Trigeminal nerve

Trigeminal nerve Ophthalmic nerve Maxillary nerve Mandibular nerve Trigeminal ganglion Trigeminal neuralgia
Clinical applied of trigeminal nerve

1. Trigeminal nerve
Department of Oral & Maxillofacial Surgery
New Horizon Dental College & Research Institute
Presented By: Dr KaminiDadsena
Guided By:
Dr. R. S. Madan
Dr. V. Kharsan
Dr.AkshayDaga
Dr. AbhishekBalani
Dr. SumitTiwari

2. introduction:
Trigeminal nerve is largest cranial nerve, it contains both sensory and motor fiber.
It was described by Fallopius and again byMeckelin 1748. The name trigeminal was given by
Winslowon account of its three divisions.
It has 3 branches:
1.Opthalmic–sensory
2.Maxillary –sensory
3.Mandibular-mixed
General somatic afferent fibers contain both exteroceptive and proprioseptive impulses.
It attached to the lateral part of the ponsby its two roots, motor and sensory

3. ORIGIN
sensor
y
motor

4. Trigeminal nuclei
The sensory trigeminal nerve
nuclei –
largest of the cranial nerve
nuclei
extend through whole of the
brainstem.
1.The mesencephalicnucleus
-proprioception
2.The chief sensory nucleus (or
"pontinenucleus" or "main
sensory nucleus" or "primary
nucleus") –touch
3
Th i l t i i l l

6. SEMILUNAR OR
GASSERIAN GANGLION.
Sensory ganglion
corresponding to
DorsalRootGangliaof
spinal nerves.
Cresentricin shape with
convexity anterolat.
Contains cell bodies of
pseudounipolarneurons.
LOCATION: lies in a bony fossaat apex of the
petroustemporal bone
on floor of middle

THE TRIGEMINAL GANGLION

7. COVERINGS: covered by dural pouch = MECKLES CAVE OR CAVUM TRIGEMINALE.
Roof-2 layers of dura
floor-1 duraland 1endosteal durallayer.
cave lined by piaand arachnoidthus the
ganglion is bathed in CSF.
ARTERIAL SUPPLY: ganglionic branches of ICA, middle meningealartery and
accessory meningealartery.
Conti…

8. Ganglia associated with
trigeminal nerve
Associated with the three divisions of the trigeminal
nerve are four small ganglia.
The ciliaryganglionis connected with the ophthalmic
nerve.
The sphenopalatineganglionwith the maxillary nerve.
And the oticand submaxillarygangliawith the
mandibularnerve.

9. General sensations

11. SENSORY ROOT
GENERAL SOMATIC AFFERENTS
Face, Scalp, Teeth, Gingiva , Oral, Nasal cavity, PNS ,Conjuctiva, & Cornea.
Pain,temp,lighttouch touch, pressure proprioception
trigeminal gang. Bypasses trigemgang.
sensory root.
descending fibresascending fibres
FUNCTIONAL COMPONENTS

12. descending fibres ascending fibres
Spinal nuc. Principal sennuc. Mesencephalic
trigeminal leminiscus
(after crossing over and uncrossed dorsal trigeminothalamictract)
VPM nuc. Thalamus
post central gyruscerebral cortex (areas 3,2,1.)
Conti…..

13. Motor nucleus
Motor root
Mandibularnerve
muscles of mastication tensor tympani
massetor tensor palatini
lat /med pterygoids
temporalis

16. OPHTHALMIC NERVE
Smallest of the 3 branches
Purely sensory
Arises from the anteromedialend of the semilunarganglion and passes
forward in the lateral wall of cavernous sinus.
As opthalmicdivision passes forward from cavernous sinus it devidesinto
3 branches:
1.Lacrimal
2.Frontal
3.Nasociliary

17. Course:
emerges from trigeminal ganglion
lateral wall cavernous sinus
3 branches in ant part of cavernous
sinus, lacrimal, nasocilliary, frontal.
superior orbital fissure
orbit

18. Sensory or Afferent fibers from:
 Scalp
 Skin of forehead
 Conjuctiva
 Sclera
 Lacrimalgland
 Skin of the lateral angle of eyeball
 Lining of the ethmoidal cells
Upper eyelid lining the frontal sinus

19. branches
Opthalm
ic
division
Lacrimal frontal
Supraor
bital
supratro
chlear
nasociliar
y
Br in
orbit
Br in
nasal
cavity
Terminal
bron
face
Long root of
ciliaryganglion
Long ciliary
nerves
Anterior ethmoidal
Posterior ethmoidal

