The document discusses the maxillary and mandibular branches of the trigeminal nerve (CN V). It describes the structure, pathways, and distributions of the maxillary nerve (CN V2) and mandibular nerve (CN V3). The maxillary nerve provides sensory innervation to the maxilla while the mandibular nerve provides both sensory and motor innervation to the mandible.

1. Trigeminal nerve
The maxillary and the mandibular branches
By
Ahmed reda abdel-hameed

2. LIST OF FIGURES.......................................................................................................- 2 -
TRIGEMINAL NERVE (CN V)......................................................................................- 3 -
ABSTRACT:.................................................................................................................- 4 -
PROPRIOCEPTION OF THE TRIGEMINAL NERVE..................................................- 7 -
LESIONS OF TRIGEMINAL NERVE...................................................................................- 7 -
TREATMENT...........................................................................................................- 8 -
DIVISIONS/DISTRIBUTIONS BRANCHES..........................................................................- 10 -
MAXILLARY NERVE (CN V2)....................................................................................- 11 -
STRUCTURE..............................................................................................................- 11 -
NERVE AND FORAMENS...............................................................................................- 13 -
NERVE PATHWAY AND DISTRIBUTION:..........................................................................- 13 -
MANDIBULAR NERVE (CN V3)..................................................................................- 14 -
STRUCTURE..............................................................................................................- 14 -
NERVE AND FORAMENS...............................................................................................- 16 -
NERVE PATHWAY AND DISTRIBUTION:..........................................................................- 17 -
CLINICAL CORRELATE............................................................................................- 18 -
CONCLUSION............................................................................................................- 19 -
Maxillary division........................................................................- 19 -
Mandibular..................................................................................- 19 -
REFERENCES............................................................................................................- 23 -
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3. List of figures
FIGURE 1.2(TRIGEMINAL N LATERAL VIEW)...........................................................................- 3 -
FIGURE 1. 3(OPEN BOOK VIEW)...................................................................................................- 4 -
FIGURE 1. 4(INNERVATION ZONES)..........................................................................................- 5 -
FIGURE 1. 5(C.N.S)...........................................................................................................................- 5 -
FIGURE 1. 6(ROOTS OF TRIG N)....................................................................................................- 5 -
FIGURE 1. 7(BRANCHES)................................................................................................................- 6 -
FIGURE 1. 8(ACOUSTIC NEUROMA)..........................................................................................- 9 -
FIGURE 1. 9(MAX AND MAND DIVISIONS)..............................................................................- 10 -
FIGURE2. 1 (MAXILLARY NERVE)............................................................................................- 13 -
FIGURE3. 1 (MANDIBULAR NERVE).........................................................................................- 17 -
FIGURE4. 1(TEETH INERVATIION BY BOTH MAX AND MAND NERVES).........................- 18 -
FIGURE5. 1 (ILLU STRATED DIAGRAM SHOWS BRANCHES OF TRIGEMINAL N)............- 20 -
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4. TRIGEMINAL NERVE (CN V)
Figure 1. 1 (position)
Figure 1.2(trigeminal n lateral view)
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5. 2
Figure 1. 3(open book view)
1
Abstract:
Face Cutaneous (sensory) innervation of the face is provided primarily by
the trigeminal nerve) and the motor innervation to the muscles of
mastication by the mandibular nerve, the motor root of the trigeminal
nerve. 1
Ophthalmic n. /one
/ones of skin
Maxillary n. /oneInnervation of
li luminal nerve
divisions, where
pain may occur
In trigeminal
( omrttoiilunu.ilgla
trigger points
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6. Figure 1. 4(innervation zones)
Oculomotor nerve
Spinal accessory
Figure 1. 6(roots of trig n)
The trigeminal nerve is considered to be one of the cranial nerves.
