ANATOMY OF TONGUE presentation otorhinolaryngology

1. Introduction
The tongue is a highly specialized muscular organ located within the oral cavity, functioning as an essential component of the digestive and speech systems. It plays a pivotal role in mastication, swallowing (deglutition), taste perception, articulation, and oral hygiene. Anatomically, the tongue is a complex structure composed of skeletal muscles, connective tissue, mucous membranes, glands, blood vessels, and nerves. Its unique architecture allows for remarkable flexibility and precision of movement.
The study of the tongue’s anatomy encompasses multiple disciplines: gross anatomy, which explores its external and internal structures; histology, which examines microscopic organization; and neurovascular anatomy, which explains its innervation and blood supply. Understanding these components provides crucial insight into both normal function and the pathophysiology of tongue-related disorders.
2. Gross Anatomy
2.1. Location and Extent
The tongue occupies most of the oral cavity’s floor. It extends from its anterior free tip, lying just behind the incisors, to its posterior attachment at the oropharynx. Approximately two-thirds of its total mass lies within the oral cavity (oral or anterior part), while the posterior one-third lies in the oropharynx (pharyngeal part).
The tongue rests on the mylohyoid muscle, which forms the muscular diaphragm of the floor of the mouth. Its root is anchored to surrounding structures — the mandible, hyoid bone, and styloid process — by extrinsic muscles and connective tissue.
2.2. Surfaces and Parts
The tongue is divided anatomically into:
Apex (tip) — the anterior, mobile portion.
Body — the central part extending from the apex to the sulcus terminalis.
Root (base) — the posterior fixed portion attached to the hyoid bone and mandible.
Inferior surface — smooth, connected to the floor of the mouth by the lingual frenulum.
2.3. Dorsum of the Tongue
The dorsal surface of the tongue is covered with specialized mucosa and is divided into two regions by a V-shaped groove known as the sulcus terminalis. The apex of this V points posteriorly toward the foramen cecum, a small pit that marks the embryological site of the thyroglossal duct.
Anterior two-thirds (oral part) — lies in the oral cavity, covered by non-keratinized stratified squamous epithelium with various papillae.
Posterior one-third (pharyngeal part) — faces the oropharynx and is covered by non-keratinized epithelium containing numerous lingual lymphoid follicles, collectively forming the lingual tonsil.
2.4. Papillae of the Tongue
The anterior two-thirds of the dorsum display four distinct types of papillae, which serve mechanical and gustatory functions.
1. Filiform Papillae
Most numerous, slender, and conical.
Distributed across the entire anterior dorsum.
Covered by keratinized epithelium, giving the tongue a rough texture.
Primarily mechanical in function; do not contain taste buds.
2. Fungiform Papillae
Scattered among filiform papillae,

1. ANATOMY OF TONGUE MODERATOR – DR. DEEKSHITH SHETTY. PRESENTER – DR. ALOYSIUS REUBEN.

2. EMBRYOLOGY THE TONGUE APPEARS IN THE EMBRYOS AT APPROXIMATELY 4 WEEKS IN THE FORM 2 LATERAL SWELLINGS AND 1 MEDIAN SWELLING , THE TUBERCULAR IMPAR

3. THESE 3 SWELLINGS ORIGINATE FROM THE FIRST PHARYNGEAL ARCH. AS THE LATERAL SWELLINS INCREASE IN SIZE, THEY OVERGROW THE TUBERCULUM IMPAR AND MERGE, FORMING THE ANTERIOR 2/3 OR THE BODY OF THE TONGUE. SINCE THE MUCOSA COVERING THE BODY OF THE TONGUE ORIGINATES FROM THE 1 ST PHARYNGEAL ARCH, THE SENSORY INNERVATION OF THIS AREA IS BY THE MANDIBULAR BRANCH OF THE TRIGEMMINAL NERVE.

4. THE BODY OF THE TONGUE IS SEPERATED FROM THE POSTERIOR PART BY A V- SHAPED GROOVE CALLED THE SULCUS TERMINALIS THE POSTERIOR PART OR THE ROOT, OF THE TONGUE IS DERIVATED FROM THE 2 ND , 3 RD AND THE PARTS OF 4 TH PHARYNGEAL ARCH. THE SENSORY INNERVATION IS BY THE GLOSSOPHARYNGEAL NERVE .