24. Lacrimalnerve
smallest of the three branches
Passes into orbit at the lateral angle of SOF
It runs forward on the upper border of the lateral rectus muscle It is joined by the
zygomaticotemporalbranch of the maxillary nerve, which contains the parasympathetic
secretomotorfibers to the lacrimal gland.
The lacrimalnerve then enters the lacrimalgland and gives branches to the conjunctiva and the
skin of the upper eyelid.
Occasionally it is absent, in which case it is replaced by thezygomaticotemporal nerve: the
relationship is reciprocal
Receives communicating branch from trochlearnerve

25. Frontal nerve
Largest of three branches
It enter the orbit by the way of SOF
The frontal nerve runs forward on the upper surface of
the levatorpalpebraesuperiorismuscle and divides
into the supraorbital and supratrochlearnerves
These nerves leave the orbital cavity and supply the
frontal air sinus and the skin of the forehead and the
scalp.

26. SUPRATROCHLEAR N
Smaller nerve
Medial
Receives commubranch
from infratrochlearn
Curves around sup med
margin of orbit
supplies: med
conjunctiva and UL
lower part of forehead
Lies betwnfrontalisand
corrugatorsupercilli
Larger
Lies lateral
Passes through
supraorbitalnotch
Lies beneath frontalis
Divides in med and lat
branches.
Supplies: conjunctiva,
scalp uptovertex,
mucous membrane of
frontal sinus
SUPRAORBITAL N

27. Passes through med part of sup. Orbital fissure within the tendenious
ring betwnthe two div of occulomotor nerve.
Runs along med wall of orbit betwnSO and MR
Divides into terminal branches ANT ETHMOIDAL NERVE and
INFRATROCHLEAR NERVE
branches in orbit.
NASOCILLIARY NERVE

28. 1.Sensory root of the ciliary ganglion:
the long or sensory root arises from nasociliarynerve.
2.Long cilliarynerve: 2 or 3.
run along med side of the ON
pierce sclera and supply cornea, iris, cilliarybody.
carry pain temp and touch.
sympathetic motor supply to dilator pupillae.
3.Posterior ethmoidalbranch:
passes thru post ethmoidalforamen to supply the ethmoidand sphenoid PNS.
conti

29. 4.InfratrochlearNerve
smaller terminal branch
emerges below trochlea
appears on face above med angle the eye.
supplies: upper half of external nose
skin of med most part of UL andLL
medial conjunctiva
lacrimalsac
caruncle

30. 5. Anterior ethmoidalnerve:
largarterminal branch
course:
ant ethmoidalforamen and canal
into ant cranial fossaon sup surf of cribriformplate
Through slit lat to cristagalliinto nasal cavity
Med internal nasal branch lat internal nasal branch
Supplies ant nasal septum supplies ant part lat nasal
cavity emerges as
external nasal nerve to
skin of ala,vestibule,and
tip of nose

32. Corneal Reflexes:

33. Tearing reflex:

34. CLINICAL APPLICATION OF TRIGEMINAL
GANGLION
Shingles and varicella-zoster: The trigeminal
ganglion, as any sensory ganglion, may be the
site of infection by the herpes zoster virus
causing shingles, a painful vesicular eruption in
the sensory distribution of the nerve.
Trigeminal neuralgia (tic douloureux): This is
severe pain in the distribution of the trigeminal
nerve or one of its branches, the cause often
being unknown. It may require partial
destruction of the ganglion.
34

35. CLINICAL APPLICATION
Ethmoid tumours
Malignant tumoursof the mucous lining of the
ethmoidair cells may expand into the orbits,
damaging branches of opthalmic nerve. This may
lead to displacement of the orbital contents
causing proptosisand squint, and sensory loss over
the anterior nasal skin.
Nasal fractures
Trauma to the nose may damage the nasociliary
nerve. Sensory loss of the skin down to the tip of the
nose may result.
35

36. Corneal reflex: When the cornea is touched, usually with a wisp of
cotton, the subject blinks. This tests V and VII. The nerve impulses pass
through cornea and then through nasociliary nerve to the brain.
Supraorbitalinjuries
Trauma to the supraorbitalmargin may damage the supraorbital
and supratrochlearnerves causing sensory loss in the scalp.
36

37. CORNEAL REFLEX
Ask the patient to look upward
to the ceiling and gently
depress the lower eyelid
Lightly touch the lateral edge
of the cornea with damp cotton wool
Look for both direct and
consensual blinking

38. Maxillary nerve

39. MAXILLARY NERVE
Second division of trigeminal nerve
Pure sensory
Supplies derivatives of maxillary process and frontonasalprocess.

