Tongue is the organ of human body to taste food, and the feeling of tongue is called "taste", which is in human mouth. In traditional Chinese medicine, tongue is also called spiritual root and mind. The tip of the tongue is called the tip of the tongue, the middle is called the tongue, the root is called the tongue, and both sides are called the lingual side.
There is a V-shaped groove at the top of the tongue, called the boundary groove, which divides the tongue into the front 2/3 of the tongue body and the back 1/3 of the tongue base. The front of the tongue is called the tip of the tongue. There is a mucosal fold in the middle of the sublingual part, which is called lingual frenulum.
There are a pair of small protrusions on both sides of the root of lingual frenulum, which are called hypoglossal caruncle. At the top of the caruncle, there are the same openings of submandibular gland duct and sublingual gland duct. The mucosal protuberance extending from the hypoglossal nerve caruncle to the posterolateral side is called hypoglossal nerve fold, and the sublingual gland is hidden on the deep surface of this fold.
Each taste bud consists of several taste cells, which extend out of the taste bud pores through the cilia at the top and feel the taste of chemicals dissolved in water. Solid or gaseous substances must also be dissolved in saliva in order for taste buds to taste. The terminal of taste cells is connected with the entrance nerve. When the taste cells are excited, the impulse is introduced into the taste center of the brain along the afferent nerve, resulting in taste.
Clinical common tongue diseases:
Dry tongue: mild dryness, no appearance change; Apparent dryness is seen in nasal diseases (which may be accompanied by mouth breathing and lack of saliva), heavy smoking, atropine effect, and after radiotherapy. Severe dryness of the tongue can be seen as atrophy of the tongue with longitudinal grooves, and severe dehydration can be seen, which may be accompanied by decreased skin elasticity.
Enlargement of tongue body: temporary enlargement is seen in glossitis, stomatitis, cellulitis of tongue body, abscess, hematoma, angioneurotic edema, etc. Long-term increase is seen in myxedema, dementia, tongue tumor and so on.
Hairy tongue: also known as black tongue, the surface of the tongue is covered with black or yellowish brown hair, so it is called hairy tongue, which is made up of filamentous papillae wrapped around true hyphae and keratinized epithelial cells. It is seen in patients with long-term illness or long-term use of broad-spectrum antibiotics leading to fungal growth.