Anatomy of the Tongue by Baasir Umair.pptx

Anatomy and Nervous Supply of the Tongue
Presentation Overview
This PowerPoint presentation provides a detailed anatomical and neurovascular description of the tongue, covering:
• General Anatomy (Structure, Location, and Parts)
• Muscle Classification (Intrinsic & Extrinsic)
• Papillae of the Tongue (Types & Functions)
• Arterial and Venous Drainage
• Lymphatic Supply
• Nervous Supply (Motor & Sensory)
• Development of the Tongue
• Clinical Correlations
This presentation is designed for medical students, professionals, and anatomy enthusiasts to enhance their understanding of the tongue's anatomy and functions.
1. Anatomy of the Tongue
The tongue is a muscular organ located in the oral cavity, primarily responsible for taste, speech, mastication, and deglutition. It is covered with mucosa, containing numerous taste buds and papillae that contribute to its sensory functions.
1.1 Location of the Tongue
• The tongue extends from the hyoid bone in the center of the neck to the floor of the mouth.
• It is attached posteriorly to the styloid process and the soft palate.
• Inferiorly, it connects to the mandible and hyoid bone.
2. Parts of the Tongue
The tongue is divided into three main parts:
1. Tip (Apex): The most anterior and mobile part.
2. Body: The central region, covered with papillae and taste buds.
o The ventral (inferior) surface is smooth and connected to the lingual frenulum.
o The dorsal (superior) surface is rough and interacts with the palate.
3. Base (Root): The most posterior part, housing lingual tonsils and foliate papillae.
Divisions of the Tongue
• The sulcus terminalis divides the tongue into:
o Anterior 2/3 (Oral Part)
o Posterior 1/3 (Pharyngeal Part)
• The foramen cecum, a small depression, marks the embryological remnant of the thyroglossal duct.
3. Papillae of the Tongue
The dorsal surface of the tongue contains four types of papillae, responsible for taste and sensation:
3.1 Circumvallate Papillae
• Largest in size but least numerous.
• Located anterior to the sulcus terminalis.
• Contain taste buds and are innervated by the Glossopharyngeal Nerve (CN IX), despite being in the anterior 2/3 region.
3.2 Fungiform Papillae
• Mushroom-shaped, scattered on the anterior 2/3 of the tongue.
• Contain taste buds.
• Innervated by the Facial Nerve (CN VII) via Chorda Tympani.
3.3 Foliate Papillae
• Located on the posterolateral sides of the tongue.
• Contain taste buds.
3.4 Filiform Papillae
• Most numerous but do not contain taste buds.
• Provide mechanical function by enhancing friction between food and the tongue.
4. Muscles of the Tongue
The tongue consists of two muscle groups:
4.1 Intrinsic Muscles (Shape and Movement)
• Superior Longitudinal
• Inferior Longitudinal
• Transverse
• Vertical
4.2 Extrinsic Muscles (Positioning and Function)
• Genioglossus
• Hyoglossus
• Styloglossus
• Palatoglossus
Each muscle has a specific origin, insertion, course, and function that aids in swallowing, articulation, and movement of the tongue.

1. Anatomy of the Tongue By Baasir Umair MPhil in Pharmacology [email protected] 3/20/2025 Baasir Umair 1

2. Contents: Introduction of Tongue Anatomy Development of Tongue Developmental Abnormalities Parts of the Tongue Division of the Tongue Dorsal Surface Ventral Supply Muscle of the Tongue Vasculature of the Tongue 3/20/2025 Baasir Umair 2

3. The tongue (Lingua or Glossa ) is a muscular organ located on the floor of the mouth in most vertebrates. The word "tongue" originates from Old English ‘ tunge ’, derived from Proto-Germanic ‘ tungōn ’. It is a movable and flexible structure composed of intrinsic and extrinsic muscles. The tongue is coated by mucosa, a wet, pink tissue that protects its surface. It plays a crucial role in licking, tasting, breathing, swallowing, and speaking. As part of the digestive system, it helps in chewing (mastication) and swallowing (deglutition) by manipulating food. It is the primary organ of taste, containing specialized structures called taste buds. The rough texture of the tongue is due to the presence of papillae, which house the taste buds. The tongue has numerous nerves that transmit taste sensations to the brain. Anatomy of the Tongue 3/20/2025 Baasir Umair 3