40. i
Course: trigeminal gang. Middle cranial fossa
lat wall of cavernous sinus
foramen rotundum
pterigopalatinefossa
in groove on post surf of maxilla
through inforbital fissure into orbit as INFRA ORBITAL N
through infraorbitalforamen on face

41. COURSE

42. Innervations:
1.Skin:
•Middle portion of face
•Lower eyelid
•Side of nose
•Upper lip
2.Mucous membrane:
•Nasopharynx
•Maxillary sinus
•Soft palate
•Hard palate
•Tonsil
3.Maxillary teeth and pdl

43. MAXILLARY NERVE
Within craniumIn pterygopalatine fossa In infraorbitalcanal On face
Middle
meningeal
nerve
Inferior palpebral
Lateral nasal
Superior labial
MSA (middle superior alveolar nerve)
ASA
(anterior
superior
alveolar nerve)
Zygomatic
PSA (posterio
rsuperior alveolar)
Pterygopalatin e
Zygomaticotemporal
Zygomatic
o
facial
Orbital Nasal Palatine Pharynge al
Ganglionic
branch

44. WITHIN CRANIUM
Middle meningealnerve
It leaves the maxillary nerve near the foramen rotundum.
It runs along with the middle menigealartery to supply the
duramaterin the middle cranial fossa

45. IN PTERYGOPALATINE FOSSA
1.Ganglionicbranches-
related to pterigopalatine ganglion
Carry sensations from orbital periosteum , nose, pharynx,palate
Carry post ganglionicparasymp. Secretomotorfibresto lacrimal
gland

46. ZygomaticNerve:
Starts in the pterygopalatinefossa
Enters the orbit through the infraorbitalfissure along its
lateral border where it divides into 2 branches :
Zygomatictemporal
Zygomaticfacial

47. A. zygomaticofacialnerve
Appears on face through
foramen in the zygomatic bone
Supplies skin on prominence of
cheek
B. zygomaticotemporalnerve
Supplies skin of temporal
region after peircing temporal
fascia 2 cm above zygoma
Gives communicating branch to
lacrimalN

49. Posterior superior alveolar
nerve:
•It supply Maxillary molars & their gingivae
•Pass through the apical foramen of the roots of the molars except the
mesiobuccalroot of the first molar.
•Mucous membrane of the maxillary sinus

51. 2. PTERYGOPALATINE NERVE
These are communications between
pterygopalatine ganglion & maxillary nerve

52. orbital branch
Supply the periosteumof orbit.

53. NASAL BRANCH
Supplies –
mucous membrane of superior & middle conchae
lining of posterior ethmoidalsinus
posterior part of nasal septum

54. NASOPALATINE BRANCH

55. PALATINE BRANCH
GREATER PALATINE /
ANTERIOR PALATINE
BRANCH
LESSER PALATINE
(MIDDLE & POSTERIOR
PALATINE)

56. PHARYNGEAL BRANCH
Leaves the posterior part of
pterygopalatine ganglion
pharyngeal canal
Supplies the mucous membrane of
nasopharynx&
posterior part of eustachiantube.

57. In infraorbitalcanal

58. Superior alveolar branches
Middle superior alveolar : maxillary bicuspids
Anterior superior alveolar : maxillary cental, lateral incisors & cuspids

59. Middle superior alveolar br: form the superior dental plexus
of nerves within the maxillary sinus
: as a direct branch of infraorbital n.
the middle superior alveolar n. may be missing and that the maxillary
bicuspids receive their sensory innervationfrom the
superior dental plexus.
.

60. Terminal branches
The palpebral branchascend deep to the orbicularis
oculi, piercing the muscle to supply the skin in the
lower eyelid.
The nasal branchessupplies the skin of the side of
the nose and of the movable part of the nasal septum.
Superior labial branchsupply the skin of anterior
part of cheek, upper lip, oral mucosa and labial
glands.

61. Applied anatomy:
Causes of injury to Maxillary nerve –
1.Maxillofacial surgical procedures
Orthognathicsurgeries
head & neck preprostheticsurgeries
Treatment of benign & malignentlesions
2.Trauma & facial fractures
3.Dental implant placement
4.Endodontic therapy
5.Tratmentof pathology (specially periapical)
6.During administration of local anesthesia

62. Cavernous sinus thrombosis
-Cavernous sinus
syndrome is a medical
emergency, requiring
prompt medical
attention, diagnosis, and
treatment
-Result from involvement
of CS by
inflammatory/septic foci.

63. Potential causes of cavernous
sinus syndrome include –
1.metastatic tumors,
2.direct extension of nasopharyngeal
tumors,
3.meningioma,
4.pituitary tumors,
5.aneurysms of the intracavernous
carotid artery
6.bacterial infection causing
cavernous sinus thrombosis,
7.aseptic thrombosis,
8.fungal infections.

