There is a third layer of muscle in the human masseter muscle: modern anatomy textbooks say that the masseter muscle has only two layers

In recent years, many female netizens have heatedly discussed a kind of topic: how to make the masseter muscles naturally smaller? How to get the masseter muscles to disappear quickly? Elimination of the masseter muscle method ... A recent study helped to help people understand this muscle better.

According to the Recent Report of the American Fun Science Website, Swiss scientists recently discovered a human body part that has never been described before - a layer of muscle located inside the masseter muscle. This latest finding could help in the treatment of related diseases such as the jaw.

Modern anatomy textbooks say that the masseter muscle has two layers: one deep and one shallow. But some historical documents also suggest that there may be a third layer of the masseter muscle, but there are so many opinions about its location that the authors involved in the latest study decided to examine whether there is still a layer hidden in the protruding mandibular muscle.

To do so, they dissected 12 human heads kept in formaldehyde, performed CT scans of another 16 "fresh" corpses, and performed MRI scans on one volunteer. Through these examinations, they identified a third layer of the masseter muscle: this layer extends from the zygomatic process (a bone-like protrusion that forms part of the "cheekbones" and other bones are connected to the cheekbones) to the coronary process (a protrusion on the mandible).

Sylvia Mezi, lead author of the study and senior lecturer in the Department of Biomedicine at the University of Bern, notes: "This deep part of the masseter muscle functions significantly differently from the other two layers, and depending on the arrangement of its muscle fibers, this layer of muscle may help stabilize the lower jaw by 'lifting and contracting' the coronary process." In fact, the newly discovered muscle layer is the only part of the masseter muscle that is able to pull the jaw backwards. ”

In a paper published online in the Annals of Anatomy, the team suggested naming the newly discovered muscle layer "masseter coronous muscle," meaning "the coronal part of the masseter muscle."

Now, do you have a new understanding of the masseter muscles? (Science and Technology Daily, Zeta)

Source: Daily Economic News