4. The tongue is one of the main muscular organs in the oral cavity. The dorsum (upper surface) of the tongue is covered with numerous lingual papillae, which contain taste buds. It has many nerves and blood vessels, making it a highly sensitive organ. Saliva keeps the tongue moist, aiding in its functions. The tongue plays a role in the natural tooth-cleaning process. It is essential for speech production in humans and vocalization in other species. Anatomy of the Tongue 3/20/2025 Baasir Umair 4

5. Anatomy of the Tongue 3/20/2025 Baasir Umair 5

6. The tongue (Lingua or Glossa ) is a pinkish, muscular organ located in the oral cavity of the mouth. It plays a vital role in taste perception, speech, chewing (mastication), swallowing (deglutition), and natural oral cleaning. Location of the Tongue The tongue extends from the hyoid bone, located in the center of the neck, to the floor of the mouth. The root of the tongue is connected: Posteriorly to the styloid process and soft palate. Inferiorly to the mandible and hyoid bone. Anatomy of the Tongue 3/20/2025 Baasir Umair 6

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9. Anatomy of the Tongue Development of the Tongue The tongue develops from the pharyngeal arches during the 4th to 8th week of embryonic development. It arises from multiple swellings in the floor of the primitive pharynx and undergoes complex differentiation. Embryological Origin: The tongue originates from the first four pharyngeal arches. Different parts of the tongue develop from specific arches: Anterior two-thirds → First pharyngeal arch Posterior one-third → Third and part of the fourth pharyngeal arch Epiglottis and extreme posterior part → Fourth pharyngeal arch 3/20/2025 Baasir Umair 9

10. Anatomy of the Tongue 1. Development of the Anterior Two-Thirds (Oral Part) Forms from the first pharyngeal arch. Develops as two lateral lingual swellings and a median swelling (tuberculum impar ). The lateral lingual swellings enlarge and fuse, forming the oral part of the tongue. This part is covered by ectoderm. The sulcus terminalis marks the boundary between the anterior and posterior parts. 2. D evelopment of the Posterior One-Third (Pharyngeal Part) Forms from the third and part of the fourth pharyngeal arches. Develops from a large midline swelling called the hypopharyngeal eminence. The third arch component overgrows the second arch, leading to its regression. This part is covered by endoderm. 3/20/2025 Baasir Umair 10

11. Anatomy of the Tongue 3. Development of the Epiglottis and Extreme Posterior Part: Forms from the fourth pharyngeal arch. Develops from the posterior part of the hypopharyngeal eminence. Gives rise to the epiglottis and the extreme posterior region of the tongue. 3/20/2025 Baasir Umair 11

12. Anatomy of the Tongue Ankyloglossia (Tongue-Tie) : Ankyloglossia (tongue-tie) is the general clinical term for the short lingual frenulum (less than 2 cm), that limits the range of movement of the tongue, This is associated with speech development disorders and feeding disorders. In the most common form of ankyloglossia , the frenulum extends to the tip of the tongue. 3/20/2025 Baasir Umair 12

13. Anatomy of the Tongue Macroglossia : Macroglossia is the medical term for an unusually large tongue. Sever enlargement of the tongue can cause cosmetic and functional difficulties in speaking, eating, swallowing and sleeping. Macroglossia is uncommon, and usually occurs in children. There are many causes can be associated with a number of genetic abnormalities including: trisomy 21 (Down syndrome), acromegaly. Treatment is dependent upon the exact cause. 3/20/2025 Baasir Umair 13

14. Anatomy of the Tongue Microglossia : This is a condition where the size of the tongue is abnormally small. Cases of complete absence of the tongue have been reported. Fortunately, it is a rare condition. Obviously, a tiny tongue will pose many difficulties related to speech and swallowing. There is no treatment for this condition, and the affected person will have to train their tongue to the best of their abilities 3/20/2025 Baasir Umair 14