64. Clinical features:
•High grade fever
•Altered consciousness
•Severe infection in danger area of face
•Chemosis
•Proptosis
•Opthalmoplagia
multiple cranial neuropathies.
-exophthalmos
-sensory loss in V1 and / or V2.

65. Treatment:
early and aggressive Broad spectrum parentral
antibiotic administration for 3- 4 weeks.
IV mannitoltoreduceintracrainialpressure.
Anticoagulant to prevent ext. of thrombosis. Heparin
20,000 unit in 1500 ml of D5 or 200mg dicumarolorally
followed by 100mg daily.
Corticosteroid reduced intra cranial tension but there
is risk of spread of infection.
Neurosurgical intervention is mandatory.

66. Trauma to bones of skull & face
malarfractures-Trauma to infraorbitalmargin may
cause sensory loss of infraorbital skin.

67. Caldwell-Luc Approach:

68. Posterior superior alveolar
block:

69. Making NasopalatineBlocks Comfortable: A RandomisedProspective
Clinical Comparison of Pain Associated with the Injection Using an Insulin
Syringe and a Standard Disposable 3mLSyringe
SundararamanPrabhu,SyedFaizel,VedantPahlajani,andShwetaJha
Prabhu
J MaxillofacOral Surg.2013 December;12(4): 436–439.

70. Making NasopalatineBlocks Comfortable: A Randomised
Prospective Clinical Comparison of Pain Associated with the Injection
Using an Insulin Syringe and a Standard Disposable 3mLSyringe
J MaxillofacOral Surg.2013 December;12(4): 436– 439.
Published online 2012 August 1.doi:
10.1007/s12663- 012-0412- 4
PMCID:PMC3847027
Making NasopalatineBlocks Comfortable: A RandomisedProspective Clinical Comparison of Pain
Associated with the Injection Using an Insulin Syringe and a Standard Disposable 3mLSyringe
SundararamanPrabhu,SyedFaizel,VedantPahlajani,andShwetaJhaPrabhu
Aim:
This study was conducted to compare and evaluate the pain associated with
administration of Nasopalatineblocks usinga disposable insulin syringeand
theconventional disposable3 mLsyringe.
ConclusionPain associated with administration of the nasopalatine blocks may be
significantly mitigated by using the Insulin syringe

71. MAXILLARY SINUS
INFECTIONS
Infections of the maxillary sinus may cause
infraorbitalpain or may cause referred pain
to other structures supplied by Vb(e.g.
upper teeth).

72. Wallenberg syndrome :
vertebral artery occlusion
infarction of lateral medulla
symptoms –
ipsilateralfacial sensory loss,
ipsilateralhorners,
ipsilateralIX,X,XI palsy
contralateralsensory loss

73. Gradenigo’ssyndrome:
first described in 1904 by GuiseppeGradenigo.
It is defined as a clinical triad of otitis media, severe pain originating from
the trigeminal nerve, and ipsilateral sixth cranial nerve palsy.
J Med Case Rep.2014;8: 217.
Published online 2014 June 23.doi:10.1186/1752-1947- 8-217
PMCID:PMC4086707
Gradenigo’ssyndrome secondary to chronic otitismedia on a
background of previous radical mastoidectomy : a case report
YuvatiyaPlodpai,
1
SiripornHirunpat,
2
andWeerawatKiddee
3
Author information►Article notes►Copyright and License
information►

74. PterygopalatineGanglion:
Sphenopalatineganglion is the largest
parasympathetic ganglion, suspended by two roots of
maxillary nerve.
Functionalyit is related to facial nerve.
It is also the ganglion of hay fever.
Roots:
Sensory, sympathetic and secreatomotoror
parasympathetic roots.

75. Sensory roots is from maxillary nerve
Sympathetic roots is from postganglionic plexus
around ICA. The nerve is called deep petrosal. It unites
with greater petrosal to form the nerve of pterygoid
canal. The fibresof deep petrosalnerve do not relay
on ganglion.

79. Clinical examination of
maxillary nerve:
Sensory: apply gentle touch, pinpricks, or warm or cold
objects to areas supplied by the nerve and note
responses;
Reflex: sneeze reflex.