Cranial nerves or cerebral nerves:
Optic nerve (CNII)
Lobes and structures
Frontal lobe(CN 111)
‘’.in- * * 1 :vestibulocochlear
Trochlear nerve Temporal lobenerve (CN VIII)
C Occipital lobe
Cttn in
nerve
DMOMN MGkMophaiynged
HniiMeninerve (CN IX)
MidbrainAbducent neive
(CN VI)
Vagus nerve (CN X) Medulla (oblongata)
Facial nerve
(CN VII)
nerve (CN XI) Hypoglossal nerve
Figure 1. 5(C.N.s)
They are those peripheral nerves that leave the brain or brainstem
the cranial nerves customarily are subdivided into 12 pairs:
I: Olfactory nerve II:
Optic nerve III:
Oculomotor nerve IV:
Trochlear nerve V:
Trigeminal nerve VI:
Abducens nerve
VII: Facial nerve
VIII: Vestibulocochlear nerve
IX: Glossopharyngeal nerve
X: Vagus nerve
XI: Spinal accessory nerve
XII: Hypoglossal nerve
Because of the high degree of differentiation in the brain of humans,
cranial nerves are more complex in structure and function than spinal
nerves
The trigeminal nerve (CN V)
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7. Emerges from the lateral aspect of the pons by a large sensory root and
a small motor root. CN V is the principal general sensory nerve
for the head (face, teeth, mouth, nasal cavity, and dura of the cranial
cavity). The sensory root of CN V is composed mainly of the central
processes of neurons in the trigeminal ganglion. The peripheral processes
Figure 1. 7(branches)
The trigeminal nerve (CN V) is the sensory nerve for the face and the
motor nerve for the muscles of mastication and several small muscles
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8. TRIGEMINAL NERVE PATHWAYS
Responsible for carrying to conscious level:
• Pain rind temperature
• 1 iglit lour h
• Discriminative ninth
• lYessure
Utilizes a 3 neuron sensory system:
• Primary neuron
• Serin ulary neuron
• Tertiary neuron
Utilizes the contralateral ventral ingommolhalamir tract
Same discriminative loudi and pressure libers utilize the ipsi lateral dorsal triftiminolhalamii 1rnt 1. but
this contribution is very minor
Pniprkxepifon tillers are unique in that the cell body for the sensory nerve fiber is located in the central
nervous system (mesencephalic nuceus) '
Types of Fibers Trigeminal Sensory Nucleus Ascending Pathway
Pam and temperature [
ighi louch
Spinal (descending) nucleus Vi'iiir.il triftUTiinotlialamir trad
Discriminative touch
f,res5ure
(Vincipal (main) sensory
nucleus Ventral trigeminothalamic trad (Dorsal
trigemino thal anit 1 racl subserves
discriminative touch and pressure)
Proprioception Mesencephalic nucleus
Projects to niuicir nucleus of v to control the
jaw jerk reflex and force {>1 bite
PROPRIOCEPTION OF THE TRIGEMINAL NERVE
Sensory fibers carry input from the neuromuscular spindles along
the mandibular division of the trigeminal n. The nerve cell bodies of these
sensory neurons are located in the mesencephalic nucleus of the midbrain
These fibers project to the motor nucleus of the trigeminal n. innervate the
muscles of mastication, to control the jaw jerk reflex and force of bite.
Lesions of Trigeminal Nerve
Lesions of the entire trigeminal nerve cause widespread anesthesia
involving the
• Corresponding anterior half of the scalp
• Face, except for an area overlying the angle of the mandible
• Cornea and conjunctiva
• Mucous membranes of the nose and paranasal sinuses, mouth, and
anterior part of the tongue Paralysis of the muscles of mastication also
occurs.

9. TREATMENT
Commonly, trigeminal neuralgia is treated pharmacologically with
anticonvulsants, such as carbamazepine (Tegretol) if drug therapy is
unsuccessful, neurosurgery may be required, such as percutaneous
radiofrequency rhizotomy of the nerve, glycerol injection of the
trigeminal ganglion, or nerve decompression Alternative and
complementary medicine treatments have included acupuncture and
meditation.Zones of skin innervation of trigeminal nerve divisions, where
pain may occur in trigeminal neuralgia Common trigger points.
3
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10. Figure 1. 8(acoustic neuroma)
Injury to Trigeminal Nerve CN V may be injured by trauma, tumors,
aneurysms, or meningeal infections, causing • Paralysis of the
muscles of mastication, producing deviation of the mandible toward
the side of the lesion • Loss of the ability to appreciate soft tactile,
thermal, or painful sensations in the face • Loss of the corneal reflex
(blinking in response to the cornea being touched) and the sneezing
reflex Trigeminal neuralgia (tic douloureux), the principal disease
affecting the sensory root of CN V, produces excruciating, episodic
pain that is usually restricted to the areas supplied by the maxillary
and/or mandibular divisions of CN V.
