The trigeminal nerve divides into three major branches - ophthalmic, maxillary, and mandibular nerves. These branches innervate the face and associated structures. The maxillary nerve passes through multiple foramina and fossae, supplying structures like the orbit, palate, nasal cavity and upper lip. The mandibular nerve divides into anterior and posterior branches that innervate muscles like the masseter and tissues of the lower face and oral cavity. Key ganglia like the pterygopalatine and otic relay parasympathetic fibers to glands like the parotid.

1. Temporal & Infratemporal Regions II
Dr. Prabhakar Yadav
Associate Professor
Department of Human Anatomy
B.P. Koirala Institute of Health Sciences

2. Course of the Trigeminal Nerve
• Leaves anterior aspect of the pons as
a small motor root and a large sensory
root.
• Passes forward out of the posterior
cranial fossa and rests on the upper
surface of the apex of the petrous
part of the temporal bone in the
middle cranial fossa.
• Sensory root expands to form
Trigeminal ganglion, which lies within
a pouch of dura mater called
trigeminal or Meckel cave.

3. Course of Trigeminal Nerve
• Ophthalmic, maxillary, and
mandibular nerves arise from
anterior border of the ganglion .
• V1,V2 contains only sensory
fibers and leaves skull through
superior orbital fissure &
foramen rotundum respectively
• V3 contains both sensory and
motor fibers and leaves skull
through the foramen ovale.
• V1 & V2 runs in lateral wall of
cavernous sinus.

4. V2:
• run in wall of cavernous sinus
• leave through rotundum
• enter pterygopalatine fossa
• enter orbit through inferior
orbital fissure & acquires
name- Infra orbital nerve
• leave orbit through infraorbital
foramen &
• emerge on face.
Maxillary div supply:
lower eyelid, conjunctiva, skin
of cheek, maxillary sinus mucosa,
nasal cavities mucosa, upperlip,
incisior canine & molar upper.
Superior part of palate.

5. In Midddle cranial fossa: Middle meningeal nerve
In pterygopalatine fossa: Ganglionic branch
Zygomatic ----- a. zygomaticotemporal; b.Zygomaticofacial
Posterior superior alveolar
In infraorbital canal: a. Middle superior alveolar , b.Anterior superior alveolar
On face: a. Plapebral, b. Nasal, c.Labial

6. In Middle Cranial Fossa
Meningeal branch: Supplies dura mater of middle
cranial fossa.
In Pterygo-palatine Fossa
Ganglionic branches: two in number to
pterygopalatine ganglion.

7. In Pterygo-palatine Fossa
Zygomatic nerve:
enters the orbit through inferior orbital fissure and
divides into:
(a) zygomaticotemporal branch: supply skin of temple
(b) zygomaticofacial branch: supply skin of face.
Posterior superior alveolar nerve: supplies mucus
membrane of maxillary air sinus.
Form superior dental plexus, which supplies molar
teeth & adjoining part of the gum.
superior dental plexus:
Formed by posterior,middle, and anterior superior
alveolar nerves.
Situated in alveolar process of maxilla above the
sockets of the teeth.

8. In the Orbit (infraorbital canal)
Middle superior alveolar nerve: supplies premolar
teeth.
Anterior superior alveolar nerve: divides into dental
and nasal branches:
(a) Dental branches: supply canine & incisor teeth.
(b) Nasal branches: supply mucosa of lateral wall and
floor of the nasal cavity.

9. On the Face
1. Palpebral branches: supply skin of lower eyelid
2. Nasal branches: supply skin of side of nose &
mobile part of nasal septum.
3. Superior labial branches: supply skin and mucus
membrane of upper lip.

10. MANDIBULAR NERVE :
-Largest divisions of trigeminal nerve. --
-Mixed nerve & nerve of first pharyngeal
arch.
-Sensory root arises from lateral part of
trigeminal ganglion & leaves cranial
cavity through foramen ovale.
-Motor root lies deep to trigeminal
ganglion, passes through foramen ovale
to join sensory root just below
foramen, forming the main trunk.
-Main trunk lies in infratemporal fossa,
on tensor veli palatini, deep to lateral
pterygoid.
-Main trunk divides into a small anterior
trunk & large posterior trunk

11. Mandibular Nerve:
Trunk:
1.Meningeal(Nervus-spinosus)
2. Nerve to medial pterygoid
Anterior division:
1. Masseteric
2. Deep temporal
3. Lateral pterygoid
4. Buccal
Posterior division:
1. Auriculotemporal
2. Lingual
3. Inferior alveolar
4. Nerve to mylohyoid

13. Meningeal Branch or Nervus Spinosus:
Supplies- dura mater of middle cranial foss
Nerve to Medial Pterygoid
Supplies-medial pterygoid
It gives a motor root to otic ganglion which
does not relay & supplies tensor veli palatin
& tensor tympani
Masseteric Nerve.
Supplies- masseter, temporomandibular
joint
Deep Temporal Nerves:
Supplies-temporalis.
Nerve to Lateral Pterygoid:
Buccal Nerve
supplies – skin & mucous membrane related to buccinator
- labial aspect of gums of molar & premolar teeth

14. Auriculotemporal Nerve:
Distribution:
(a) Auricular branches- skin of tragus,
upper part of pinna, external auditory
meatus & tympanic membrane.
(b) Articular branches - temporomandibular
joint.
(c) Superficial temporal branches- skin of
temple.
(d) It’ssecretomotor fibres - parotid gland.

