Facial muscles

The facial muscles are a unique group of muscles that do not move bones, but move the skin. At one end they are attached to the bones of the skull, at the other they are woven into the skin or mucous membrane. This is why we can smile, frown, raise our eyebrows in surprise and express dozens of other emotions.

Features of facial muscles

• Have no fascia (unlike most skeletal muscles)
• Located superficially - directly under the skin
• Grouped around holes - eyes, mouth, nose, ears
• All are innervated by the facial nerve (VII) - the only nerve for the entire group

Muscles of the cranial vault

The epicranial muscle (m. epicranius) consists of the frontal and occipital bellies, connected by a tendon helmet (aponeurosis). The frontal abdomen raises the eyebrows and forms horizontal wrinkles on the forehead - “facial expressions of surprise.”

Muscle that wrinkles the eyebrow (m. corrugator supercilii) - moves the eyebrows to the midline, creating vertical folds between the eyebrows. This is the muscle of “concentration and anger” - one of the main targets for botulinum toxin injections.

Muscles of the eye area

Orbicularis oculi muscle (m. orbicularis oculi) consists of three parts:

• Century - provides blinking
• Orbital - squinting
• Lacrimal - promotes the outflow of tear fluid

This muscle works up to 20,000 times a day at normal blink rates.

Muscles of the mouth

There is a complex system of muscles around the mouth:

• Orbicularis oris muscle - compresses and extends lips
• Muscle that raises the upper lip - grin, opening of teeth
• Zygomaticus major and minor - form a smile, pull the corner of the mouth upward and laterally
• Muscle of laughter (m. risorius) - stretches the mouth when smiling
• Muscle that lowers the lower lip - expression of sadness
• mentalis muscle - protrudes the lower lip, creates a dimple on the chin

Buccal muscle

Buccal muscle (m. buccinator) deserves special attention. It forms the side wall of the mouth and performs a dual function: when chewing, it presses food against the teeth, and is also involved in whistling and playing wind instruments. In infants, it is the cheek muscle that provides the act of sucking.

Application in medicine and cosmetology

Cosmetologists work with facial muscles every day. Botulinum therapy is based on a temporary blockade of neuromuscular transmission: botulinum toxin prevents the muscle from contracting and the wrinkle is smoothed out. For safe injections, it is necessary to know exactly the location of each muscle, its depth and the direction of the fibers.

When the facial nerve is paralyzed, all facial muscles on one side stop working. This is an emergency condition that requires immediate diagnosis: paralysis can be caused by either a viral infection (Bell's palsy) or a stroke.

You can view the location and direction of the fibers of each facial muscle in 3D anatomical atlas Humio - this is especially useful when preparing for practical classes.