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11. Divisions/Distributions Branches
Three large groups of peripheral processes from nerve cell bodies of the
trigeminal ganglion—the large sensory ganglion of CN V—form the
ophthalmic nerve (CN V1), the maxillary nerve (CN V2), and the sensory
component of the mandibular nerve (CN V3). These nerves are named
according to their main regions of termination: the eye, maxilla, and
mandible, respectively. The first two divisions (CN V1 and CN V2) are
totally sensory. CN V3 is different as it mostly sensory but also receives
motor fibers from the CN V. The major cutaneous branches of the
trigeminal nerve are
• Ophthalmic nerve (CN V1): lacrimal, supra-orbital, supratrochlear,
infratrochlear, and external nasal nerves
• Maxillary nerve (CN V2): infra-orbital, z ygomaticotemporal, and
zygomaticofacial nerves
• Mandibular (CN V3): auriculotemporal, buccal, and mental nerves.
From the anterior border of the trigeminal ganglia, the three terminal
branches of the trigeminal n arise which in the correct descending order
are:
• The Ophthalmic nerve (CN V1)( This is not our main concern for
now)
• The maxillary nerve (CN V2)
• The Mandibular nerve (CN V3)
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12. Maxillary nerve (CN V2)
Structure
MAXILLARY DIVISION OT THE TRIGEMINAL NERVE 9<
The maxillary division (V;), being a liraiu.li of (he trigeminal n., is sensory in function Branches tram the trigeminal n. and travels
along the lateral wall of the cavernous sinus Passes from Ihe middle cranial fossa into the pterygopalatine fossa via the* foramen
rotundum Within the pterygopalatine fossa, it gives rise to a branches
t of those nerves, the infraorbital n„ is considered the continuation of the maxillary division of the trigeminal n.
BRANCHES WITHIN Till. MIDDLE CRANIAL IOSSA
Nerve Course
Meningeal
A small meningeal branch is given off within the middle cranial fossa Tile nerve supplies the meninges
BRANCHES WITHIN THE PTERYGOPALATINE IOSSA
Nerve Course
Posterior superior
alveolar
Passes through the pterygomaxillary fissure to enter the infratemporal fossa
In the infratemporal fossa, it passes on the posterior surface of the maxilla along the region of the
maxillary tuberosity
Gives rise to a gingival branch that innervates the buccal gingiva alongside (tie maxillary molars
Enters the posterior surface of the* maxilla and supplies the maxillary sinus and the maxillary molars,
with the possible exception of the mesiobuccal root ol t(»e 1st maxillary molar, and the gingiva ancf
mucosa alongside the* same teetfi
Zygomatic
Passes through the inferior orbital fissure to enter the orbit Passes on the lateral wall of the orbit and
branches into the zygomaticotemporal and zygomaticofacial branches
A communicating branch from it joins the lacrimal n. from the ophthalmic division of the trigeminal n.