15. Anatomy of the Tongue Thyroglossal cyst: A thyroglossal cyst may lie at any poínt along the migratory pathway of the thyroid gland but is always near or in the midline of the neck. It is a cystic remnant of the thyroglossal duct. Although approximately 50% of these cysts are close to or just inferior to the body of the hyoid bone , they may also be found at the base of the tongue or close to the thyroid cartilage. Sometimes, a thyroglossal cyst is connected to the outside by a fistulous canal, a thyroglossal fístula . Such a fistula usually arises secondarily after rupture of a cyst but may be present at birth. 3/20/2025 Baasir Umair 15

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17. Anatomy of the Tongue Anatomical Features of the Dorsal Surface 3/20/2025 Baasir Umair 17

18. Divisions of the Tongue The tongue is divided into two main sections by a V-shaped groove called the sulcus terminalis : Anterior Two-Thirds (Oral Part) Lies in the oral cavity. Contains taste buds and lingual papillae. Plays a major role in mastication, articulation, and taste sensation. Posterior One-Third (Pharyngeal Part) Lies in the oropharynx. Covered by lingual tonsils, contributing to immune defense. Less mobile and involved in swallowing rather than taste. Anatomy of the Tongue 3/20/2025 Baasir Umair 18

19. Anatomy of the Tongue Sulcus Terminalis : The sulcus terminalis is a V-shaped groove on the dorsal surface of the tongue, marking the boundary between: The anterior two-thirds (oral part) and The posterior one-third (pharyngeal part) of the tongue. Function of Sulcus Terminalis It serves as a landmark dividing the tongue into its oral and pharyngeal parts. It helps in distinguishing the papillae-covered anterior portion from the lymphoid tissue of the posterior portion. 3/20/2025 Baasir Umair 19

20. Anatomy of the Tongue Foramen Cecum: The foramen cecum is a small, pit-like depression located at the midpoint of the sulcus terminalis . Embryological Significance: It is a remnant of the thyroglossal duct, which is an embryological structure from which the thyroid gland develops. During fetal development, the thyroid gland originates at the foramen cecum and migrates down to its final position in the neck . Clinical Relevance: In some cases, thyroglossal cysts may form along the path of the thyroglossal duct if it does not completely regress. 3/20/2025 Baasir Umair 20

21. Anatomy of the Tongue: Dorsal Surface 3/20/2025 Baasir Umair 21

22. Anatomy of the Tongue Parts of the Tongue The average length of the tongue is about 10 cm, though individual variation exists. On average: In men, the tongue is approximately 3.3 inches (8.4 cm) long. In women, the tongue is approximately 3.1 inches (7.9 cm) long. The tongue is divided into three main parts: 1. Tip (Apex) The front-most and most movable portion of the tongue. Plays a key role in licking, tasting, and articulation. 3/20/2025 Baasir Umair 22

23. Anatomy of the Tongue Parts of the Tongue 2. Body The middle section of the tongue. Divided into two distinct surfaces: Ventral (Inferior) Surface: Smooth and connected to the floor of the oral cavity by the lingual frenulum. Dorsal (Superior) Surface: Rough, covered in taste buds and lingual papillae, and positioned against the palate. 3/20/2025 Baasir Umair 23

24. Anatomy of the Tongue Parts of the Tongue 3. B ase (Root of the Tongue) The posterior-most portion, extending into the oropharynx. Features: Covered with foliate papillae along the posterolateral surface. Contains lingual tonsils, which are lymphoid aggregates involved in immune defense. Connected to the epiglottis, which prevents food from entering the airway during swallowing. Posteriorly attached to the styloid process and soft palate. Inferiorly attached to the mandible and hyoid bone. 3/20/2025 Baasir Umair 24

25. Anatomy of the Tongue Papillae of the Tongue The dorsal surface of the tongue is covered with lingual papillae, which are small mucosal projections involved in taste perception and mechanical functions. There are four types of papillae, out of which all contain taste buds except filiform papillae. 3/20/2025 Baasir Umair 25

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28. Anatomy of the Tongue Papillae of the Tongue Types of Lingual Papillae 1. Circumvallate ( Vallate ) Papillae Shape: Large, dome-shaped , arranged in a V-shape . Location: Positioned at the posterior part of the tongue , just anterior to the sulcus terminalis . Arranged in an inverted V-pattern ( 8-12 in number ). Function: Contain numerous taste buds , mainly for detecting bitter taste . Surrounded by deep trenches , where Von Ebner’s glands secrete serous fluid to cleanse taste buds and enhance taste perception. Clinical Significance: Enlargement of vallate papillae can occur due to infection or irritation , sometimes mistaken for pathology. 3/20/2025 Baasir Umair 28