5. ANATOMY THE TONGUE IS A MOBILE MUSCULAR ORGAN IN THE ORAL CAVITY, WHICH BULGES UPWARDS FROM THR FLOOR OF THE MOUTH & ITS POSTERIOR PART FORMS THE ANTERIOR WALL OF THE OROPHARYNX. FUNCTIONS : TASTE, SPEECH, MASTICATION & DEGLUTITION (ORAL PHASE). SHAPE : CONICAL IN SHAPE BEING ELONGATED POSTERO-ANTERIORLY & FLATTENED DORSO-VENTRALLY. EXTERNAL FEATURES : A ROOT, TIP & BODY.

6. ROOT : THE ROOT OF THE TONGUE IS ATTACHED TO THE MANDIBLE & HYOID BONE BY MUSCLES. THE NERVE & VESSELS OF THE TONGUE ENTER THROUGH ITS ROOT. TIP : IT IS THE ANTERIOR FREE END , WHICH COMES IN CONTACT WITH THE CENTRAL INCISORS. BODY : THE BULK OF THE TONGUE BETWEEN THE ROOT & THE TIP IS CALLED BODY. IT HAS DORSAL & VENTRAL SURFACES. RIGHT & LEFT LATERAL MARGINS.

7. DORSAL SURFACE : IT IS DIVIDED INTO 2 PARTS BY A V-SHAPED SULCUS, THE SULCUS TERMINALIS. ANTERIOR 2/3 RD OR ORAL PART. POSTERIOR 1/3 RD OR PHARYNGEAL PART. THE APEX OF THE SULCUS TERMINALIS IS MARKED BY A BLIND FORAMEN, THE FORAMEN CAECUM , WHICH INDICATES THE POINT OF ORIGIN OF THE MEDIAN THYROID DIVERTICULUM (THYROGLOSSAL DUCT).

8. ORAL PART: A MEDIAN FURROW, REPRESENTING BILATERAL ORIGIN OF THE TONGUE. LARGE NUMBER OF PAPILLAE PHARYNGEAL PART: A LARGE NUMBER OF LYMPHOID FOLLICLES, WHICH TOGETHER CONSTITUTE THE LINGUAL TONSIL. A LARGE NUMBER OF MUCOUS AND SEROUS GLANDS.

9. PAPILLAE OF THE TONGUE. VALLATE PAPILLAE : FORMERLY KNOWN AS CIRCUMVALLATE PAPILLAE. THEY ARE THE LARGEST AND ARE ARRANGED IN V-SHAPED ROW IN FRONT OF SULCUS TERMINALIS. FILIFORM PAPILLAE : THESE ARE NARROWEST & MOST NUMEROUS. THEY ARE LOCATED ABUNDANTLY ON THE DORSUM OF THE TONGUE. THEY DO NOT BEAR TASTE BUDS. FUNGIFORM PAPILLAE : THEY ARE MOSTLY PRESENT AT THE APEX & MARGINS OF THE TONGUE.

10. FOLIATE PAPILLAE : THEY ARE PRESENT NEAR THE MARGIN IN FRONT OF SULCUS TERMINALIS. THEY ARE RUDIMENTARY IN HUMANS.

11. VENTRAL SURFACE – IT PRESENTS THE FOLLOWING FEATURES FRENULUM LINGUAE – MEDIAN FOLD OF MUCOUS MEMBRANE CONNECTING THE TONGUE TO THE FLOOR OF MOUTH. DEEP LINGUAL VEIN – MAY BE SEEN ON EITHER SIDE OF THE FRENULUM. THE LINGUAL NERVE & LINGUAL ARTERY ARE MEDIAL TO THE VEIN BUT NOT VISIBLE. PLICA FIMBRIATA – A FRINGED FIMBRIATED FOLD OF MUCOUS MEMBRANE LATERAL TO THE LINGUAL VEIN.

12. TONGUE TIE (ANKYLOGLOSSIA): IF FRENULUM EXTENDS TOO FAR TOWARD THE TIP OF THE TONGUE, IT IS CALLED TONGUE TIE. IT INHIBITS NORMAL MOVEMENTS OF THE TONGUE & MAY INTERFERE WITH NORMAL SPEECH. THIS CAN BE CORRECTED BY CUTTING THE FRENULUM SURGICALLY.

