BDS 1st Year Anatomy: Tongue

Tongue is a muscular organ located on the floor of the mouth, composed entirely of skeletal muscle, allowing voluntary control. It plays a vital role in chewing, speech, swallowing, and taste perception, making its anatomy crucial for BDS 1st-year students.

 Understanding the tongue’s structure, muscles, papillae, blood supply, nerve supply, lymphatic drainage, and clinical significance is essential for exams and practical applications. Check detailed overview, highlighting high-yield concepts, clinical correlations, and exam-focused insights to help students prepare both theory and practical aspects of the tongue in BDS anatomy.

Functions of Tongue

The tongue performs essential roles in oral physiology, including mastication, speech, and swallowing. It also reflects overall health, making it important for clinical diagnosis and examination.

• Mastication: Balances food between teeth and cheeks for effective chewing.

• Speech: Facilitates articulation; size or abnormalities affect clarity.

• Swallowing (Deglutition): Pushes food bolus toward pharynx and esophagus.

• Health Indicator: Tongue appearance can reveal systemic conditions.

Anatomical Features

The tongue’s anatomy includes the dorsum, inferior surface, tip, body, root, and papillae. Detailed knowledge of these features is essential for BDS practical exams and clinical understanding.

Dorsum of the Tongue

The dorsum is the superior surface visible on protrusion. It is divided into anterior and posterior regions by the sulcus terminalis, with papillae concentrated in the anterior portion for taste perception.

• Anterior 2/3 (Oral Part): Contains papillae with taste buds.

• Posterior 1/3 (Pharyngeal Part): Houses palatine tonsils and glossoepiglottic folds.

• Landmarks: Sulcus terminalis, foramen cecum.

Inferior Surface of the Tongue

The inferior surface features structures important for clinical practice, including salivary gland openings, deep lingual veins, and the lingual frenum.

• Lingual Frenum: Connects tongue to floor of mouth.

• Salivary Duct Openings: Submandibular and sublingual.

• Deep Lingual Veins: Key for sublingual drug absorption.

• Plica Fimbriata: Mucosal fold on lateral aspect.

Papillae of Tongue

Papillae are projections responsible for taste perception. Understanding their types, locations, and functions is essential for exams and clinical application.

• Circumvallate: Large, 8–12 in number, located near sulcus terminalis, contain taste buds.

• Fungiform: Scattered, pedunculated, contain taste buds.

• Filiform: Conical, no taste buds, prone to pathology.

• Foliate: Leaf-shaped, lateral borders, contain taste buds.

Muscles of Tongue

Tongue muscles are classified as intrinsic and extrinsic. Intrinsic muscles change the tongue’s shape, while extrinsic muscles control its movement. These are frequently examined in practical and theory exams.

Intrinsic Muscles

Intrinsic muscles originate and insert within the tongue, altering its shape for precise movements.

• Superior Longitudinal: Shortens tongue, dorsum concave.

• Inferior Longitudinal: Shortens tongue.

• Transverse: Narrows and elongates tongue.

• Vertical: Broadens and flattens tongue.

Extrinsic Muscles

Extrinsic muscles originate externally and control tongue positioning.

• Genioglossus: Protrudes tongue; “safety muscle” preventing airway blockage.

• Hyoglossus: Depresses tongue.

• Styloglossus: Retracts tongue.

• Palatoglossus: Elevates tongue.

Blood Supply and Venous Drainage

The tongue receives arterial blood mainly from the lingual artery and drains via deep and dorsal lingual veins. Understanding vascular supply is critical for surgical and clinical applications.

• Arterial Supply: Lingual artery (main), tonsillar, and ascending pharyngeal contributions.

• Venous Drainage: Deep lingual and dorsal lingual veins to internal jugular vein.

Nerve Supply

Motor and sensory innervation of the tongue is crucial for function and clinical diagnosis.

• Motor: Hypoglossal nerve (CN XII) for all muscles except palatoglossus (Vagus CN X).

• Sensory:

• Anterior 2/3: Lingual nerve (general), Chorda Tympani (taste)

• Posterior 1/3: Glossopharyngeal (CN IX)

• Posterior-most: Vagus (CN X)

Lymphatic Drainage

The tongue’s lymphatics drain different regions into specific nodes, important for oral cancer and infection evaluation.

• Tip: Submental nodes

• Anterior 2/3: Submandibular nodes

• Posterior 1/3: Deep cervical nodes including jugulo-omohyoid nodes

Clinical Significance

Clinical conditions associated with the tongue are commonly tested in exams and relevant for patient care.

• Hypoglossal Nerve Palsy: Tongue deviates toward the affected side.

• Geographic Tongue: Map-like lesions on the dorsum.

• Ankyloglossia (Tongue Tie): Restricts movement; may require surgery.

• Tongue Carcinoma: Common site for oral cancer.