to carry autonomies to the lacrimal gland
Ganglionic
branches
Usually 1 or z ganglionic brandies that connect the maxillary division of ttie trigeminal n. to trie
pterygopalatine ganglion Contain sensory fibers that pass through trie pterygopalatine ganglion
(without synapsing) to be distributed with the* nerves llial arise from the pterygopalatine ganglion
Also contain postganglionic autonomic fibers to the lacrimal gland that pass through the
pterygopalatine ganglion (parasympathetic libers form a synapse here between the preganglionic
libers from the vidian n. and the postganglionic fibers)
Infraorbital Considered the continuation of the maxillary division of the trigeminal n. Passes through the inferior
orbital fissure to enter Ihe odnt Passes anlenorly through the infraorbital groove and infraorbital canal
and exits onto the face via the infraorbital foramen
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13. BRANCHES ASSOCIATED WITH THE PTERYGOPALATINE GANGLION
Nerve Course
Posterior inferior nasal
branch of the
greater palatine
While descending in the palatine canal, the greater palatine n. gives rise to a posterior infenor
nasal branch
Supplies the posterior part of the lateral wall of the nasal cavity in the region of the middle
meatus
Lesser palatine
Passes through the palatine canal to enter and supply the soft palate via the lesser palatine
foramen
Nasopalatine
Branches from the pterygopalatine ganglion in the pterygopalatine fossa Passes through the
sphenopalatine toramen to enter the nasal cavity Passes along the superior portion of the nasal
cavity to the nasal septum, where it travels anteroinleriorly to the incisive canal, supplying the
septum Passes through the incisive canal to supply the gingiva ana mucosa of the hard palate
from central incisor to canine
BRANCHES WITHIN THE INFRAORBITAL CANAL
Nerve Course
Middle superior
alveolar
A variable nerve
When present, it branches off the infraorbital n. as it travels in the infraorbital canal
As the nerve descends to form the superior dental plexus, it innervates part of the maxillary
sinus; the premolars and possibly the mesiobucca! root of the 1st molar; and the gingiva and
mucosa alongside the same teeth
Anterior superior
alveolar
While in the infraorbital canal, it gives rise to the anterior superior alveolar a, which has a small
branch that supplies the nasal cavity in the region of the inferior meatus and inferior
corresponding portion of the nasal septum, the maxillary sinus
As the nerve descends to form the superior dental plexus, it innervates part of the maxillary
sinus; maxillary central incisor, lateral incisor, and canine teeth; and the gingiva and mucosa
alongside the same teeth
BRANCHES A ITER INFRAORBITAL NERVE. EMERGES FROM THE INFRAORBITAL FORAMEN
Nerve Course
Superior labial branch of the
infraorbital
Supplies the skin of the upper lip
Nasal branch of the infraorbital Supplies the ala of the nose
Inferior palpebral branch of the
infraorbital
Supplies the skin of the lower eyelid
Somatic sensory only passes through foramen rotundum Supplies dura
mater of anterior part of middle cranial fossa; conjunctiva of the lower
part of eyelid; mucosa of postero-inferior nasal cavity, maxillary sinus,
anterior part of superior oral vestibule, and palate; upper teeth; and
skin of lateral external nose, inferior eyelid, anterior cheek, and upper
lip
Meningeal branch Zygomatic nerve Zygomaticofacial branch
Zygomaticotemporal branch Communicating branch to lacrimal nerve
Ganglionic branches to sensory root of pterygopalatine ganglion Posterior
superior alveolar branches Infra-orbital nerve Anterior and middle
superior alveolar branches Superior labial branches Inferior palpebral
branches External nasal branches Greater palatine nerves Posterior
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14. inferior lateral nasal nerves Lesser palatine nerves Posterior superior
lateral nasal branches Nasopalatine nerve Pharyngeal nerve.6
Nerve and foramens
Nerve pathway and distribution:
Figure2. 1(maxillary nerve)
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15. Mandibular nerve (CN V3)
Structure
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16. POSTERIOR DIVISION OF THE MANDIBULAR NERVE
Blanch Course
Auriculolem
poral
Normally arises by 1 roots, between which the middle
iMitgeal a, passes Runs posteriorly jusl inferior lo the
lateral pterygoid and continues to Ihe medial side ol the
neat of Ihe mandible
Then it turns superiorly with the superficial temporal
vessels between the auricle and condyle of tfie mandible
deep to the parotid gland On eating tne parotid gland ft
ascends over the zygomatic arch and divides into superlicial
temporal branches
Lingual Lies inferior lo Ihe lateral pterygoid and medial and
anterior lo the inferior alveolar n. Ihe chorda tympani n.
also joins the posterior pari Ihe lingual n, passes between
the medial pterygoid and the ramus ol the mandible to
pass obliquely lo enter the oral cavily bounded by the
superior pharyngeal constrictor m, medial pterygoid, and
the mandible Supplies the mucous membrane of Ihe
anterior 2/3 ol the tongue and gingiva on the lingual side
ol the mandibular leeth
Inferior
alveolar
Hie largest branch of ihe mandibular division Descends
following the inferior ai™iar a. inferior to ihe lateral
pterygoid and finally between the spnenomandfcjlar lig.