80. Sneeze Reflex:

81. Mandibular nerve
Department of Oral & Maxillofacial Surgery
New Horizon Dental College & Research Institute
Presented By: Dr. KaminiDadsena

82. Outline:
Introduction
Innervation
Branches there courses & innervation:
1.Undivided nerve
2.Ant. Division
3.Post. Division
Clinical applied part:
1.Mandibular Nerve block
2.Lingual nerve injury
3.Frey syndrome

83. 4.Trigeminal neuralgia
5.Inferior alveolar canal & impacted mand. 3
rd
molar
6.Bifid mandibularcanal
7.Mandibular orthognathicsurgery complication
8.Traumatic neuroma
9.Trotter syndrome
Clinical examination of fifth nerve
Ganglia- otic& submandibular
Conclusion

84. Introduction:
Mandibular nerve is the largest branch of the
trigeminal nerve.
Mixed nerve with two roots:
1.Large sensory : from inferior angle of TGG
2.Small motor : Motor cells located in pons & medulla

85. Origin:
sensor
ymotor

86. Course:

88. Innervations:
1.Sensory roots:
a)Skin:
Temporal region
Auricula
Ext. auditory meatus
Cheek
Lower lip
Lower part of face
b.Mucous membrane
Cheek
Tongue
Mastoid cells
c.Mandibular
teeth and pdl
d.Bone of
mandible
e.TMJ
f.Parotid gland

89. 2.Motor roots
a.Masticatory muscles:
Masseter
Temporalis
Medial pterygoid
Lateral pterygoid
b.Mylohoid
c.Ant. Belly of digastric
d.Tensor tympani
e.Tensor velipalatini

90. Branches of Mandibular Nerve
Mandibular
nerve
Branches from
undivided nerve
Nervusspinosus
Nerve to medial
pterygoid
Nerve to tensor
tympani
Nerve to tensor
veli palatini
Branches from
anterior division
Nerve to lateral
pterygoid
Nerve to
massetermuscle
Nerve to
temporal muscle
Buccalnerve
Branches from
posterior division
Auriculotemporal
nerve
Lingual nerve
Inferior alveolar
nerve
Incisive nerve
Mental nerve
Mylohyoidnerve

91. Branches from undivided nerve:

92. Nervusspinosus:
Reenter the crainium through foramen spinosumalong
with middle meningealart..
Supply:
1.Duramater
2.Mastoid air cells

93. Meningeal
branch
with
middle
meningeal
artery

94. Nerve to medial pterygoid:
Motor nerve to medial pterygoid
It gives small branches to tensor velipalatiniand
tensor tympani.

96. Branches from anterior division:

97. Branches from anterior
division:
Smaller than post. Division.
Runs forward under lateral pterygoid .

98. Buccalnerve:
Also k/a buccinator or long
buccalnerve.
Passes between two heads of
lateral pterygoidmuscle.
Sensory fibresto
1.Skin of cheeks
2.Buccalgingivato
mandibularmolars
3.Mucobuccalfold

100. Massetricnerve, deep temporal
nerves & nerve to lat. Pterygoid:

101. Branches of the posterior division:

102. Auriculotemporalnerve:
Arises by a medial & lateral root.
Communications:
Each root receives communicating fibers from the otic
ganglion;
which are sensory & secretomotor to parotid gland.

103. Auriculotemporal
nerve
Inferior alveolar nerve
Mylohyoidnerve
Lingual nerve

104. Branches :
Communication to facial:
Oticgang.: sensory, secretoryand
vasomotor to parotid
Articular: posterior part of TMJ
Ant. Auricular : skin over the helix & tragus of
ear
Ext. auditory Meatal: skin lining the meatus
& tympanic membrane
Superficial temporal branch : skin over the
temporal region

105. Lingual nerve
Passes downward medial to lat. Pterygoid
In pterygopalatinespace, between ramusand medial
pterygoid
Runs parallel to inf. Alveolar nerve
Lies below and behind lower 3
rd
molar.
Proceeds ant. In muscle of tongue

106. Sensory:
1.To ant. 2/3
rd
of tongue
2.Floor of mouth
3.Gingivato lingual surface
of mandible

107. Inferior alveolar nerve:
Largest br. Of post. Division.
Lies medial to lateral pterygoid
Enter mandibularcanal.
Throughout the path it accompany with IAA & IAV.

108. Mylohyoidnerve
Br. From IAN before it enter in mandibularcanal.
Runs downward & forward in mylohyidgroove
It is mixed nerve.
Supply:
1.Motor to mylohyid muscle & ABD
2.Sensory to skin on the ant & inf. Surface of mental
protuberance
3.Sensory innervationto mandi. Incisors and mesial
roots of mandibular1
st
molar.

109. Terminal branches
IAN divided into mental and insivenerve.
Incisive nerve remains in mand. Canal and supply
mandi. 1
st
PM, C & I.
Mental nerve: exit the canal through mental foram.
And divided into 3 branches to that innervate the skin
of the chin, skin & mucous membrane of lower lip.

