Muscles of the face

The Muscles of the face, which are also known as craniofacial muscles, are those muscles that are associated with the bones of our head; allow us to move our jaws to chew and have facial expressions, among other things.

The bones of the head belong to the part of our skeleton that we know as axial skeleton, where the bones of the skull, neck, rib cage and spine are classified.

All these bones perform very important functions in the protection of our internal organs, that is: the brain and spinal cord, the heart, the lungs and the rest of the viscera..

The muscles that allow the movement of the different structures of our face are striated skeletal muscles, as they are related to the bones of our head. These are found under the skin of our face and our scalp, between the skin and the bones..

Functions of the muscles of the face

The muscles of the face are striated skeletal muscles, which means that they are composed of elongated muscle cells -muscle fibers- that, seen under the microscope, present a characteristic banding pattern, with interspersing transverse bands, some light and others dark (see more about skeletal muscle).

Unlike other skeletal muscles, the muscles of the face are not covered by a thin layer of connective tissue called fascia and, in addition, these have a more complex pattern of nerve connections than that of most of the muscles in the rest of the body.

These muscles are spatially located "around" facial holes or "openings," such as the eyes, mouth, nose, and ears, and they also stretch through the skull and neck. Many originate in the bones of the skull and spread, inserting into the skin.

There are two main functions of the muscles of the face:

• The chewing and the speaks, critical for initial food processing and communication.
• The development of facial expressions, contributing significantly to social relationships.

The muscles that are responsible for facial expressions, that is, those that allow us to smile and frown, are connected to the central nervous system through facial nerve VII and receive blood from an artery called facial artery.

Muscles of the face

The muscles of the face, depending on their functions, are usually classified into two groups: those of chewing and those of facial expressions..

Chewing muscles

• Temporal muscle: arising in the lateral part of the skull, above the temporal bone.
• Medial pterygoid muscle: connected with the lower jaw bone.
• Lateral pterygoid muscle: originates in the lower portion of the sphenoid bone, in the middle part of the skull base.
• Masseter muscle: it is one of the strongest muscles in the body, it can exert a force of up to 90 kg and it is the muscle that is responsible for raising and closing the jaw.

It must also be said that the buccinator muscle, which belongs to the group of facial muscles of the mouth, also participates in the chewing process as an accessory muscle..

Facial muscles

According to the region to which they belong, they are classified into four groups:

• Mouth muscles

Also known as the muscles of the "bucolabial" group, these muscles are those that control the movements and shape of the mouth and lips..

There are 11 muscles that are responsible for: raising and removing the upper lip, turning it upside down (everting it); depress and evert the lower lip; close the lips and compress the cheeks. These muscles are:

1. Orbicularis muscle of the mouth: "circular" muscle that surrounds the mouth and forms most of the lips.
2. Buccinator muscle: it is the muscular base of the cheeks and fills the space between the maxilla and the mandible.
3. Elevator upper lip muscle.
4. Lower lip depressor muscle.
5. Levator muscle upper lip and wing of nose.
6. Mental muscle (chin): a muscle found in the jaw that has a conical shape.
7. Laughter muscle: there are two muscles, one on each side of the mouth, that extend horizontally to the zygomatic arch.
8. Levator angus muscle: is located on both sides of the nose.
9. Depressor angusis muscle: it is located in the lower area of ​​the mouth, in the jaw, on the sides of the mental muscle.
10. Zygomaticus major muscle.
11. Zygomaticus minor muscle.

These muscles, of course, are in the front of our face, around the lips..

• Muscles of the nose

The muscles of the nose are closely related to the development of facial expressions, but they also play an important role in breathing, as they control the opening of the nostrils. They are two muscles:

1. Nasal muscle: which is divided into two parts, one wing and the other transversal. It is located on both sides of the back of the nose.
2. Hero muscle: it is the muscle connected to the nose that is between the eyes, between the eyebrows, it arises from the nasal bone and from the upper part of the lateral nasal cartilage, it extends in a fan shape towards the lower part of the forehead.

• Eyelid muscles

It is the group of muscles that allows us to open and close our eyes to look, when we sleep, to prevent debris from entering our eyes, etc. It includes the following muscles:

• Orbicularis muscle of the eye: which has three parts, one associated with the ocular orbits, another with the lacrimal ones and another with the eyelids.
• Superciliary muscle (corrugator): it is an elongated muscle; there are two, one above each eye, which are under the eyebrows, up to the final middle part of the same.

• Skull and neck muscles

They are the muscles that allow us to raise our eyebrows, frown or make facial expressions of astonishment. The neck muscles also belong to this group, which participate in the opening of the mouth (through the movement of the jaw) and in the depression movements of the corners of the mouth and the lower lip. These muscles are:

• Occipitofrontal muscle: a large muscle that is located in most of the forehead and the scalp, ending in the eyebrows. It has two parts, one frontal and one occipital.
• Platysma muscle: it is a flat muscle, shaped like a sheet or leaf, which is found in the anterior part of the neck, under the jaw; extends from the jawbone to the shoulders and reaches part of the thorax.

External ear muscles

Also known as auricular muscles, they are a set of thin fan-like muscles that are responsible for connecting the atrium of the ear (where the earrings are worn) with the scalp and allow us to perform certain movements of the atrium. There are three muscles:

• Anterior atrial muscle.
• Posterior atrial muscle.
• Superior atrial muscle.