13. MUSCLES OF THE TONGUE THE MUSCULATURE OF TONGUE CONSISTS OF EXTRINSIC & INTRINSIC MUSCLES. THE INTRINSIC MUSCLES ARE WITHIN THE TONGUE & HAVE NO ATTACHMENT OUTSIDE THE TONGUE. WHEREAS EXTRINSIC MUSCLES TAKE ORIGIN FROM STRUCTURES OUTSIDE THE TONGUE & ENTER THE TONGUE TO BE INSERTED IN IT. THE INTRINSIC MUSCLES CHANGE THE SHAPE OF THE TONGUE WHEREAS EXTRINSIC MUSCLES MOVE THE TONGUE.

14. INTRINSIC MUSCLES: SUPERIOR LONGITUDINAL. INFERIOR LONGITUDINAL TRANSVERSE VERTICAL

15. EXTRINSIC MUSCLES: GENIOGLOSSUS HYOGLOSSUS STYLOGLOSSUS PALATOGLOSSUS

16. SAFETY MUSCLE OF THE TONGUE – GENIOGLOSSUS THEY ARE CALLED BECAUSE 2 GENIOGLOSSUS FORM THE BULK OF THE TONGUE AND ARE RESPONSIBLE FOR THE PROTRUSION OF THE TONGUE. IF THESE MUSCLES PARALYSE, THE TONGUE WILL FALL BACK INTO THE OROPHARYNX & OBSTRUCT THE AIR PASSAGE CAUSING CHOKING & DEATH.

17. ARTERIAL SUPPLY BRANCHES OF LINGUAL ARTERY ; DEEP LINGUAL ARTERIES TO THE ANTERIOR PART & DORSAL LINGUAL ARTERIES TO THE POSTERIOR PART. TONSILLAR BRANCH OF THE FACIAL ARTERY . ASCENDING PHARYNGEAL ARTERY .

18. VENOUS DRAINAGE DEEP LINGUAL VEIN – PRINCIPLE VEIN OF THE TONGUE AND IS VISIBLE ON THE INFERIOR SURFACE OF THE TONGUE. VENAE COMITANTES – ACCOMPANYING THE LINGUAL ARTERY. VENAE COMITANTES – ACCOMPANYING THE HYPOGLOSSAL NERVE. THESE VEINS UNITE AT THE POSTERIOR BORDER OF THE HYOGLOSSUS TO FORM THE LINGUAL VEIN , WHICH DRAINS INTO EITHER COMMON FACIAL OR THE INTERNAL JUGULAR VEIN .

19. LYMPHATIC DRAINAGE APICAL VESSELS (TIP & INFERIOR SURFACE OF THE TONGUE). MARGINAL VESSELS (MARGINAL PORTIONS OF THE ANTERIOR 2/3 RD OF THE TONGUE). CENTRAL VESSELS (CENTRAL PORTION OF THE ANTERIOR 2/3 RD OF THE TONGUE). BASAL VESSELS (ROOT OF THE TONGUE & POSTERIOR 1/3 RD ).

20. PROGNOSIS OF TONGUE CANCER: THERE IS RICH ANASTAMOSIS ACROSS THE MIDLINE BETWEEN THE LYMPHATICS OF THE POSTERIOR 1/3 RD OF THE TONGUE. THEREFORE, A CANCER ON ONE SIDE READILY METASTASISZES TO IPSILATERAL AS WELL AS CONTRALATERAL LYMPH NODES. IN CONTRAST, THERE IS LITTLE CROSS COMMUNICATION OF LYMPHATICS OF THE ANTERIOR 2/3 RD OF THE TONGUE

21. FOR THIS REASON, CANCER IN THE POSTERIOR 1/3 RD OF THE TONGUE HAS POOR PROGNOSIS.

22. NERVE SUPPLY MOTOR SUPPLY : ALL THE MUSCLES OF THE TONGUE (INTRINSIC & EXTRINSIC) ARE SUPPLIED BY THE HYPOGLOSSAL NERVE EXCEPT PALATOGLOSSUS WHICH IS SUPPLIED BY CRANIAL ROOT OF ACCESSORY VIA VAGUS NERVE . SENSORY SUPPLY : ANTERIOR 2/3 RD OF THE TONGUE IS SUPPLIED BY LINGUAL NERVE CARRYING GENERAL SENSATIONS. CHORDA TYMPANI CARRYING SPECIAL SENSATIONS

