Facial muscles (overview)

The facial muscles are a group of relatively thin and flat skeletal muscles located beneath the skin within the subcutaneous tissue of the face and scalp. They are primarily responsible for facial expressions. These muscles are also known as the muscles of facial expression or mimetic muscles because they control movements of the overlying facial skin, enabling expressions such as smiling and frowning.

Most facial muscles originate from bones of the facial skeleton (viscerocranium). Their fibers radiate to insert into the skin, which makes them unique among skeletal muscles. However, some also connect with each other to form muscle complexes.

These muscles are mainly grouped around the natural orifices of the face, such as the eyes, nose, and mouth, where they function in opening and closing these structures. Based on their anatomical location, they are categorized into several groups.

• Muscles of the scalp
  • Occipitofrontalis muscle (Read more!)
    • Frontalis muscle (frontal belly of occipitofrontalis) (Read more!)
    • Occipitalis muscle (occipital belly of occipitofrontalis) (Read more!)
• Muscles around the orbital opening
  • Corrugator supercilii (Read more!)
  • Depressor supercilii (Read more!)
  • Orbicularis oculi (Read more!)
  • Procerus (Read more!)
• Muscles around the nasal opening
  • Procerus
  • Nasalis (Read more!)
    • Transverse nasalis (transverse part of nasalis) (Read more!)
    • Alar nasalis (alar part of nasalis) (Read more!)
  • Dilator naris anterior (Read more!)
  • Compressor narium minor (Read more!)
  • Depressor septi nasi (Read more!)
  • Levator labii superioris alaeque nasi (Read more!)
• Muscles around the oral opening
  • Orbicularis oris (Read more!)
  • Levator labii superioris alaeque nasi
  • Levator labii superioris (Read more!)
  • Levator anguli oris (Read more!)
  • Zygomaticus minor (Read more!)
  • Zygomaticus major (Read more!)
  • Risorius (Read more!)
  • Buccinator (Read more!)
  • Depressor anguli oris (Read more!)
  • Depressor labii inferioris (Read more!)
  • Mentalis (Read more!)

Unlike other skeletal muscles, facial muscles do not have fascia, except for the buccinator. They are all supplied by branches of the facial artery and innervated by the branches of the facial nerve (CN VII). Additionally, they have a higher concentration of fast-twitch fibers and fewer mitochondria than other skeletal muscles. Notably, the orbicularis oculi is the fastest-moving muscle in the human body.

Note: There are also three muscles around the ear (extrinsic auricular muscles) - anterior auricular muscle, posterior auricular muscle, and superior auricular muscle. These muscles are generally considered insignificant in human anatomy, so they are not covered in detail in this article.