When making a "smile" expression, facial muscles touch each other, resulting in a depression called "dimple". Some people call it "laughing nest", or because of its different location and size, it is also called "pear nest". Not everyone has dimples, but people who have dimples also have different shapes and heights.
Under subdivision, dimples are located about 2-2.7 cm above the corners of the mouth, and there are three kinds of dimples: round, oval and fissure. Generally, dimples are the most obvious when you laugh. And there is a nest on the face, called pear nest. The pear nest is located below the corner of the mouth, about 1 cm. Pear nests are smaller than dimples, so they are not clear. The formation of dimples is mainly genetic. It can also be obtained through plastic surgery.
Extended data
Causes of dent formation
The Root of Dimple Facial Muscle Defect: Three Muscles
1, zygomatic muscle: Normal zygomatic muscle starts from zygomatic bone and ends at the fusion of levator oris and orbicularis oris muscle, while variant zygomatic muscle has two tendons or is divided into two muscle bundles, which makes it sag. When we smile, the depression takes on the shape of a dimple. Function of zygomatic muscle: It is an important muscle to produce a smile.
2. Smiling muscle: it is a kind of muscle with changeable opposite sex, and many fibers formed by this muscle through the surrounding fascia gather in the corners of the mouth. Once this aggregation forms a point connection with subcutaneous fibers, it will promote the formation of dimples. Smiling muscle function: pull your mouth outward during facial movements, including grinning and laughing.
3, zygomatic minor muscle: from the zygomatic bone, it is often similar to levator labialis and zygomatic major muscle * * *, curling the upper lip and smiling, and expressing contempt, disdain and pride. Another hypothesis: subcutaneous adipose tissue is a fixed point, and the moving force of the surrounding facial muscles is a moving point, thus pulling the skin, making the skin at the fixed point relatively depressed and forming dimples.
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