The trigeminal nerve is the 5th cranial nerve that has both sensory and motor components. It has three divisions - the ophthalmic, maxillary, and mandibular divisions. The ophthalmic division supplies sensory innervation to the face above the eyes. The maxillary division supplies sensory innervation to the midface. The mandibular division is the largest division and supplies motor innervation to the muscles of mastication as well as sensory innervation to the lower face and oral cavity. The trigeminal nerve is important clinically as lesions or damage can result in sensory deficits, pain syndromes like trigeminal neuralgia, or paralysis of the muscles of mastication.

1. TRIGEMINAL NERVE
JOYAL JOICE
2012 BATCH

2. CONTENTS
• INTRODUCTION
• ORGIN OF TRIGEMINAL NERVE
• NUCLEI OF TRIGEMINAL NERVE
• MOTOR ROOT OF TRIGEMINAL NERVE
• SENSORY ROOT OF TRIGEMINAL NERVE AND ITS
BRANCHES
• CLINICAL ANATOMY
• REFERENCES

3. INTRODUCTION
• TRIGEMINAL NERVE IS THE FIFTH CRANIAL NERVE
• IT IS THE LARGEST CRANIAL NERVE
• CONTAINS BOTH SENSORY AND MOTOR
COMPONENTS
• MOTOR ROOT SUPPLIES THE MUSCLES OF
MASTICATION AND OTHER MUSCLES IN THE REGION
• SENSORY PART SUPPLIES THE SKIN OVER THE
ENTIRE FACE AND MUCOUS MEMBRANE OF THE
CRANIAL VISCERA AND ORAL CAVITY EXCEPT FOR
THE PHARYNX AND BASE OF TONGUE
• IT IS ATTACHED TO THE LATERAL PART OF THE
PONS BY ITS TWO ROOTS,MOTOR AND SENSORY

4. ORGIN OF TRIGEMINAL NERVE
ORGINATED FROM THE LATERAL BORDER OF PONS

5. NUCLEI OF TRIGEMINAL NERVE
1.THE MESENCEPHALIC NUCLEUS
2.THE CHEIF SENSORY NUCLEUS
3.THE SPINAL TERMINAL NUCLEUS

7. MOTOR ROOT
• THE MOTOR ROOT ARISES FROM THE MOTOR
NUCLEUS WITHIN THE PONS AND MEDULLA.FIBRES
RUN ANTERIORLY ALONG WITH,BUT SEPARATE
FROM,THE LARGER SENSORY ROOT OF THE
TRIGEMINAL GANGLION.IT RUNS LATERALLY AND
INFERIORLY TOWARDS THE FORAMEN OVALE.IT
THEN UNITE WITH THE SENSORY ROOT OF THE
MANDIBULAR DIVISION.

8. • MOTOR FIBRES OF TRIGEMINAL NERVE SUPPY THE
FOLLOWING MUSCLES
1.MUSCLES OF MASTICATION
• MASSETER
• TEMPORALIS
• MEDIAL PTERIGOID
• LATERAL PTERIGOID
2.MYLOHYOID MUSCLE
3.ANTERIOR BELLY OF DIGASTRIC
4.TENSOR TYMPANI
5.TENSOR VELI PALATINI

9. SENSORY ROOT
THE FIBRES ARISES FROM THE SEMILUNAR(TRIGEMINAL)
GANGLION.THE GANGLION IS LOCATED IN THE MECKELS
CAVITY.
THE THREE DIVISIONS OF SENSORY PART OF
TRIGEMINAL NERVE ARE;
1. OPHTHALMIC DIVISION(V1)
2. MAXILLARY DIVISION(V2)
3. MANDIBULAR DIVISION(V3)

12. OPHTHALMIC DIVISION
• PURELY SENSORY
• SMALLEST OF THREE
• LEAVES THE CRANIUM THROUGH SUPERIOR ORBITAL FISSURE
• SUPPLIES THE EYEBALL,CONJUCTIVA,LACRIMAL GLAND,MUCOUS
MEMBRANE OF NOSE ,PARANASAL SINUSES,SKIN OF
FOREHEAD,EYELIDS AND NOSE
• THREE BANCHES ARE:
1. FRONTAL
• SUPRATROCHLEAR
• SUPRA ORBITAL
2. LACRIMAL
3. NASOCILIARY
• BRANCHES IN THE ORBIT
• BRANCHES IN THE NASAL CAVITY
• TERMINAL BRANCHES ON FACE