110. Clinical applied part:

111. Nerve block:
Complication of Inferior alveolar nerve block:
1.Failure of anesthesia: due to accesorysensory
innervationto mandibularteeth esp. mylohyoid
nerve.
2.Hematoma:
3.trismus
4.Transient facial paralysis

112. Complication of mandibularnerve block:
1.Gow–gate tech.:
 hematoma
Trismus
temporary paralysis of 3
rd
, 4
th
, & 6
th
nerve complete paralysis of eye
for 20 min.
1.Vazirani-akinosiclosed mouth tech:
 failure to anesthesia
Hematoma
Trismus
Transient facial paralysis

113. Mental nerve block complication:
Hematoma
Paresthesiato lip &/or chin
Complication of Incisive nerve block:
Failure of anesthesia:
Hematoma
Paresthesiato lip&/or chin

114. Lingual nerve injury
Surgical trauma:
1.Complication of the regional blocking of nerve
2.Extraction of the mandibular3
rd
molars
3.Jaw fracture
4.Stone in the submandibulargland duct
5.Probing or removing such stones
6.Accidental laceration of the ventral surface of
tongue during dental restoration
7.Rarely TUMOUR in this region
EFFECTS: various sensation of pain, numbness,
burning, altered gustatory function

116. Frey syndrome:
1
st
described by frey.
It is localisedgustatory sweating in the area supplied by
auriculotemporalnerve.
Cause:
Congenital or acquired
Surgery of parotid gland, TMJ , parotid abscess, facial wound.
Clinical feature:
1.Pain in area supplied by ATN
2.Gustatory sweating
3.Erythema& flushing
4.Positive iodine starch test

118. Treatment:
1.Antiperspirants
2.Anticholinergicprepn: glycopyrolate
3.Botulinumtoxin A inj.
4.Radiation therapy: 50 Gy
5.Surgical:
i.Skin excision: for localise & small area
ii.ATN section: not permanent
iii.Tympanic neurectomy: safe procedure

119. Trigeminal neuralgia:
Tic douloureux; Trifacialneuralgia;
Fothergill’s disease
Definition: paroxymalepisode of sudden, usually
unilateral, severe recurrent pain of shearing, stabbing
or lancinatingtype in distribution of one or more
branches of 5
th
cranial nerve, accompanied by
spasmodic contraction of facial muscles, often
initiated by ‘trigger zone’.
British journal of anesthesia(2001)

120. Etiology of TN:
Mostly idiopathic
Peripheral cause:
1.Nerve compression, trauma,
2.Herpes zoster infection
3.Aneurysm around nerve
4.Demyelinationaround the nerve
Central cause:
1.Microaneurysmaround nerve
2.Cerebropontineangle tumors
3.Multiple sclerosis
4.Demyelinationof the nerve
5.Pulsation of basillarartery
6.High petrousridge

121. Clinical feature:

122. Trigger points
•vermillion border of the
lips, alaeof nose, the
cheeks, teeth & gums of
lower jaw & around the
eyes.
•Eating, chewing, washing
face, shaving, smiling,
speaking, brushing,
applying make- up,
encountingsoft breeze.

123. •In the early stages pain is mild; of short duration with the
refractory period between the attacks; but at later stage the
pain becomes severe & tend to occur at more frequent
intervals.

124. Treatment:
MEDICAL
Anti-convulsants: Carbamazepine( initial dose 200 mg three times a day &
tritatedover 1 to 5 weeks period; eventually increasing to 800- 1200 mg)
Phenytoin
Baclofen( GABA inhibitor )
Sodium Valproate( 600 mg ) Clonazepam( 1.5 mg/day )
Newer Anti-convulsants: Gabapentin, Lamotrigine, Vigabatrin
Corticosteroids
Tricyclicanti-depressants: Amitryptyline

125. SURGICAL:
Extracranial: Alcohol block in peripheral n.
Nerve section & avulsion
Electrosurgery
Cryosurgery
Selective radio frequency thermocoagulation
Peripheral neurectomy: Supraoribtal
Infraorbital
Lingual
Inferior alveolar

126. Intracranial: Alcohol blockade at gasserianganglion
RFTC at gasserian ganglion
Retrogasserianrhizotomy
Medullarytractotomy
Midbrain tractotomy
Intracranial nerve decompression
Microvasculardecompression (MVD)

128. •Newer approaches:
a) Physiologic inhibition of pain by transcutaneousneural stimulation
b) Acupuncture
•Psychologicapproaches :
a) Biofeedback
b)Psychiatric counseling
c) Hypnosis

129. IAN injury
 Third molar surgery-
1 Upto25% pts may not exp. spontaneous recovery of
sensation within one year.
2 Greater than 1 yr> microsurgery to be performed.
3.Mesioangularimpactions greatest risk for nerve
damage followed by horizontal.
4.0.33% reported cases of paresthesia& 0.184% with
permanent damage
# 2005 OOOE –RADIOGRAPHIC PROXIMITY OF MAND THIRD MOLAR TO INF. ALV N.

