2. It is V and Largest cranial nerve
Mixed -- Small motor root
Large sensory root
Nerve of the first pharyngeal arch
3.  Exteroceptive from
Skin of the face & forehead;
Mucous membrane of the
Floor of mouth, teeth;
Anterior 2/3 of tongue;
 Hard palate;
4. Attached to lateral part of pons
Sensory root (portio major)
Motor root (portio minor)
6.  Fibers arise from Semilunar
 Semilunar ganglion
– Develops from neural crest
– Crescent shaped
– Unipolar neurons
– Location- Meckel’s cavity;
superior to petrous part of
9.  Afferent station
 Afferent fibers accompany fibers of motor root
 Proprioception from TMJ, periodontal membrane, teeth, hard
 Afferent impulses from stretch receptors in the muscles of
12.  Located at midpontine level
 Medial to main sensory nucleus
 Fibres distribute to muscles of mastication,
mylohyoid, anterior belly of digastric, tensor
tympani, tensor veli palatini.
13.  Location – midpons
 Forms dorsal trigeminothalamic tract
 Ascending fibers terminate in this nucleus
 Convey light touch, tactile discrimination,
sense of position and passive movements
14.  True sensory ganglion
functionally ganglion cells
 Convey impulses from the muscles innervated by
the trigeminal nerve and the extraocular muscles,
as well as from the periodontal ligament of the
15.  Largest nucleus
 Extends caudally from main nucleus to level C3 of
 Forms ventral trigeminothalamic tract
 Conveys pain and temperature
16. extends to the
junction to obex
Obex(medulla) to C3
level of spinal cord
Pain and temperature
19.  Smallest division
 From anterior medial part of semilunar ganglion
lateral wall of cavernous sinus
 Sensory fibres from Scalp, skin of forehead,
upper eyelid lining frontal sinus, conjunctiva
of eyeball, lacrimal gland, skin of the lateral
angle of eyeball & lining of ethmoid cell
20. Ophthalmic division
22. LACRIMAL NERVE (n. lacrimalis)
 Smallest branch.
 Enters the orbit through the narrowest part of the superior orbital
 Runs along the upper part of the lateral rectus
 Communicates with zygomatic branch of maxillary nerve.
 Enters the lacrimal gland – gives of several filaments
 Finally pierces the orbital septum & ends in supplying the skin of
23. FRONTAL NERVE (n. frontalis)
 Largest branch.
 Enters the orbit through the superior orbital fissure.
 Runs forward between levator palpebrae superioris and
 Divides into two branches in the midway between the apex and
base of the orbit
Smaller than supratrochlear. Gives filament to join the
Supplies – Skin over the lower forehead.
Skin of the upper eyelid.
Passes through the supraorbital foramen.
Branches into medial & lateral.
Supplies – Conjunctiva.
Skin of the upper eyelid.
Twigs to pericranium.
25. Nasociliary Nerve (n. nasociliaris)
 Intermediate in size and more deeply placed.
 Enters the orbit between the two heads of rectus lateralis.
 Further passes through anterior ethmoidal foramen.
 Supplies internal nasal branches to mucous menbrane.
 Emerges as external nasal branch supplying the skin of the ala
and apex of the nose.
26.  Sensory
 From lower eyelid, side of the nose,
 All maxillary teeth & gingivae, mucous
membrane of most of nasal cavity, hard
and soft palate;
 Tonsillar region and region of pharynx
 Exits the zygomatic bone on its medial surface
 Pierces the temporal fascia to supply skin
 Receives a branch from lacrimal nerve
 Communicates with facial nerve and
 Leaves zygomatic bone on its lateral surface
 Supplies skin over malar prominence
 Communicate with facial nerve & with inferior
palpebral branch of maxillary
32. Posterior superior alveolar nerves
• Arise in the pterygopalatine fossa
• Leaves maxillary nerve in pterygopalatine
• Enters the posterior alveolar canals
 Sinus lining
 Three twigs to Molars
 Adjoining part cheek
33. Middle superior alveolar nerves
• Arise from the nerve in the posterior part of the infraorbital canal
• Runs in infraorbital groove on the lateral wall max sinus
• Supply premolars, gingiva & adjoining part cheek
• Forms a superior dental plexus with anterior and posterior superior alveolar
34. NTERIOR SUPERIOR ALVEOLAR NERVES
• Given off just before exiting from the infraorbital foramen.
• Supplies the incisor and canine teeth.
• Descends in canalis sinosus in anterior wall of maxillary sinus.
• Gives off a nasal branch to supply the mucous membrane of the anterior part
of inferior meatus and nasal floor.
