Also known as the fraenum or frenulum, this comprises the folds of mucous membrane that anchor the bottom of the tongue to the ?oor of the mouth.
Structure The substance of the tongue consists almost entirely of muscles running in various directions. The tongue also has numerous outside attachments: one muscle on each side unites it to the lower jaw-bone just behind the chin, and this muscle serves to protrude the tongue from the mouth; other muscles, which retract the tongue, attach it to the hyoid bone, the larynx, the PALATE, and the styloid process on the base of the SKULL.
The mucous membrane on the undersurface of the tongue is very thin. In the middle line, a fold of mucous membrane, the frenum, passes from the under-surface to the ?oor of the mouth; when this frenum is attached too far forwards towards the tip of the tongue, the movements of the organ are impeded – the condition being known as tongue-tie. On the upper surface or dorsum of the tongue, the mucous membrane is thicker, and in its front two-thirds is studded with projections or papillae, most of which are conical. Some of them end in long ?laments, and are then known as ?liform papillae. On the tip, and towards the edges of the tongue, small, red, rounded fungiform papillae are seen, which act as end-organs for the sense of taste – as do circumvallate papillae, each of which is surrounded by a trench along which open numerous taste-buds. These taste-buds are also found in the fungiform papillae, scattered over
the throat, FAUCES, and palate. Five nerves, originating from the ?fth, seventh, ninth, tenth and 12th cervical nerves supply the tongue.... tongue
Ankyloglossia or tongue-tie is a rare disorder in which the frenum or band connecting the lower surface of the tongue to the ?oor of the mouth is so short or tight that the tongue cannot be protruded. Surgery can remedy the defect. It is easy to overdiagnose and is not a common cause of di?culty in feeding at birth or speech defects in infancy.
Gross enlargement of the tongue can make speech indistinct or make swallowing and even breathing di?cult. This is known as macroglossia and may be such that the tongue is constantly protruded from the mouth. The cause may be CONGENITAL, as in severe cases of DOWN’S (DOWN) SYNDROME, or it may occur as a result of ACROMEGALY or be due to abnormal deposits as in AMYLOIDOSIS.
A marked tremor of the tongue when protruded may be seen in various neurological diseases, but may be caused by alcoholism.
After a STROKE involving the motor nerve centre, the control of one side of the tongue musculature will be lost. This will result in the protruded tongue pointing to the side of the body which is paralysed. The sense of taste on one side of the tongue may also be lost in some diseases of the brain and facial nerve.
The presence of fur on the tongue may be obvious and distressing. This is due to thickening of the super?cial layers of the tongue which may appear like hairs which trap food debris and become discoloured. Furring is common during fever and as a result of mouth-breathing and smoking.
In some conditions the tongue may appear dry, red and raw (GLOSSITIS). An in?amed beefy tongue is characteristic of pellagra, a disease caused by de?ciency of NICOTINIC ACID in the diet. A magenta-coloured tongue may be seen when there is a lack of RIBOFLAVIN.
Ulcers of the tongue are similar to those elsewhere in the mouth. The most common are aphthous ulcers which are small, red and painful and last for about ten days. They are associated with stress, mild trauma (such as from jagged teeth), and occasionally with folic acid and vitamin B12 de?ciency. Ulcers of the tongue are sometimes found in patients with chronic bowel disease.... tongue, disorders of
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