130. Rood & Sehab1990
A. Radiolucencyacross
the roots
B. Deviation of mandibular
canal
C. Interruption of canal
D. Deflection of third molar
root by the canal
E. Narrowing of third molar
root

131. Orthognathicsurgery
1.BSSO highest incidencceof neurosensorydisturbances.
2.Injuries most common at mandibularforamen during osteotomies.
3. Mand . advancement result in stretch injury & application of rigid fixation
cause mechanical & compression type of injury
4. As IAN appr. mental foramen increase risk during implant placement or
genioplasty

132. Bifid mandibularcanal

133. Dental implants
1.It is suspect to post. Region of
mandible & ant. To mental
foramen
2.Placement of endosseus
implants result in 100% transient
hypoesthesia & 16% permanent
sensory loss

134. Preauricularsurgical approaches to
the mandible condyleor neck will
routinely expose the terminal
auriculotemporaln. trunk along with
superficial temporal artery.
Trauma
Nerve impingement sec. to fracture
displacement

135. Traumatic Neuroma
Benign tumor
Exuberant attempt at repair of the damaged nerve
trunk
Following accidental or purposeful sectioning of a
nerve , difficult extraction
Oral traumatic neuroma: small nodule or swelling of
the mucosa typically near mental foramen, on the
alveolar ridge in edentulous areas or on the lips or
tongue.
Treatment: surgical excision of the nodule.

136. Trotter syndrome:
In nasopharyngealcarcinoma, thetumormay extend
laterally and involve thesinus of Morgagni sinus
involving themandibularnerve.
This produces a triad of symptoms known asTrotter's
Triad. These symptoms are:
1) Conductive deafness (due toeustachian
tubeinvolvement)
2)Ipsilateralimmobility of thesoft palate
3)Trigeminal neuralgia

137. Ganglia associated by mandi.
nerve

138. Submandibularganglia:
Sensory roots from lingual nerve. And it suspended by
two roots of lingual nerve.
sympathetic plexus is from the sympathetic flexus
around the facial artery. This plexus contains post
ganglionicfibresfrom superior cervical ganglion of
sympathetic trunk. These fibre vasomotor to the gland.
Secreatomotorroots is from superior salivatorynucleus
through nervusintermediusvia chordatympani. CT
joins lingual nerve. Parasympathetic fibreget relayed
in submandibularganglion.

139. related to lingual nerve,
rests on hyoglossusmuscle
supplies post ganglionic Parasympethetic
secretomotorfibresto submandibularand sublingual
gland.

141. Br. To the Submandibulargland and sublingual
gland

142. Oticganglion:
The oticganglion lies deep to the trunk of mandibular
nerve, between nerve and tensor velipalatinimuscle
in infra temporal fossa , just distal to foramen ovale.
Topographicalyit is related to mandibular nerve bt
functionalyit is related to glossopharyngealnerve.
Roots:
1.Sensory roots from auriculotemporalnerve.

143. 2.Sympathetic roots from plexus around middle
meningealartery.
3.Secretomotorroots is by lesser petrosal nerve from
the tympanic plexus formed by tympanic branch of
glossopharyngealnerve. Fibresof lesser petrosal
nerve relay in otic ganglion. Postganglionic fibres
reaches the gland through auriculotemporalnerve.

144. Cont….
Branches:
1.Post ganglionicbranches of ganglion pass through
auriculotemporalnerve to supply parotid gland
2.Motor branches to supplytwo muscle tensor
tympani and tensor velipalatini.

145. 4. OTIC GANGLION:
between trunk of mandibular nerve and tensor palatini

147. Clinical examination of nerve
Sensory: apply gentle touch, pinpricks, or
warm or cold objects to areas supplied by
the nerve and note responses.
Jaw jerk reflex:
Afferent-sensory portion of trigeminal n.
Reflex centre –pons
Significance-
1.Normal response slight
2.Brisk in supranuclearlesions of pyramidal
tracts above the nucleus of trigeminal n.