23. POSTERIOR 1/3 RD : GLOSSOPHARYNGEAL NERVE, CARRYING BOTH GENERAL & SPECIAL SENSATION OF TASTE. BASE OF TONGUE – SUPPLIED BY THE INTERNAL LARYNGEAL NERVE BR. OF SUPERIOR LARYNGEAL NERVE CARRYING SPECIAL SENSATIONS OF TASTE.

24. CARCINOMA OF THE TONGUE – THE TONGUE IS A COMMON SITE FOR CA. IT MOSTLY INVOLVES LATERAL MARGINS OF THE ANTERIOR 2/3 RD OF THE TONGUE THE RELATIVE FREQUENCY ARE : ANTERIOR 2/3 RD - 64%. POSTERIOR 1/3 RD – 20%. POSTERIOR MOST – 6%.

25. MACROGLOSSIA AN ABNORMAL ENLARGEMENT OF TONGUE THAT CAN INTERFERE WITH SPEECH, CHEWING, SWALLOWING & BREATHING. CONGENITAL – DOWNS SYNDROME, BEKWITH-WIEDEMANN SYNDROME, CRETINISM. ACQUIRED – AMYLODOSIS, ACROMEGALY

26. MICROGLOSSIA A DEVELOPMENT ANOMALY WHERE THE TONGUE IS SMALLER THAN NORMAL. OCCURS IN SYNDROMES SUCH AS ‘ OROMANDIBULAR LIMB HYPOGENESIS SYNDROME ’ & ‘ HANHART SYNDROME ’.

27. LINGUAL THYROID IT IS A RARE CONGENITAL ANOMALY WHERE THE THYROID TISSUE IS LOCATED AT THE BASE OF THE TONGUE. THE GLAND FAILS TO DESCEND TO ITS NORMAL PRETRACHEAL POSITION IT IS THE MOST COMMON SITE FOR ECTOPIC THYROID.

28. MISCELLANEOUS LESIONS: MEDIAN RHOMBOID GLOSSITIS: IT IS RED RHOMBOID AREA, DEVOID OF PAPILLAE ON THE DORSUM OF THE TONGUE. IT IS A DEVELOPMENT ANAMOLY THAT OCCURS DUE TO PERSISTENCE OF TUBERCULUM IMPAR. IT IS ASYMPTOMATIC & NO TREATMENT IS NECESSARY.

29. GEOGRAPHICAL TONGUE: IT IS CHARACTERISED BY ERYTHEMATOUS AREA, DEVOID OF PAPILLAE, SORROUNDED BY AN IRREGULAR KERATOTIC WHITE OUTLINE. THE LESION KEEP CHANGING THEIR SHAPE, HENCE IT IS ALSO CALLED AS ‘MIGRATORY GLOSSITIS. IT IS ASYMPTOMATIC & MAY NOT REQUIRE ANY TREATMENT.

30. HAIRY TONGUE DUE TO EXCESSIVE FORMATION OF KERATIN, THE FILIFORM PAPILLAE ON THE DORSUM OF THE TONGUE GET ELONGATED, COLOURED (BLACK OR BROWN) DUE TO CHROMOGENIC BACTERIA & LOOK LIKE HAIR. SMOKING IS ONE OF THE FACTORS. TREATMENT CONSISTS OF SCRAPPING & IMPROVING THE GENERAL NUTRITION OF THE PATIENT.

31. FISSURED TONGUE: IT CAN BE CONGENITAL OR SEEN IN CASES OF SYPHILIS, DEFICIENCY OF VITAMIN B COMPLEX OR ANEMIA. CONGENITAL FISSURING ASSOCIATED FACIAL PALSY IS SEEN IN MELKERSON-ROSENTHAL SYNDROME.

32. TASTE PATHWAY

33. REFERENCES EMBRYOLOGY – LANGMAN’S. ANATOMY – VISHRAM SINGH. ENT – SCOTT BROWNS & CUMMINGS.

34. THANK YOU