29. Anatomy of the Tongue Papillae of the Tongue Types of Lingual Papillae: 2. Filiform Papillae (Does NOT contain taste buds) Shape: Slender, conical, or thread-like projections. Location: Most numerous papillae, covering the anterior two-thirds of the tongue . Function: Mechanical function: Provides friction for handling food. No taste buds: These papillae do not play a role in taste perception. Appearance: Whitish due to keratinization. Heavily keratinized in animals (e.g., cats) for grooming. 3/20/2025 Baasir Umair 29

30. Anatomy of the Tongue Papillae of the Tongue 3. Fungiform Papillae Shape: Mushroom-shaped , larger than filiform papillae. Location: Scattered between filiform papillae on the anterior two-thirds of the tongue. More concentrated at the tip and lateral borders . Contain Pedicel and large round head Function: Contain taste buds for detecting sweet, sour, salty, and umami flavors. Rich in blood supply, giving them a reddish appearance. 3/20/2025 Baasir Umair 30

31. Anatomy of the Tongue Papillae of the Tongue 4. Foliate Papillae Shape: Leaf-like ridges on the sides of the tongue. Location: Found on the posterolateral surface of the tongue. More prominent in infants and young children, but may regress with age. Usually 4-5 in number. Function: Contain numerous taste buds that detect sour taste. Associated with Von Ebner’s glands, which help in taste perception. Clinical Significance: Can sometimes be mistaken for lesions or abnormal growths, leading to unnecessary concern. 3/20/2025 Baasir Umair 31

32. Anatomy of the Tongue Type Shape Location Function Taste Buds Circumvallate Large, dome-shaped V-shaped row at back Detects bitter taste ✅ Yes Filiform Thin, thread-like Anterior two-thirds Provides friction, no taste function ❌ No Fungiform Mushroom-shaped Scattered, mostly at tip Detects sweet, sour, salty, umami ✅ Yes Foliate Leaf-like ridges Lateral borders of tongue Detects sour taste ✅ Yes 3/20/2025 Baasir Umair 32

33. Anatomy of the Tongue Muscles of the Tongue 3/20/2025 Baasir Umair 33

34. Anatomy of the Tongue Muscles of the Tongue 3/20/2025 Baasir Umair 34

35. Anatomy of the Tongue Muscles of the Tongue 3/20/2025 Baasir Umair 35

36. Anatomy of the Tongue Muscles of the Tongue 3/20/2025 Baasir Umair 36

37. Muscles of the Tongue 3/20/2025 Baasir Umair 37

38. Muscles of the Tongue Muscle Origin Insertion Function Intrinsic Muscles Superior Longitudinal Near epiglottis, median septum Tongue margins & mucosa Elevates & curls tongue tip Inferior Longitudinal Root of tongue, hyoid bone Apex of tongue Depresses & retracts tongue Transverse Median fibrous septum Lateral tongue borders Narrows & elongates tongue Vertical Dorsal tongue surface Inferior tongue surface Flattens & widens tongue Extrinsic Muscles Genioglossus Mental spine of mandible Tongue & hyoid bone Protrudes & depresses tongue Hyoglossus Hyoid bone Lateral tongue Depresses & retrudes tongue Styloglossus Styloid process of temporal bone Side of tongue Retracts & elevates tongue Palatoglossus Palatine aponeurosis Lateral tongue Elevates posterior tongue 3/20/2025 Baasir Umair 38

