This document provides an overview of the tongue and hypoglossal nerve. It begins with the contents and introduction, describing the tongue's location, shape, and functions. It then covers the tongue's development, gross features including its parts and nerve supply. The document details the muscles of the tongue and their nerve supply, as well as the tongue's movement, blood supply, lymphatic drainage, and histology. It concludes with the clinical aspects of various tongue conditions and lesions of the hypoglossal nerve, along with multiple choice questions.

1. Tongue and hypoglossal nerve
Presenter- Yashu Bhardwaj
8/18/2023

2. Contents
• Introduction
• External Features
• Development of tongue
• Gross features
• Nerve Supply
• Muscles of Tongue
• Movement of tongue
• Blood supply
• Lymphatic drainage
• Histology of tongue
• Clinical aspects
• Hypoglossal nerve
• Clinical corelations
• MCQ
• References
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3. Introduction
• Mobile muscular organ in oral cavity.
• Separated from teeth by  deep alveololingual sulcus.
• Conical in shape  elongated posteroanteriorly & flattened
dorsoventrally.
• Functions:
1. Taste.
2. Speech.
3. Mastication.
4. Deglutition.
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4. General features
• Function : taste , speech , deglutition,
• Parts : tip, body , root
• Presence of median sulcus
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5. Formation of Anterior 2/3rd of Tongue
• Tuberculum Impar: middle of the
mandibular process.
• Lingual swelling:.
• forms mucous membrane of ant
2/3rd of the tongue.
• These merge with each other and
the tuberculum impar to form
mucous membrane of the anterior
2/3rd of the tongue is formed

6. Formation of Posterior 1/3rd of Tongue
• Root of the tongue arises from
large midline swelling develops
from mesenchyme of 2nd, 3rd,
and 4th arches.
• Copula or Hypobrachial eminence

7. • Muscles of the tongue
• arises from the occipital
somites.
• Migrated forward in to the
tongue area.
• Nerve supply hypoglossal
nerve.

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9. Dorsal surface
 Convex
 Presence of median furrow.
 Sulcus termanalis divides it into 2 parts :
• Anterior 2/3rd (oral /presulcal part)
• Posterior 1/3rd (pharyngeal / postsulcal part )
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10. External Features
Anterior two-third: oral
part.
Posterior one-third:
pharyngeal part.
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11. Presulcal Part (Oral)
 Anterior 2/3rd develops from 1st
pharyngeal arch.
 Epithelium : Keratinised stratified
squamous epithelium
 Features:-
• A median furrow representing bilateral
origin of tongue.
 Four types of papillae (lingual papillae)-
• Filiform papillae
• Fungiform papillae
• Circumvallate papillae
• Foliate papillae
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12. Postsulcal Part (Pharyngeal)
• Posterior 1/3rd develops from 3rd and
4th pharyngeal arches.
• Epithelium : Non keratinised st.
squamous epithelium.
• Forms base of tongue.
• Forms anterior wall of oropharynx.
• Lingual tonsil:
Lymphoid follicles are present in
mucosa.
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13. Ventral surface
• Reflected on floor of mouth. Frenulum linguae : May be seen through mucus
membrane on either sides of frenulum linguae( lingual nerve and lingual artery
are medial to vein but not visible)
• Plica Fimbriata : lateral to lingual vein directed forward ,medial and towards
tip of tongue.
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14. 14
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15. 15
Nerve Supply
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16. Nerve Supply
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17. Motor Supply-
• All muscles of tongue are supplied by Hypoglossal Nerve except
Palatoglossus.
• Palatoglossus is supplied by cranial root of Accessory Nerve.
Sensory Supply-
Anterior 2/3rd –
General Sensations- Lingual Nerve
Special Sensations of Taste- Chorda Tympani Nerve [except circumvallate
papillae which are supplied by Glossopharyngeal Nerve.
Posterior 2/3rd –
General Sensations & Special Sensations of Taste- Glossopharyngeal Nerve.
Posterior-most part- Internal Laryngeal Nerve.
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18. Extrinsic muscles
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Genioglossus arises from mandible & protrudes the tongue. It is also known
as "safety muscle" only muscle that propels the tongue forward.
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19. Extrinsic muscles of tongue
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20. Muscles of Tongue
• Intrinsic muscles
1. Superior longitudinal.
2. Inferior longitudinal.
3. Transverse.
4. Vertical.
• Extrinsic muscles
1. Genioglossus.
2. Hyoglossus.
3. Styloglossus.
4. Palatoglossus.
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21. Muscles of tongue
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22. Movements of tongue
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23. Blood Supply
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24. Arterial Supply
• Lingual artery: 3 parts
• deep lingual artery to anterior
part , Dorsal lingual artery to
posterior part.
• Tonsillar branch of facial artery.
• Ascending pharyngeal artery.
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25. Venous drainage
• Deep lingual vein:
principle vein
• Venae comitantes with
lingual artery which
adjoins dorsal lingual
vein.
• Venae comitantes
accompanying
hypoglossal nerve.
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26. Lymphatic drainage
• Tip : submental & jugulo omohyoid
lymph nodes
• Lateral : Ipsilateral ,
Submandibular & deep cervical
lymph nodes.
• Central portion & base : Deep
cervical lymph nodes
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27. Lymphatic Drainage
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28. Drawing H&E 40x
1. Stratified squamous
epithelium
2. Lamina propria
3. Skeletal muscle
4. Serous gland
5. Mucous gland
6. Adipose tissue
7. Smooth ventral
surface of tongue
P. Papillae