148. Reflex:

149. Ganglia associated
with trigeminal nerve

150. Ganglion:
Ganglia are aggregations of neuronal somataand are of varying form
and size.
They occur in
1.the dorsal roots of spinal nerves
2.Sensory roots of cranial nerves ietrigeminal, facial, glossopharyngeal ,
vagaland vestibulocochlear
3.autonomic nerves
4.enteric nervous system.
Each ganglion is enclosed within a capsule of fibrous connective tissue
and contains neuronal somata and neuronal processes
Some ganglia, particularly in the ANS, contain fibresfrom cell bodies that
lie elsewhere in the nervous system and that either pass through, or
terminate within, the ganglia.

151. SubmandibularGanglia
The submandibularganglia lies superficial to
hyoglossusmuscle in submandibularregion.
Functionally submandibularganglion is connected to
facial nerve, while topologically it is connected to
lingual nerve.
Roots:
It has sensory, sympathetic and secreatomotor or
parasympathetic roots.

152. Sensory roots from lingual nerve. And it suspended by two roots of
lingual nerve.
sympathetic plexus is from the sympathetic flexus around the facial
artery. This plexus contains post ganglionicfibresfrom superior
cervical ganglion of sympathetic trunk. These fibrevasomotor to the
gland.
Secreatomotorroots is from superior salivatorynucleus through nervus
intermediusvia chordatympani. CT joins lingual nerve.
Parasympathetic fibreget relayed in submandibular ganglion.

153. related to lingual nerve,
rests on hyoglossus
muscle
supplies post ganglionic
Parasympethetic
secretomotorfibresto
submandibularand
sublingual gland.
SUBMANDIBULAR GANGLION

154. Br. To the Submandibulargland and sublingual
gland

155. PterygopalatineGanglion:
Sphenopalatineganglion is the largest
parasympathetic ganglion, suspended by two roots of
maxillary nerve.
Functionalyit is related to facial nerve.
It is also the ganglion of hay fever.
Roots:
Sensory, sympathetic and secreatomotoror
parasympathetic roots.

156. Sensory roots is from maxillary nerve
Sympathetic roots is from postganglionic plexus
around ICA. The nerve is called deep petrosal. It unites
with greater petrosal to form the nerve of pterygoid
canal. The fibresof deep petrosalnerve do not relay
on ga

159. Cilliaryganglion:
Very small gangliompresent in orbit.
Topographically, it is related to nasociliarynerve but
functionalyit is related to occulomotor nerve .
Roots:
1.Sensory from long ciliarynerve
2.Sympathetic roots from long ciliarynerve from
plexus around opthalmic artery.
3.Parasympathetic root is from a branch to inferior
oblique muscle.

160. Cont……
Parasymph. Fibresarises from Edinger-westphal
nucleus, join occulomotor nerve and leave it via nerve
to IO
Branches:
1.Gang.gives10-12 short ciliarynerve containing post
ganglionicfibresfor the supply of constrictor or
sphinctorpupillaefor narrowing the size of pupil
and ciliarymuscles for increasing curvature of ant.
Surface of lens during accomodationof eye.

163. Oticganglion:
The oticganglion lies deep to the trunk of mandibular
nerve, between nerve and tensor velipalatinimuscle
in infra temporal fossa , just distal to foramen ovale.
Topographicalyit is related to mandibular nerve bt
functionalyit is related to glossopharyngealnerve.
Roots:
1.Sensory roots from auriculotemporalnerve.

164. 2.Sympathetic roots from plexus around middle
meningealartery.
3.Secretomotorroots is by lesser petrosal nerve from
the tympanic plexus formed by tympanic branch of
glossopharyngealnerve. Fibresof lesser petrosal
nerve relay in otic ganglion. Postganglionic fibres
reaches the gland through auriculotemporalnerve.
4.Motor root is by branch from nerve to medial
pterygoid. This branches underlying through the
ganglion and devidedinto two branches to supply
tensor tympani and tensor velipalatini

165. Cont….
Branches:
1.Post ganglionicbranches of ganglion pass through
auriculotemporalnerve to supply parotid gland
2.Motor branches to supplytwo muscle tensor
tympani and tensor velipalatini.

166. 4. OTIC GANGLION:
between trunk of mandibular nerve and tensor palatini
supplies post ganglionic
Parasympetheticsecretomotor
fibresto parotid gland.

168. Conclusion:
Mandibular nerve is one of the imp. Nerve of head &
neck.
It is nerve of 1
st
brachial arch.
Most commonly invovedin TN
Lingual nerve is most commonly involve in minor
surgical procedure of 3
rd
molar area
Injury to lingual, mental & IAN can be avoided by
proper tech.
Auriculotemporalnerve injury can be prevented by
modification of incision line.