2. It is V and Largest cranial nerve
Mixed -- Small motor root
Large sensory root
Nerve of the first pharyngeal arch
2
3. Exteroceptive from
Skin of the face & forehead;
Mucous membrane of the
nasal cavity;
Oral cavity;
Nasal sinus;
Floor of mouth, teeth;
Anterior 2/3 of tongue;
Cranial dura
Proprioception
from
Teeth;
Periodontium;
Hard palate;
TMJ
3
4. Attached to lateral part of pons
Sensory root (portio major)
Motor root (portio minor)
4
6. Fibers arise from Semilunar
Ganglion
Semilunar ganglion
– Develops from neural crest
– Crescent shaped
– Unipolar neurons
– Location- Meckel’s cavity;
superior to petrous part of
temporal bone
6
9. Afferent station
Afferent fibers accompany fibers of motor root
Proprioception from TMJ, periodontal membrane, teeth, hard
palate
Afferent impulses from stretch receptors in the muscles of
mastication
9
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.
12
13. Location – midpons
Forms dorsal trigeminothalamic tract
Ascending fibers terminate in this nucleus
Convey light touch, tactile discrimination,
sense of position and passive movements
13
14. True sensory ganglion
Contains
cells
that
are
structurally
and
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
teeth
14
15. Largest nucleus
Extends caudally from main nucleus to level C3 of
spinal cord
Forms ventral trigeminothalamic tract
Conveys pain and temperature
15
16. extends to the
pontomedullary
junction inferiorly
pontomedullary
junction to obex
Tactile sense
Obex(medulla) to C3
level of spinal cord
Pain and temperature
16
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
19
22. LACRIMAL NERVE (n. lacrimalis)
Smallest branch.
Enters the orbit through the narrowest part of the superior orbital
fissure
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
upper eyelid.
22
23. FRONTAL NERVE (n. frontalis)
Largest branch.
Enters the orbit through the superior orbital fissure.
Runs forward between levator palpebrae superioris and
periosteum
Divides into two branches in the midway between the apex and
base of the orbit
Supratrochlear
Supraorbital
23
24. •
Supraorbital
Smaller than supratrochlear. Gives filament to join the
infratrochlear.
Supplies – Skin over the lower forehead.
Conjunctiva
Skin of the upper eyelid.
Supratrochlear
Passes through the supraorbital foramen.
Branches into medial & lateral.
Supplies – Conjunctiva.
Skin of the upper eyelid.
Twigs to pericranium.
24
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.
25
26. Sensory
From lower eyelid, side of the nose,
upper lip;
All maxillary teeth & gingivae, mucous
membrane of most of nasal cavity, hard
and soft palate;
Tonsillar region and region of pharynx
26
31. Zygomaticotemporal:
Exits the zygomatic bone on its medial surface
Pierces the temporal fascia to supply skin
over temple
Receives a branch from lacrimal nerve
Communicates with facial nerve and
auriculotemporal branch
Zygomaticofacial
:
Leaves zygomatic bone on its lateral surface
Supplies skin over malar prominence
Communicate with facial nerve & with inferior
palpebral branch of maxillary
31
32. Posterior superior alveolar nerves
• Arise in the pterygopalatine fossa
• Leaves maxillary nerve in pterygopalatine
fossa
• Enters the posterior alveolar canals
Branches to
Sinus lining
Three twigs to Molars
Gingiva
Adjoining part cheek
32
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
branches
33
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.
34
35. INNERVATION OF HARD PALATE
Sensory innervations
Greater palatine
Nasopalatine
These are branches of maxillary N passing through Pterygopalatine
ganglion
Lesser Palatine N ( middle & posterior ) – Uvula, tonsil, soft palate
Pterygopalatine ganglion
Greater palatine nerve
Lesser palatine nerve
35
42. Ciliary ganglion
• Suspended from nasociliary nerve
• Anatomically belongs to trigeminal
nerve
• Functionally belongs to oculomotor
nerve
• Carries parasympathetic motor fibres
from Edinger – Westphal nucleus
42
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
glands.
43
44. Suspended from lingual nerve
Anatomically belongs to
trigeminal nerve but
functionally belongs to facial
nerve
Carries the secretomotor
( nucleus is superior salivary )
fibres & distributed via chorda
tymoani nerve to
submandibular & sublingual
salivary glands.
44
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
45
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
59
63. TMJ exposures by preauricular approach
Damage is minimized by incision and dissecting in
close apposition to cartilagenous portion of external
auditory meatus
Fracture of neck of condyle
63
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
cranial nerve
Specific etiology unknown
64
65. Sudden, unilateral, intermittent paroxysmal, sharp,
shooting, lancinating, like pain.
Pain is elicited by slight touching superficial ‘Trigger
points’
Common triggers include touch, talking, eating,
drinking, chewing, tooth brushing, etc.
65
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
.
,etc
bone marrow suppression is rare but requires routine
.
monitoring
66
67. 2.Phenytoin sodium
usually used in combination of carbamazepine
dose 100-400mg/day
side effects: gum hyperplasia
3. Gabapentin
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
impulses
eg. Baclofen , adult dose being 10-30 mg TDS
67
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.
68
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
trigeminal groove
69
70. • Radiation therapy:
Gamma knife has been used which consists of multiple
rays of high energy photon concentrated on trigeminal
nerve root.
Can be used to destroy specific components of nerve
Source of radiation is Co 60
70
71. Head neck and brain- bd chaurasia
Gray’s anatomy
Monheim’s local anesthesia and pain control in
dental practice
Handbook of local anesthesia - malamed
Peterson’s principles of oral & maxillofacial surgery
Experimental trigeminal nerve injury g.R. Holland
crobm 1996 7: 237
71