13. • file:///.file/id=6571367.4478512

14. A.BRANCHES IN THE ORBIT
1. NERVE TO CILIARY GANGLION
2. LONG CILIARY NERVE
3. POSTERIOR ETHMOID NERVE
4. ANTERIOR ETHMOID NERVE
• INTERNAL NASAL BRANCHES
• EXTERNAL NASAL BRANCHES
B.BRANCHES IN THE NASAL CAVITY
SUPPLIES THE MUCOUS MEMBRANE OF NASAL CAVITY
C.TERMINAL BRANCHES ON FACE
SUPPLIES THE MEDIAL PART OF BOTH EYELIDS,LACRIMAL
SAC AND THE SKIN OVER THE SIDE OF THE BRIDGE OF THE NOSE

16. MAXILLARY DIVISION
• ARISES FROM MIDDLE OF TRIGEMINAL GANGLION
• INTERMEDIATE IN SIZE
• PURELY SENSORY
• LEAVES THE CRANIUM THROUGH FORAMEN
ROTUNDUM
• REACHES THE PTERYGOPALATINE FOSSA
• ENTERS ORBIT THROUGH INFERIOR ORBITAL
FISSURE
• COMES OUT THROUGH INFRA ORBITAL CANAL AND
INFRA ORBITAL FORAMEN AND DIVIDES INTO
TERMINAL BRANCHES

18. • IT SUPPLIES THE SKIN OF THE MIDDLE PORTION OF
THE FACE,SIDE OF NOSE, LOWER EYELID, UPPER LIP,
MAXILLARY TEETH AND PERIODONTAL TISSUES.
• IT ALSO SUPPLIES THE MUCOUS MEMBRANE OF
NASOPHARYNX, MAXILLARY SINUS, SOFT PALATE,
TONSIL AND HARD PALATE.
BRANCHES
1. IN THE MIDDLE CRANIAL FOSSA
THE MIDDLE MENINGEAL NERVE ALONG WITH THE
ARTERY,SUPPLYING THE DURA MATTER

19. 2. BRANCHES IN THE PTERYGOPALATINE FOSSA
A. THE ZYGOMATIC NERVE
I. ZYGOMATICOFACIAL
II. ZYGOMATICOTEMPORAL
B. PTERYGOPALATINE NERVES
I. ORBITAL BRANCH
II. NASAL BRANCH-POSTERIOR SUPERIOR LATERAL NASAL BRANCHES AND MEDIAL
OR SEPTAL BRANCHES
III. PALATINE BRANCHES-GREATER OR ANTERIOR,MIDDLE AND POSTERIOR FIBRES
C. POSTERIOR SUPERIOR ALVEOLAR BRANCHES
3. BRANCHES IN INFRA ORBITAL GROOVE AND CANAL
I. ANTERIOR SUPERIOR ALVEOLAR NERVE
II. MIDDLE SUPERIOR ALVEOLAR NERVE
4. BRANCHES ON FACE
I. INFERIOR PALPEBRAL
II. EXTERNAL NASAL
III. SUPERIOR LABIAL

20. MANDIBULAR DIVISION
• LARGEST DIVISION
• FORMED BY THE UNION OF LARGE SENSORY AND A SMALL
MOTOR ROOT
• THEY EMERGES OUT THE CRANIUM SEPERATELY THROUGH THE
FORAMEN OVALE
• THEY UNITE OUTSIDE THE SKULL
• THEN IT SPLITS INTO A SMALL ANTERIOR AND LARGE POSTERIOR
DIVISION
THE AREAS INNERVATED BY V3 ARE:
SENSORY ROOT SUPPLIES THE SKIN OVER THE TEMPORAL
REGION, AURICULE, EXTERNAL AUDITORY MEATUS, CHEEK, LOWER
LIP AND CHIN REGION.
MUCOUS MEMBRANE OF CHEEK, TONGUE, MASTOID CELLS,
MANDIBULAR TEETH AND PERIODONTAL TISSUES, BONE OF
MANDIBLE, TMJ AND PAROTID ARE SUPPLIED BY SENSORY PART.

22. MOTOR ROOT SUPPLIES
• THE MASTICATORY MUSCLES;
MASSETER, TEMPORALIS, MEDIAL AND LATERAL
PTERIGOID
• MYLOHYOID MUSCLE
• ANTERIOR BELLY OF DIGASTRIC
• TENSOR TYMPANI
• TENSOR VELI PALATINI
MANDIBULAR NERVE GIVES OFF BRANCHES IN 3
AREAS;
BRANCHES FROM THE UNDIVIDED PART:-

