Shape of tongue

 Shape of tongue mainly includes several changes as follows :

Rough tongue and tender tongue: Rough tongue is marked by rough or curved texture, dry surface and dull colour; while tender tongue is characterized by fine texture, moistened and lustrous surface, light colour and bulgy appearance.

Inspecting to see whether the tongue is rough or tender is helpful for understanding whether the disease is of asthenia or sthenia. Rough tongue usually indicates sthenia syndrome and heat syndrome due to hyperactivity of yank-heat and consumption of body fluid. Tender tongue usually signifies asthenia syndrome and cold syndrome due to failure of asthenia yang to transport dampness, or due to qi asthenia and deficiency of yin-essence, which fail to nourish the tongue.

Bulgy tongue. The tongue is bigger than usual (see colour Fig. 6 ), usually indicating internal retention of dampness and phlegm.
 
Bulgy tongue is caused either by qi ast, henia or yang asthenia which fail to warm and transform fluid, leading to stagnation of fluid or accumulation of dampness into phlegm in the tongue collaterals. Light-white and bulgy tongue with moist and slippery fur is due to asthenia of spleen and kidney yang which fails to transform body fluid and leads to internal retention of dampness and phlegm. Light-red or red and bulgy tongue with yellowish greasy fur is usually due to damp-heat in the spleen and stomach.

Swollen tongue. Swollen tongue means that the tongue is swollen, usually suggesting sthenia syndrome.

Swollen tongue is either caused by superabundant heat in the heart and spleen, or by mixture of febrile pathogenic factors with alcoholic toxin attacking on the upper, or by intoxication which leads to stagnation of qi and blood in the tongue collaterals. Deep-red and swollen tongue is due to superabundant heat in the heart and spleen. Purplish, dull and swollen tongue is due to alcoholism or intoxication.

Thin and emaciated tongue. The tongue is thinner than usual (see colour Fig. 7), indicating asthenia of qi and blood or consumption of yin fluid.
 
Thin tongue is usually due to asthenia of qi and blood, or consumption of yin fluid and insufficient moisture and nutrition of the tongue. Light-coloured and thin usually signifies asthenia syndrome and cold syndrome due to failure of asthenia yang to transport dampness, or due to qi asthenia and deficiency of yin-essence, which fail to nourish the tongue.

Bulgy tongue. The tongue is bigger than usual (see colour Fig. 6 ), usually indicating internal retention of dampness and phlegm.

Bulgy tongue is caused either by qi ast, henia or yang asthenia which fail to warm and transform fluid, leading to stagnation of fluid or accumulation of dampness into phlegm in the tongue collaterals. Light-white and bulgy tongue with moist and slippery fur is due to asthenia of spleen and kidney yang which fails to transform body fluid and leads to internal retention of dampness and phlegm.Light-red or red and bulgy tongue with yellowish greasy fur is usually due to damp-heat in the spleen and stomach.

Swollen tongue. Swollen tongue means that the tongue is swollen, usually suggesting sthenia syndrome.

Swollen tongue is either caused by superabundant heat in the heart and spleen, or by mixture of febrile pathogenic factors with alcoholic toxin attacking on the upper, or by intoxication which leads to stagnation of qi and blood in the tongue collaterals. Deep-red and swollen tongue is due to superabundant heat in the heart and spleen. Purplish, dull and swollen tongue is due to alcoholism or intoxication.

 Thin and emaciated tongue. The tongue is thinner than usual (see colour Fig. 7), indicating asthenia of qi and blood or consumption of yin fluid.

Thin tongue is usually due to asthenia of qi and blood, or consumption of yin fluid and insufficient moisture and nutrition of the tongue. Light-coloured and thin  tongue is caused by deficiency of qi and blood; deep-red  and thin tongue is caused by exuberant heat consuming yin  or by superabundance of fire due to yin asthenia.
 
Fissured tongue. There are various fissures on the  tongue (see colour Fig. 8), indicating deficiency of fluid  or essence and blood.
 
Fissured tongue is usually due to consumption of body fluid or asthenia of essence and blood. Deep-red and fissured tongue is due to exuberant heat consuming fluid; light-coloured and fissured tongue is due to asthenia of essence and blood.
 
However, fissured tongue may be seen in some healthy people, known as congenital fissured tongue. Such a tongue is marked by
fine fissures and covered with tongue fur.

Prickly tongue. The tongue is covered with reddish  prickles (see colour Fig. 9), suggesting superabundance of pathogenic heat.

Prickly tongue is due to superabundance of heat in the viscera, invasion of heat into blood and accumulation of heat in the tongue collaterals. The location of prickles may indicate the location of pathogenic heat. Prickles on the tongue tip indicate hyperactivity of heart fire; prickles on the tongue center indicate superabundance of heat in the stomach and intestines; prickles on the margins indicate exuberance of liver and gallbladder fire. The more the prickles and the deeper the colour, the severer the pathogenic heat.

Tooth-marked tongue. The margins of the tongue are printed with tooth marks (see colour Fig. 10), indicating qi asthenia or yang asthenia and internal retention of dampness.
 
The spleen governs transportation and transformation. The decline of the spleen qi or spleen yang will lead  to dysfunction in transportation and transformation as well as internal retention of dampness in the tongue, resulting  in bulgy tongue which is squeezed by teeth. That is why  tooth-marked tongue and bulgy tongue appear simultaneously.

However, tooth-marked tongue is also seen among some healthy people, characterized by constant existence of slight tooth-marks and no bulging manifestation.