and the ramus ol tiw mandible until it
enters the mandibular Intamen
Innervates all mandibular teeth and ihe gingiva from ihe
premolars anteriorly to Ihe midline via tire menial
branch
Mylohyoid Brandies from the inferior alveolar n. immediately before it
enters the mandibular foramen
Descends jn a groove on the deep side of the ramus of the
mandible until it reaches the superficial surface of lie
mylohyoid Supplies the mylohyoid and the anterior belly of
the digastric m.Somatic sensory and somatic (branchial) motor Passes through the
foramen ovale supplies sensory innervation to mucosa of anterior two
thirds of tongue, floor of mouth, and posterior and anterior inferior oral
vestibule; mandibular teeth; and skin of lower lip, buccal, parotid, and
temporal regions of face; and external ear (auricle, upper external
auditory meatus, and tympanic membrane) Supplies motor innervation to
muscles of mastication, mylohyoid, anterior belly of digastric, tensor
tympani, and tensor veli palatini.
Somatic sensory branches meningeal branch (nervus spinosum) Buccal
nerve Auriculotemporal nerve Lingual nerve Inferior alveolar nerve
Inferior dental plexus mental nerve Somatic (branchial) motor branches
to: Masseter Temporalis Medial and lateral pterygoids Mylohyoid
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17. Anterior belly of digastric Tensor tympani Tensor veli palatini of the
ganglionic neurons form three nerves or divisions are the ophthalmic
nerve (CN V1), maxillary nerve (CN V2), and sensory component of the
mandibular nerve (CN V3). For a summary of CN V. The fibers of the
motor root of CN V are distributed exclusively via the mandibular nerve
(CN V3) to the muscles of mastication, mylohyoid, anterior belly of the
digastric, tensor veli palatini, and tensor tympani.
Receives the motor root of the trigeminal nerve (CN V) and descends
through the foramen ovale to enter the infratemporal fossa, dividing into
anterior and posterior trunks. The branches of the large posterior trunk are
the auriculotemporal, inferior alveolar, and lingual nerves. The smaller
anterior trunk gives rise to the buccal nerve and branches to the four
muscles of mastication (temporalis ,Masseter, and medial and lateral
pterygoids) but not the buccinator, which is supplied by the facial nerve
(CN VII).
Nerve and foramens
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18. Nerve pathway and distribution:
Sensory root
Motor root
Nerve to medial pterygoid
Trigeminal ganglion
Otic ganglion
Tensor tympani
Tensor palati
Medial pterygoid
Nervus spinosus
Masseteric nerve
Auriculotemporal nerve
Deep temporal nerves
Buccal nerveMiddle meningeal artery
Nerve to lateral pterygoid
Lingual nerve
Chorda tympani nerve
Inferior alveolar nerve
Submandibular duct
Incisive brancha nerve
Nerve to mylohyoid muscle Mental nerve
Nerve to anterior belly of digastric muscle
Figure3. 1(mandibular nerve)
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19. Clinical Correlate
Dental clinical relation for mandibular and maxillary nerves
Figure4. 1(teeth inervatiion by both max and mand nerves)
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20. Conclusion
The trigeminal nerves
• It is considered as mixed nerve motor and sensory.
• It is the largest and most complex of the cranial nerves.
• The trigeminal nerve is emerges from the pons and divides into
ophthalmic maxillary and mandibular nerves (divisions that receive
sensory supply from the face with an exception of a small area over
the ramus of the mandible).
• All motor fibers belong to the mandibular division and supply
muscle of the mastication
Maxillary division
The maxillary division of trigeminal nerve has a sensory function. It
transmits sensation from the:
• lower eyelid plus associated mucous membranes
• middle part of the maxillary sinuses
• nasal cavity and middle part of the nose
• cheeks
• upper lip
• The maxillary teeth plus alveolar bone and other investing
structures (anterior superior alveolar. middle superior alveolar &
posterior superior alveolar nerves).
• roof of the mouth(the palate)
Mandibular
The mandibular division is the only part of the trigeminal nerve that has
both sensory and motor functions.