23. 1. NERVUS SPINOSUS:-IT ARISES OUTSIDE THE SKULL
AMD THEN REENTERS INTO THE MIDDLE CRANIAL
FOSSA TO SUPPLY THE DURA AND THE MASTOID AIR
CELLS
2. NERVE TO MEDIAL PTERYGOID MUSCLE
BRANCHES FROM THE DIVIDED PART:
ANTERIOR DIVISION:-THE ANTERIOR DIVISION IS
SMALLER THAN THE POSTERIOR.IT RECIEVES SENSORY
AND MOTOR FIBRES THAT SUPPLIES THE MUSCLES OF
MASTICATION,THE SKIN AND MUCOUS MEMBRANE OF
CHEEK,THE BUCCAL GINGIVA AND THE LOWER MOLARS
THE DIVISIONS ARE:-
1. NERVE TO LATERAL PTERYGOID
2. NERVE TO MASSETER MUSCLE

25. 3. NERVE TO TEMPORALIS MUSCLE
• ANTERIOR DEEP TEMPORAL NERVE
• POSTERIOR DEEP TEMPORAL NERVE
4. BUCCAL NERVE(LONG BUCCAL)
POSTERIOR DIVISION:- THE LARGEST POSTERIOR
DIVISION IS MAINLY SENSORY BUT ALSO CARRIES SOME
MOTOR COMPONENTS.THE BRANCHES ARE:-
1. AURICULOTEMPORAL NERVE:-ARISES AS TWO
ROOTS.UNITES INTO ONE BELOW THE FORAMEN
SPINOSUM ,SUPPLIES THE TRAGUS OF EAR AND THE
TEMPORAL REGION.
2. LINGUAL NERVE:-SECOND BRANCH OF POSTERIOR
DIVISION OF V3.

26. IT IS SENSORY TO THE ANTERIOR TWO-THIRD OF THE
TONGUE.IT PROVIDES BOTH GENERAL SENSATION AND
GUSTATORY SENSES.
3. INFERIOR ALVEOLAR NERVE:-IT IS THE LARGEST
BRANCH OF POSTERIOR DIVISION.WITHIN THE
MANDIBLE THE INFERIOR ALVEOLAR NERVE DECENDS
IN THE INFERIOR ALVEOLAR CANAL AND IS DISTRIBUTED
THROUGH OUT THE MANDIBLE.IT ACCOMPANIES THE
INFERIOR ALVEOLAR ARTERY.IT SUPPLIES THE LOWER
TEETH AND PERIODONTAL TISSUES.
4. MENTAL NERVE:-AS THE INFERIOR ALVEOLAR NERVE
REACHES THE REGION OF MENTAL FORAMEN,IT DIVIDES
INTO TWO TERMINAL BRANCHES
IT SUPPLIES THE SKIN OF THE CHIN AND MUCOUS
MEMBRANE OF THE LOWER LIP.

28. 5. INCISIVE BRANCHES:-IT SUPPLIES THE CUSPID
TOOTH AND THE INCISORS.
6. MYLOHYOID NERVE:-BEFORE THE INFERIOR
ALVEOLAR NERVE ENTERS THE MANDIBULAR
FORAMEN, IT GIVES OFF A BRANCH,THE MYLOHYOID
BRANCH,WHICH IS BOTH SENSORY AND MOTOR.IT
SUPPLIES THE ANTERIOR BELLY OF DIGASTRIC AND
THE MYLOHYOID MUSCLE.

29. CLINICALANATOMY
• CLINICAL TESTING OF THE MOTOR PART OF THE
MANDIBULAR NERVE.
• REFERRED PAIN.
• LINGUAL NERVE LIES IN CONTACT WITH MANDIBLE,
MEDIAL TO THE THIRD MOLAR TOOTH.
• MANDIBULAR NERVE INNERVATES A PORTION OF
EXTERNAL EAR AND LOWER TEETH, SO THE PAIN
OF LOWER TEETH MAY REFERRED TO EAR.

30. • LESION AT FORAMEN OVALE LEADS TO
PARESTHESIAS ALONG THE MANDIBLE , TONGUE ,
TEMPORAL REGION AND PARALYSIS OF THE
MUSCLES OF MASTICATION. THIS LEADS TO LOSS OF
JAW-JERK REFLEX.
• FREY’S SYNDROME : SWEATING AND CROCODILE
TEARS.
• TRIGEMINAL NEURALGIA(TIC DOULOUREUX ,
TRIFACIAL NEURALGIA , FOTHERGILL’S DISEASE)
TRIGGER ZONES:-VERMILION BORDER OF
THE LIPS, THE ALAE OF THE NOSE, THE CHEEKS,
AROUND THE EYES.

31. REFERENCES
• HANDBOOK OF LOCAL ANESTHESIA-6TH EDITION
-STANLEY F MALAMED
• MONHEIM’S LACAL ANESTHESIA AND PAIN CONTROL
IN DENTAL PRACTICE-7TH EDITION
• INTERNET