extends downward and medially and
then divided into 3 branches.
1.Auriculotemporal Nerve
2.Lingual Nerve
3.Inferior Alveolar Nerve

1.Auriculotemporal Nerve : The nerve arises by
medial and lateral root which embrace the middle
meningeal artery and unite behind the artery just
below foramen spinosum.
The united nerve passes posteriorly, deep to external
pterygoid muscle, and then between the
sphenomandibular ligament and neck of condyle of
the mandible.
It traverses the upper deep part of parotid gland or
its fascia and then crosses the posterior root of
zygomatic arch.
It passes with superficial temporal artery in its
upward course and divide into numerous branches, to
the tragus of pinna of external ear, to scalp about ear,
and as far upward as vertex of skull.

 Branches Of Auriculotemporal Nerve : 5 branches
1>Parotid Branches : As the nerve passes the parotid gland,
it gives off sensory, secretory, and vasomotor fibers to
gland.
2>Articular Branches : 1 or 2 twigs of sensory fibers pass
from auriculotemporal nerve and enters posterior part of
Temporomandibular Joint.
3>Auricular Branches : The Anterior Auricular Branches are
usually 2. They are sensory fibers supplying skin of helix
and tragus.
4>Meatal Branches : Two small branches usually supply
skin lining meatus and tympanic membrane.
5>Terminal Branches : The major part of filaments of
auriculotemporal nerve pass to supply the scalp over the
temporal region.

LINGUAL NERVE :
1. Smaller branch 2 terminal branch of
posterior division of
mandibular nerve.
2.Passes medially to external pteryigoid muscle.
3.Lies b/w internal pterygoid muscle & ramus of
mandible.
4.Contributes sensory fibers to mucous
membrane of the floor of the mouth & gingiva
on lingual surface of ramus of mandible.

INFERIOR ALVEOLAR NERVE.
1.Largest branch of posterior division of mandibular
part of trigeminal nerve.
2.Passes downward on medial side of external pterygoid
muscle & medial side of mandibular ramus.
3.In alveolar canal it gives branches to mandibular teeth
as apical fibers.

 It is the 7th cranial nerve.
 It is the nerve of the 2nd branchial arch.

 The facial nerve is attached to the brainstem
by two roots, motor and sensory.
 The sensory root is also called the nervus
intermedius.
 The two roots of the facial nerve are
attached to the lateral part of the lower
border of the pons just medial to the eight
cranial nerve.
 The two roots run laterally and forwards,
with the 8th nerve to reach the internal
acoustic meatus.

 In the meatus, the motor root lies in a
groove on the eight nerve, with the sensory
root intervening.
 Here the seventh and eighth nerves are
accompanied by the labyrinthine vessels.
 At the bottom or fundus of the meatus, the
two roots, sensory and motor, fuse to form a
single trunk, which lies in the petrous
temporal bone.

.Within the canal the course of the nerve
can be divided into three parts by two
bends.
.The 1st part is directed laterally above the
vestibule .
.THE 2nd part runs backwards in relation to
the medial wall of the middle ear.
The third part is directed vertically
downwards behind the promontory.

 The first bend at junction of the first and
second part is sharp.
 It lies over the anterosuperior part of the
promontory , and is also called genu.
 The geniculate ganglion of the nerve is called
because it lies on the genu.
 The second bend is gradual and lies
between the promontory and the aditus to
the mastoid antrum.

 A. Within the facial canal
1.greater petrosal nerve
2.The nerve to the stapedius
3.The chorda tympani
 B. At its exit from the stylomastoid foramen .
 1. Posterior auricular
 2. Digastric
 3. stylomastoid
 C. Terminal branches within the partoid gland
 1. Temporal
 2. Zygomatic
 3. Buccal
 4. Marginal mandibular
 5. Cervical
 D. COMMUNICATING BRANCHES WITH ADJACENT CRANIAL AND SPINAL
NERVE

 1.THE NERVE TO STAPEDIUS
 It arises opposite the pyramid of middle ear.
 It supplies stapedius muscle.
 Paralysis of this muscle cause hyperacusis.
 2. CHORDA TYMPANI
 Arises in vertical part of facial canal.,about
6mm above the stylomastoid foramen.
 It enters from middle ear and runs forward in
close relation to the tympanic membrane .
 It leaves middle ear by passing through
petrotympanic fissure.
 In infratemporal fossa it joins lingual nerve.

 3. POSTERIOR AURICULAR NERVE
 Arises just below the stylomastoid foramen.
 It ascends between mastoid process and
external acoustic meatus.
 It supplies :
1. Auricularis posterior
2. 0ccipitalis
3. Intrinsic muscle on the
back of
auricle.

 4.DIGASTRIC BRANCH.
 Supplies the posterior belly of the
digastric.
 5.STYLOHYOID BRANCH.
 Arises with the digastric branch
 Supplies the stylohyoid muscle.

 6. TEMPORAL BRANCHES
 Supplies : 1. auricularis anterior
 2. auricularis posterior
 3. intrinsic muscles on the
lateral
 side of the ear
 4.frontalis
 5. orbicularis oculi
 6. corrugator supercilli

 7.ZYGOMATIC BRANCHES
 It runs across the zygomatic bone and supply the orbicularis oculi.
 BUCCAL BRANCHES : upper buccal branch
 lower buccal branch
 upper branch runs above parotid duct.
 lower branch runs below parotid duct.
 THE MARGINAL MANDIBULAR BRANCH
 Runs below the angle of mandible deep to platysma.
 It supplies muscle of lower lip and chin.


 8.CERVICAL BRANCH.
 Emerges from the apex of parotid gland
 Runs downwards and forwards in neck to
supply platysma.

 The ganglia associated with facial nerve are:
 1. The geniculate ganglion .
 2. The submandibular ganglion
 3. The pterygopalatine ganglion

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