Trigeminal nerve

1. ANATOMY OF
TRIGEMINAL NERVE
DR MESHWA OZA
RESIDENT ENT DEPARTMENT

2.  Fifth cranial nerve (trigeminal nerve) is the largest cranial nerve.
 It comprises three branches, two of which are purely sensory and third, the
largest branch is mixed nerve.
 Trigeminal nerve is the nerve of first brachial arch

5.  Branches of this nerve provide sensory fibres to the four parasympathetic
ganglia associated with cranial outflow of parasympathetic nervous
system.
 These are ciliary, pterygopalatine, otic and submandibular

6. Nuclear Columns
1 General somatic afferent column: This column has three
nuclei. These are:
a. Spinal nucleus of V nerve: Fibres conveying pain
and temperature sensations from most of the face
area relay here (Fig. 4.26).
b. Principle sensory nucleus of V nerve: Fibres carrying
touch and pressure relay in this nucleus.
c. Mesencephalic nucleus: This nucleus extends in the
midbrain. It receives proprioceptive impulses
from muscles of mastication, temporomandibular
joint and teeth.
2 Branchial efferent column: The nucleus of V nerve is
situated at the level of upper pons. The fibres of the
motor nucleus supply eight muscles derived from
first branchial arch

7.  Sensations of pain, temperature, touch and pressure from skin of face,
mucous membrane of nose, most of the tongue, paranasal air sinuses
travel along axons.
 Ophthalmic nerve fibres end in the inferior part, maxillary nerve fibres end
in the middle part and mandibular nerve fibres terminate in the upper part
of spinal nucleus.

9. Motor Component for the Muscles
 Fibres of motor root supply four muscles of mastication temporalis,
masseter, lateral pterygoid and medial pterygoid . and four other muscles
which are tensor veli palatini, tensor tympani, mylohyoid and anterior belly
of digastric.

10. Branches of Trigeminal Nerve
 Cranial nerve V/trigeminal nerve comprise three branches—ophthalmic
V1, maxillary V2 and mandibular V3

12. Ophthalmic Nerve Division (Sensory)
 Frontal
 1 Supratrochlear: Upper eyelid, conjunctiva and lower part of forehead.
2 Supraorbital: Frontal air sinus, upper eyelid, forehead and scalp till vertex.

13. Nasociliary
1 Long ciliary: Sensory to eyeball.
2 Branch to ciliary ganglion.
3 Posterior ethmoidal: Sphenoidal air sinus, posterior
ethmoidal air sinuses.
4 Anterior ethmoidal:
a. Middle and anterior ethmoidal sinuses
b. Medial internal nasal
c. Lateral internal nasal
d. External nasal: Skin of ala of vestibule and tip of
nose.
5 Infratrochlear: Both eyelids, side of nose, lacrimal
sac

14.  Lacrimal

 Lateral part of upper eyelid; conveys secretomotor fibres from zygomatic
nerve to lacrimal gland.

15. Maxillary Nerve Division (Sensory)
It is sensory and gives branches as follows:
In Middle Cranial Fossa
Meningeal branch
In Pterygopalatine Fossa
1 Ganglionic branches
2 Zygomatic:
a. Zygomaticotemporal
b. Zygomaticofacial
3 Posterior superior alveolar

16. In Infraorbital Canal
1 Middle superior alveolar
2 Anterior superior alveolar
On Face
Infraorbital
a. Palpebral
b. Labial
c. Nasal
}
Sensory
}
Sensory

17. Mandibular Nerve Division (Sensory
and Motor)
It is a mixed nerve and its branches are:
From Trunk
1 Meningeal
2 Nerve to medial pterygoid supplies:
a. Tensor veli palatini
b. Tensor tympani
c. Medial pterygoid.

18. From Anterior Division
1 Deep temporal
2 Lateral pterygoid
3 Masseteric
4 Buccal—skin of cheek

19. From Posterior Division
1 Auriculotemporal (Fig. 4.29):
a. Auricular
b. Superficial temporal
c. Articular to temporomandibular joint
d. Secretomotor to parotid gland.
2 Lingual—general sensation from anterior two-thirds
of tongue.
3 Inferior alveolar—lower teeth, mental for skin of chin
and nerve to mylohyoid which also supplies:
a. Mylohyoid
b. Anterior belly of digastric.