It communicates sensation from the:
Page- 19 - | 23

21. • outer part of the ear
• lower part of the mouth and the associated mucous membranes
• anterior 2/3 the of tongue
• the mandibular teeth plus alveolar bone and other investing structures
• lower lip
• The chin
• The motor branches : supply the movement to 8 muscles (4 muscles
of mastication & other 4 muscles)
Maxillary
nerv
e
'’Anienor tup
alveolar
nerve
alveolar
Buccivajcular
Zygomatic
Lacnmal nerveSemilunar
nrrvrSensory rootgangnon
Motor root
Facial
MNl
Auriculotemporal 6
MTM
InfeiiD-
Posterior sup
iww avedar nerve
area
V nOh md
m
Mental nervee ve
Figure5. 1(illustrated diagram shows branches of trigeminal n)
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22. • Divisions/Distributions • Branches
• Maxillary nerve (CN V2) Somatic • Meningeal branch Zygomatic nerve
sensory only Passes through foramen Zygomaticofacial branch
rotundum Supplies dura mater of Zygomaticotemporal branch
anterior part of middle cranial fossa; Communicating branch to lacrimal
conjunctiva of inferior eyelid; mucosa nerve Ganglionic branches to (sensory
of postero-inferior nasal cavity, root of)
maxillary sinus, palate, and anterior
• pterygopalatine ganglion Posterior
part of superior oral vestibule;
superior alveolar branches Infra-
maxillary teeth; and skin of lateral
orbital nerve Anterior and middle
external nose, inferior eyelid, anterior
superior alveolar branches Superior
cheek, and upper lip
labial branches Inferior palpebral
branches External nasal branches
Greater palatine nerves Posterior
inferior lateral nasal nerves Lesser
palatine nerves Posterior superior
lateral nasal branches Nasopalatine
nerve Pharyngeal nerve
• Mandibular nerve (CN V3) Somatic • Somatic sensory branches Meningeal
sensory and somatic (branchial) motor branch (nervus spinosum) Buccal
Passes through the foramen ovale nerve Auriculotemporal nerve Lingual
Supplies sensory innervation to nerve Inferior alveolar nerve Inferior
mucosa of anterior two thirds of dental plexus Mental nerve Somatic
tongue, floor of mouth, and posterior (branchial) motor branches to:
and anterior inferior oral vestibule; Masseter Temporalis Medial and
mandibular teeth; and skin of lower lateral pterygoids Mylohyoid Anterior
lip, buccal, parotid, and temporal belly of digastric Tensor tympani
regions of face; and external ear
(auricle, upper external auditory
meatus, and tympanic membrane)
Supplies motor innervation to muscles
of mastication, mylohyoid, anterior
Tensor veli palatini
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23. References
1. Moore, Keith L., author. Essential clinical anatomy / Keith L.
Moore, Anne M.R. Agur, Arthur F. Dalley II. — Fifth edition
2. Parent text: Clinically oriented anatomy / Keith L. Moore, Arthur
F. Dalley, Anne M.R. Agur. 7th ed. c2014. Includes
bibliographical references and index
3.
https://books.google.com/books?hl=en&lr=&id=5AnZDwAAQBA
J&oi=fnd&pg=PA208&dq=Trigeminal+neuralgia+(tic+douloureux
&ots=LyuzJ63H8G&sig=XQ87s0IST48FvN3lMJuZgLx6LlQ
4. Bell WE. Orofacial Pains: Differential Diagnosis. 2nd. Year Book
Medical Publisher; 1979.
5. Agur, A. M. R., author. II. Dalley, Arthur F., II, author. III. Moore,
Keith L. clinically oriented anatomy. Digest of (work): IV. Title.
[DNLM: 1. Anatomy—Handbooks. QS 39]
6. https: //slideplayer.com/slide/12940793/
7. Agur AMR, Dalley AE. The Cranial Nerves. Grant S Atlas of
Anatomy. Baltimore: Williams & Wilkins; 2004.
8. Sooy CD, Boles R. Neuroanatomy for the Otolaryngologist Head
and Neck Surgeon. Paparella MM, and Shumrich DA.
Otolaryngology: Basic Sciences and Related Principles.
Philadelphia: WB Saunders; 1991.
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