Levator labii superioris

The levator labii superioris is a facial expression muscle that elevates the upper lip. It lies in the midface region, between the infraorbital margin and the upper lip.

Anatomical characteristics

1. Origin

From the infraorbital margin of the maxilla, just above the infraorbital foramen.

2. Insertion

The fibres of levator labii superioris pass downward and medially to insert Into the skin and also blend with the muscle fibres of the orbicularis oris muscle in the upper lip.

Innervation

• Buccal branch of facial nerve

• Zygomatic branch of facial nerve

Blood supply

• Facial artery (superior labial branch)

• Maxillary artery (infraorbital branch)

Action

Works synergistically with other muscles such as the levator labii superioris alaeque nasi, to elevates the upper lip. It also deepens the nasolabial fold.

• Mnemonic Tip: “Levator labii lifts the lip” — remember its name and function both start with L (Levator–Lip).

Clinical correlation

In facial nerve palsy, weakness or paralysis of this muscle contributes to flattening of the nasolabial fold and inability to elevate the upper lip properly.