Tongue
Highly muscular organ of Deglutition, taste and speech.
● Divided in two parts by Sulcus
Terminalis(V shaped) with median
depressionForamenCaecum [upper end
of embryonic thyroid diverticulum
(thyroglossal duct).
1. oral ( presulcal) part- anterior ⅔ rd. papilla present here.
2. pharyngeal(post sulcal part)- posterior ⅓ rd. devoid of papillae.
Muscles of Tongue:
1. Intrinsic: superior and inferior
longitudinal, transverse and vertical
2. Extrinsic: 4 pair of muscles
a) Genioglossus- protrude its apex from
mouth, also diverses tongue to
opposite side.
b) Hyoglossus- depresses tongue.
c) Styloglossus- up and backward
movement.
d) Palatoglossus- elevates root of tongue.
Chondroglossus- also present nearly similar to hyoglossus but has separate fibers.
Note: All muscles of tongue supplied by Hypoglossal nerve except Palatoglossus.
Palatoglossus is supplied by pharyngeal plexus (formed by IX, X and superior cervical sympathetic ganglia).
Arterial supply:
Lingual artery- branch from anterior
surface of external carotid artery.
3 branches:
dorsal lingual,
sublingual and
deep lingual artery.
Venous Drainage:
Lingual veins
Joins facial and anterior division of
Retromandibular vein to form common
facial vein.
Finally drains into Internal jugular vein.
Lymphatic Drainage:
Lingual tonsils
present in mucosa of pharyngeal part of
dorsal surface Of tongue
lymphatic vessels.
Anterior part drain in-
marginal and central vessels
Posterior part drain in -
Dorsal lymph vessels
Central part drain in-
bilaterally- important to dissect both
side in malignancy.
Finally all drain in submental, submandibular, jugulo-omohyoid and jugulo-digastric nodes.
Sensory Innervation of tongue (for general sensation):
Anterior 2/3rd-
Lingual Nerve branch of mandibular
division of trigeminal nerve.
Posterior 1/3rd-
Glossopharyngeal nerve.
Near valleculae-
Internal laryngeal branch of Vagus.
Taste:
Salt( NaCl), Sour(acidic),Sweet(sugar), Bitter( quinine) and Umami( delicious taste)
Innervation of Tongue for Taste sensation:
1. Chorda Tympani-
A branch of VIIth nerve, travels via
Lingual nerve & supplies anterior
part of tongue excluding circumvallate
papillae.
Note: Lingual nerve gives only sensory innervation- no taste sensation.
2. Facial nerve-
also innervates inferior part of soft palate
for taste sensation.
3. Glossopharyngeal nerve-
Taste sensation in circumvallate papillae,
post sulcal part of Tongue , palatoglossal
arch and oropharynx.
4. Vagus Nerve-
Extreme pharyngeal part of tongue and
epiglottis via internal laryngeal branch.
Thank you all,
Questions and suggestions are always welcomed.
Dr. Rajesh Kumar
Resident
Department of Anatomy
AIIMS, New Delhi
Highly muscular organ of Deglutition, taste and speech.
● Divided in two parts by Sulcus
Terminalis(V shaped) with median
depressionForamenCaecum [upper end
of embryonic thyroid diverticulum
(thyroglossal duct).
1. oral ( presulcal) part- anterior ⅔ rd. papilla present here.
2. pharyngeal(post sulcal part)- posterior ⅓ rd. devoid of papillae.
Muscles of Tongue:
1. Intrinsic: superior and inferior
longitudinal, transverse and vertical
2. Extrinsic: 4 pair of muscles
a) Genioglossus- protrude its apex from
mouth, also diverses tongue to
opposite side.
b) Hyoglossus- depresses tongue.
c) Styloglossus- up and backward
movement.
d) Palatoglossus- elevates root of tongue.
Chondroglossus- also present nearly similar to hyoglossus but has separate fibers.
Note: All muscles of tongue supplied by Hypoglossal nerve except Palatoglossus.
Palatoglossus is supplied by pharyngeal plexus (formed by IX, X and superior cervical sympathetic ganglia).
Arterial supply:
Lingual artery- branch from anterior
surface of external carotid artery.
3 branches:
dorsal lingual,
sublingual and
deep lingual artery.
Venous Drainage:
Lingual veins
Joins facial and anterior division of
Retromandibular vein to form common
facial vein.
Finally drains into Internal jugular vein.
Lymphatic Drainage:
Lingual tonsils
present in mucosa of pharyngeal part of
dorsal surface Of tongue
lymphatic vessels.
Anterior part drain in-
marginal and central vessels
Posterior part drain in -
Dorsal lymph vessels
Central part drain in-
bilaterally- important to dissect both
side in malignancy.
Finally all drain in submental, submandibular, jugulo-omohyoid and jugulo-digastric nodes.
Sensory Innervation of tongue (for general sensation):
Anterior 2/3rd-
Lingual Nerve branch of mandibular
division of trigeminal nerve.
Posterior 1/3rd-
Glossopharyngeal nerve.
Near valleculae-
Internal laryngeal branch of Vagus.
Taste:
Salt( NaCl), Sour(acidic),Sweet(sugar), Bitter( quinine) and Umami( delicious taste)
Innervation of Tongue for Taste sensation:
1. Chorda Tympani-
A branch of VIIth nerve, travels via
Lingual nerve & supplies anterior
part of tongue excluding circumvallate
papillae.
Note: Lingual nerve gives only sensory innervation- no taste sensation.
2. Facial nerve-
also innervates inferior part of soft palate
for taste sensation.
3. Glossopharyngeal nerve-
Taste sensation in circumvallate papillae,
post sulcal part of Tongue , palatoglossal
arch and oropharynx.
4. Vagus Nerve-
Extreme pharyngeal part of tongue and
epiglottis via internal laryngeal branch.
Thank you all,
Questions and suggestions are always welcomed.
Dr. Rajesh Kumar
Resident
Department of Anatomy
AIIMS, New Delhi
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