Zygomaticus Major Muscle is the muscle for Facial Expression drawing the angle of mouth superiorly and posteriorly making the Smile. This muscle extends to the corners of mouth from each Zygomatic Arch or Cheekbone.

Zygomaticus Minor Muscle is also a Muscle for Facial Expressions. It originates from the Malar Bone and inserts into the upper part of the upper Lip. Zygomaticus Minor Muscle is often confused With the Zygomaticus Major muscle which inserts into angle of mouth.

INNERVATIONS

Facial Nerves Innervates the Zygomaticus Major Muscle. To be more specific Buccal and Zygomatic branches of the Facial Nerve innervates the muscle. Zygomaticus Minor Muscle is also innervated by the Facial Nerve CN VII.

BLOOD SUPPLY

Both the muscles are supplied blood from the Facial Artery which is the branch of External Carotid Artery also known as Anaesthetist’s Artery.

FUNCTIONS

Zygomaticus Major Muscle actions draw the lips upward and lateral forming a smile. Zygomaticus Minor Muscle is attached at Cheekbone and extends to area between upper lip and nose. It is used in making variety of expressions like Sadness and Discomfort.

CLINICAL SIGNIFICANCE

Inability to form Facial expressions may be the first symptom of the damage of these Facial Muscles- due to diminished nerve supply. Damage to facial nerve causes Facial Paralysis. This type of damage occurs due to:

• Stroke

• Bell’s Palsy

• Parotid Salivary Gland Cancer

• Infectious Myositis

• Myopathy