30. A. Filliform; B. Fungiform
C. Circumvallate; D. Foliate

33. Taste Buds

36. Clinical Aspects
• Glossitis
• Ankyloglossia ( tongue tie)
• Lichen planus
• Geographical tongue
• Hairy tongue
• Fissured tongue
• Aglossia
• Microglossia
• Oral cancer
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37. Glossitis
Affected Normal
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tongue is swollen and
inflamed

38. Lichen Planus
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• Appear as white, lacy patches
• Red, swollen tissues
• These lesions may cause
burning, pain or other discomfort.

39. Fissured tongue
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A benign condition
affecting the top surface of
the tongue

40. Hairy tongue
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Black, hairy tongue is a harmless
condition. It's caused by a build-up
of dead skin cells on the tiny
projections that contain taste buds
(papillae).

41. Bifid Aglossia
Bifid or cleft tongue is a tongue with a
split running lengthwise along tip of
tongue. It results of incomplete fusion of
distal tongue.
Congenital defect resulting in a partial
development or complete absence of a
tongue. Commonly associated with
craniofacial & limb defects.
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42. Clinical
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Ankyloglossia/ tongue-tie
Paralysis
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43. Ludwig’s angina
• Cellulitis of floor of mouth usually
due to infection from a tooth,
causing inflammatory edema of
floor of mouth. Tongue is pushed
upwards due to edema with pain.
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44. Hypoglossal Nerve
• Motor nerve, supply muscles of
tongue except Palatoglossus.
• Arises from hypoglossal nuclei.
• Functional components: GSE
(hypoglossal nuclei)

46.  Branches containing C1 fibres:
• Meningeal branch : duramatar of posterior cranial fossa.
• Nerve to thyrohyoid : crosses greater cornu of hyoid bone
• Nerve to geniohyoid : arises from above hyoid bone.
• Descendens hypoglossi & upper root of ansa cervicalis: joins
inferior root of ansa cervicalis at the level of cricoid cartilage.

47. Lesions of hypoglossal nerve
• If hypoglossal nerve is cut on one side,
there will be lower motor neuron type of
paralysis of muscles of the tongue on
that side.
• On asking patient to protrude his
tongue, tip of tongue deviates to
paralyzed side due to unopposed
action of muscles of healthy side.

48. MCQ
1.) There are intrinsic and extrinsic group of muscle which helps in
movement of tongue. Which muscle is considered as safety muscle
of tongue?
A.) Genioglossus.
B.) Hyoglossus.
C.) Styloglossus.
D.) Palatoglossus
Ans: A
Ref: Vishram Singh Textbook of Anatomy Head & Neck, Pg- 192
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49. 2.) Cellulitis of floor of mouth usually due to infection from a carious molar
tooth, causing inflammatory edema of floor of mouth. Tongue is pushed
upwards due to edema with pain. Such condition is known as:
A.) Winsons angina
B.) Ludwig’s angina
C.) Ranula
D.) Quinsy
Ans: B
Ref: Vishram Singh Textbook of Anatomy Head & Neck, Pg- 189
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50. 3.) Which clinical condition is showing in given picture?
A.) Microglossia
B.) Macroglossia
C.) Ankyloglossia
D.) Bifid of tongue
Ans: C
Ref: Vishram Singh Textbook of Anatomy Head & Neck, Pg- 191
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51. 4.) A patient reached to the clinic having right side deviated tongue. Which
diagnosis related to this condition is correct?
A.) Paralysis of left genioglossus.
B.) Paralysis of right genioglossus.
C.) Paralysis of left Hyoglossus
D.) Paralysis of right Hyoglossus
Ans: B
Ref: Vishram Singh Textbook of Anatomy Head & Neck, Pg- 189
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52. 5 In which nucleus, special visceral afferent fibre from post 1/3rd of
tongue relay?
A.) Spinal nucleus of trigeminal
B.) Nucleus ambiguus
C.) Nucleus tractus solitarius
D.) Dorsal nucleus of vagus
Ans: C
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