15. Lingual Nerve
Terminal branches of posterior division of mandibular nerve.
Distribution:
(a) Provides sensory supply to floor of mouth, lingual surface of the gum and anterior two-third of tongue
(b) Carries preganglionic secretomotor fibres to submandibular & sublingual salivary glands.

16. Inferior alveolar nerve:
Larger terminal branch of posterior division of
mandibular nerve. It is a mixed nerve
Branches:
(a) Nerve to mylohyoid: It pierces sphenomandibular
ligament to reach mylohyoid groove. It supplies
mylohyoid and anterior belly of digastric muscle.
(b) Dental branches supply molar and premolar teeth.
(c) Mental nerve: supply skin of chin and skin & mucus
membrane of lower lip.
(d) Incisive branch: supplies canine and incisor teeth.

17. OTIC GANGLION:
Parasympathetic ganglion, located at
infra- temporal fossa, just below foramen
ovale.
Topographically related to mandibular
nerve but functionally related to
glossopharyngeal nerve.
It provides a relay station to the
secretomotor fibres to the parotid gland.
Relations
Lateral: Mandibular nerve.
Medial: Tensor palati muscle.
Posterior: Middle meningeal artery.
Anterior: Medial pterygoid muscle.

18. Connections and Branches:
secretomotor or Parasympathetic root:
formed by lesser petrosal nerve.
Preganglionic parasympathetic fibres arise
from inferior salivatory nucleus, passes
successively through glossopharyngeal nerve,
tympanic branch of glossopharyngeal nerve
(Jacobson’s nerve), tympanic plexus, and
lesser petrosal nerve to relay in the ganglion.
Postganglionic parasympathetic fibres from
ganglion pass through auriculo-temporal
nerve to supply parotid gland.

19. Connections and Branches:
•Sympathetic root: - vasomotor in function
• derived form plexus on middle meningeal
artery which contains post ganglionic fibres
arising in superior cervical ganglion.
•Fibres pass through otic ganglion without
relay and reach parotid gland via
auriculotemporal nerve
•Sensory root: sensory to the parotid gland-
from auriculotemporal nerve
•Somatic motor: Nerve to medial pterygoid
passes through ganglion without relay to
supply medial pterygoid, tensor palati, and
tensor tympani muscles.

20. Pterygopalatine Ganglion (Sphenopalatine Ganglion)
Ganglion of Hay fever:
•Largest parasympathetic peripheral ganglion.
Location
upper part of the pterygopalatine fossa, suspended
from maxillary nerve by two short roots.
Relations
Behind: Pterygoid canal.
Above: Maxillary nerve.
Medial: Sphenopalatine foramen.

21. •serves as a relay station for secretomotor fibres to lacrimal gland & mucus glands of nose, palate,
pharynx & paranasal sinuses.
•Topographically, related to the maxillary nerve, but functionally connected to facial nerve through
greater petrosal nerve

23. Connections:
Motor or parasympathetic root : formed by
nerve of pterygoid canal.
It carries preganglionic fibres from superior
salivatory & lacrimatory nuclei.
Preganglionic fibrs pass through facial nerve,
geniculate ganglion, greater petrosal nerve &
nerve of pterygoid canal to reach ganglion.
Postganglionic fibres arise in ganglion to
supply secretomotor nerves to lacrimal gland
and to mucous glands of the nose, palate,
pharynx & paranasal sinuses.

24. Sympathetic root: formed by nerve of
pterygoid canal.
It contains postganglionic fibres from superior
cervical sympathetic ganglion which pass
through the internal carotid plexus, deep
petrosal nerve and the nerve of the pterygoid
canal to reach the ganglion.
Postganglionic fibres pass through the
ganglion without relay and provide vasomotor
supply to the mucus membrane of the nose,
palate, pharynx, and paranasal air sinuses.

25. Sensory root: is derived from maxillary nerve and passes through the ganglion without relay to be
distributed through the branches of the ganglion.

26. Branches
Branches of the ganglion are actually branches
of the maxillary nerve. They also carry
parasympathetic and sympathetic fibres which pass
through the ganglion.
Orbital branches:
pass through inferior orbital fissure
supply - periosteum of orbit, and orbitalis muscle
Palatine branches:
Greater palatine –
pass through greater palatine canal
Supply- Hard palate & labial aspect of upper gums .
Lesser & posterior palatine nerves:
supply- soft palate & tonsil

27. Nasal branches (posterior superior nasal nerves ):
pass through sphenopalatine foramen to enter nasal
cavity.
divided into two sets- lateral and medial.
Lateral set supply lateral wall of nasal cavity
Medial set supply roof & nasal septum.
•Nasopalatine/ sphenopalatine nerve –
Longest branch of medial set.
Runs anteroinferiorly on the nasal septum and leaves
the nasal cavity through incisive foramen.
Enter oral cavity & supplies anterior part of hard
palate.
pharyngeal branch:
passes through palatovaginal canal
supply- nasopharynx.

28. Lacrimal branch: Postganglionic fibres pass
back into maxillary nerve to leave it through
its zygomatic nerve and its zygomaticotemporal nerve,
a communicating branch to lacrimal nerve to supply
secretomotor fibres to the lacrimal gland.

29. Applied Anatomy:
The allergic conditions eg. cold, cause irritation of nerve of
pterygoid canal/pterygopalatine ganglion, which causes congestion
of glands of the nose and palate, and lacrimal gland producing
running nose & lacrimation. The condition is called hay fever.
Inferior alveolar nerve block (1A block):
most common nerve block performed in dentistry to carry out
dental procedures on the mandibular teeth.
Anesthetic agent is injected slightly superior to the
entry of inferior alveolar nerve into the mandibular foramen.