Trigeminal nerve

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           TRIGEMINAL NERVE

Fifth cranial 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.






Ophtholmic Nerve Division

Ophthalmic nerve is sensory. Its branches are:
 
FRONTAL -
1). Supratrochlear: Upper eyelid,  conjunctiva, lower part of forehead.
2). Supraorbital: Frontal air sinus, upper eyelid, forehead, scalp till vertex .

NASOCILIARY -
1). Posterior ethmoidal: Sphenoidal air sinus, posterior ethmoidal air sinuses.
2). Long cilary : Sensory to eyeball.
3). Branch to ciliary ganglion.
4). Infra Trochlear: Both eyelids, side of nose, Iacrimal sac.
5). 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.

LACRIMAL -
Lateral part of upper eyelid; conveys secretomotor
fibres from zygomatic nerve to lacrimal gland.


Maxillary Nerve Division

IN MIDDLE CRANIAL FOSSA
 Meningeal branch

IN PTERYGOPALATINE FOSSA
1). Ganglionic branches
2). Zygomatic:
a. Zygomaticotemporal 
b. Zygomaticofacial 
3). Posterior superior alveolar

IN INFRAORBITAL  CANAL
1). Middle superior alveolar
2). Anterior superior alveolar

ON FACE
Infraorbital
a. Palpebral
b. Labial
c. Nasal

Mandibular Nerve Division

TRUNK
1). Meningeal
2). Nerve to medial pterygoid supplies:
a. Tensor veli palatini
b. Tensor tympani
c. Medial pterygoid.

ANTERIOR DIVISION
1). Deep temporal
2). Leteral pterygoid
3). Masseteric
4). Buccal - skin of check.

POSTERIOR DIVISION
1). Auriculotemporal :
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:
a. Mylohyoid
b. Anterior belly of digastric.


APPLIED ANATOMY

1). The superior oblique muscle innervated by the trochlear nerve helps in upward movement of the eyeball. 
Injury to the nerve leads to paralysis of the muscle 
and double vision (diplopia) on looking downwards.

2). Lingual Nerve Damage

3). Wallenberg Syndrome

4). Trigeminal Neuralgia (Tic Douloureux/
Fother–Gill’s Disease)

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