39. Tongue Vasculature 3/20/2025 Baasir Umair 39

40. Muscles of the Tongue Category Main Vessel Branches/Subdivisions Regions Supplied/Drained Arterial Supply Lingual Artery (From External Carotid) Dorsal Lingual Arteries - Deep Lingual Artery - Sublingual Artery - Accessory Pharyngeal Artery - Tonsillar Artery Dorsal Lingual: Root of the tongue - Deep Lingual: Anterior 2/3 of tongue Sublingual: Floor of mouth, sublingual gland - Accessory Pharyngeal: Soft palate & pharyngeal region Tonsillar : Palatine tonsil & posterior tongue Venous Drainage Lingual Veins → Internal Jugular Vein Dorsal Lingual Vein - Deep Lingual Vein - Sublingual Vein Dorsal Lingual: Drains dorsum & root Deep Lingual: Drains body & tip Sublingual : Drains floor of the mouth Lymphatic Drainage Juguloomyohyoid Nodes (Collective Lymph Drainage) Submental Nodes - Submandibular Nodes - Deep Cervical Nodes ( Jugulodigastric ) Tip : Submental - Anterior 2/3 Lateral Submandibular - Anterior 2/3 Medial Deep Cervical - Posterior 1/3: Jugulodigastric 3/20/2025 Baasir Umair 40

41. Tongue Nerve Supply 3/20/2025 Baasir Umair 41

42. Tongue Nerve Supply Category Region Nerve Branch Function Motor Supply Entire tongue (except Palatoglossus) Hypoglossal Nerve (CN XII) - Controls all intrinsic and extrinsic muscles, except Palatoglossus Palatoglossus Muscle Vagus Nerve (CN X) Pharyngeal Branch Controls Palatoglossus, which elevates the tongue Sensory Supply (General Sensation: Touch, Pain, Temperature) Anterior 2/3 Trigeminal Nerve (CN V3 - Mandibular Division) Lingual Nerve Provides general sensation to the anterior 2/3 of the tongue Posterior 1/3 Glossopharyngeal Nerve (CN IX) Lingual Branch Provides general sensation to the posterior 1/3 of the tongue Epiglottis & Base of Tongue Vagus Nerve (CN X) Internal Branch of Superior Laryngeal Nerve Provides general sensation to the epiglottis and base of the tongue Sensory Supply (Special Sensation: Taste) Anterior 2/3 (Except Circumvallate Papillae) Facial Nerve (CN VII) Chorda Tympani (via Lingual Nerve) Provides taste sensation to the anterior 2/3 of the tongue Posterior 1/3 & Circumvallate Papillae (Exception) Glossopharyngeal Nerve (CN IX) Lingual Branch Provides taste sensation to the posterior 1/3 of the tongue and circumvallate papillae (which are in anterior 2/3 but innervated like posterior 1/3) Epiglottis & Base of Tongue Vagus Nerve (CN X) Internal Branch of Superior Laryngeal Nerve Provides taste sensation from the epiglottis 3/20/2025 Baasir Umair 42

43. Anatomy of the Tongue: Inferior Surface 3/20/2025 Baasir Umair 43

44. Anatomy of the Tongue Anatomical Features of the Inferior Surface 3/20/2025 Baasir Umair 44

45. Anatomy of the Tongue Inferior Part of the Tongue The inferior part (ventral surface) of the tongue refers to the underside of the tongue, which is smooth, thin, and highly vascularized. Unlike the dorsal surface, which is rough due to the presence of papillae, the ventral surface is smooth and covered with a thin mucous membrane. 3/20/2025 Baasir Umair 45

46. Anatomy of the Tongue Anatomical Features of the Inferior Surface 1. Lingual Frenulum: A thin mucosal fold that connects the ventral surface of the tongue to the floor of the mouth. It limits excessive movement of the tongue while allowing flexibility. Clinical significance: Ankyloglossia (tongue-tie): A condition where the frenulum is too short or tight, restricting tongue movement. 2. Deep Lingual Veins: Prominent blue-colored veins visible through the thin mucosa of the ventral surface. These veins aid in rapid absorption of sublingual medications (e.g., nitroglycerin for angina). 3/20/2025 Baasir Umair 46

47. Anatomy of the Tongue Anatomical Features of the Inferior Surface 3. Sublingual Folds (Plica Sublingualis ): A raised fold of mucosa on either side of the frenulum. It contains the openings of the submandibular and sublingual salivary glands, which secrete saliva into the oral cavity. 4. Sublingual Caruncles: Small papilla-like structures located on either side of the lingual frenulum. These contain the openings of the submandibular ducts (Wharton’s ducts), which drain saliva from the submandibular gland into the mouth. 3/20/2025 Baasir Umair 47

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