• Communicates with the nasal branches of the sphenopalatine ganglion.
35. INNERVATION OF HARD PALATE
These are branches of maxillary N passing through Pterygopalatine
Lesser Palatine N ( middle & posterior ) – Uvula, tonsil, soft palate
Greater palatine nerve
Lesser palatine nerve
42. Ciliary ganglion
• Suspended from nasociliary nerve
• Anatomically belongs to trigeminal
• Functionally belongs to oculomotor
• Carries parasympathetic motor fibres
from Edinger – Westphal nucleus
43. OTIC GANGLION
• Suspended from mandibular nerve
• Anatomically belongs to trigeminal nerve but functionally
belongs to glossopharyngeal nerve
• Carries the secretomotor ( nucleus is superior salivary )fibres
& distributed via lesser superficial petrosal nerve to Parotid
44.  Suspended from lingual nerve
 Anatomically belongs to
trigeminal nerve but
functionally belongs to facial
 Carries the secretomotor
( nucleus is superior salivary )
fibres & distributed via chorda
tymoani nerve to
submandibular & sublingual
45. PTERYGOPALATINE GANGLION
• Suspended from maxillary nerve
• Anatomically belongs to trigeminal nerve but functionally
belongs to facial nerve
• Carries secretomotor fibres & distributed via the great
superficial petrosal nerve ( Nucleus is inferior salivary ) to the
Lacrimal glands & the glands of the palate
51.  Surgical removal of third molars(Von Arx and
Simpson, 1989; Rood, 1992)
 Osteotomies (Walter and Gregg, 1979; Yoshida et
 Trauma (De Man and Bax, 1988)
 Tooth extractions (Strassburg, 1967; Hansen, 1980)
 Pulpectomy (Holland, 1994)
Experimental Trigeminal Nerve Injury G.R. Holland CROBM 1996 7: 237
59.  Fracture of mandibular body and ramus
 LeFort I & II fractures
 Fracture of condylar segment medially
 Mandibular angle, body and symphysis fracture
 Inadvertent placement of screws
62.  Overinstrumentation
 Chemical injury
 Direct trauma from apicoecotomy
63.  TMJ exposures by preauricular approach
 Damage is minimized by incision and dissecting in
close apposition to cartilagenous portion of external
 Fracture of neck of condyle
64.  Trigeminal neuralgia is defined as sudden, usually
unilateral, severe, brief, stabbing, lancinating type of
pain in the distribution of one or more branches of 5th
 Specific etiology unknown
65.  Sudden, unilateral, intermittent paroxysmal, sharp,
shooting, lancinating, like pain.
 Pain is elicited by slight touching superficial ‘Trigger
 Common triggers include touch, talking, eating,
drinking, chewing, tooth brushing, etc.
66. MEDICAL TREATMENT
DRUGS CURENTLY USED:1.Carbamazepine is used as a standard drug ,
adult dose 200mg TDS & can be increased upto 1600
mg/day in divided doses
initially started as small dose & gradually increased to
prevent side effects
adverse effects include dizziness, ataxia, vertigo, skin rashes
bone marrow suppression is rare but requires routine
67. 2.Phenytoin sodium
usually used in combination of carbamazepine
side effects: gum hyperplasia
dose is 1200-3600mg/day
used with caution in patients with renal & hapatic disease
4. Gaba agonist
these drugs reduce the central projection of painful
eg. Baclofen , adult dose being 10-30 mg TDS
68. Surgical treatment
• Peripheral nerve block procedure: It involves blocking
of peripheral nerve by long acting LA.
• Alcohol block : 0.5 -2 ml of 95% alcohol can be used
for blocking of peripheral nerve.
• Blocking of gasserian ganglion: more effective but it
has hazards in sense that alcohol escape into the
surrounding subarchanoid space & may cause palsy of
adjacent cranial nerve.
69. • Post ganglionic sectioning: peripheral neurectomy in
which peripheral branch of nerve is avulsed.
• Cryotherapy: peripheral branches are subjected to
application of extreme cold by using cryoprobes
In this the nerve is not sectioned but destroyed
• Percutaneous procedure: Percutaneus procedures
involes mechanically or chemically damaging parts of
70. • Radiation therapy:
Gamma knife has been used which consists of multiple
rays of high energy photon concentrated on trigeminal
Can be used to destroy specific components of nerve
Source of radiation is Co 60
71.  Head neck and brain- bd chaurasia
 Gray’s anatomy
 Monheim’s local anesthesia and pain control in
 Handbook of local anesthesia - malamed
 Peterson’s principles of oral & maxillofacial surgery
 Experimental trigeminal nerve injury g.R. Holland
crobm 1996 7: 237