Dilator naris muscle

Structure

The dilator naris muscle is divided into posterior and anterior parts.

• The dilator naris posterior is placed partly beneath the levator labii superioris muscle. It arises from the margin of the nasal notch of the maxilla, and from the minor alar cartilages. It is inserted into the skin near the margin of the nostril.
• The dilator naris anterior is a delicate fasciculus. It originates from the lateral crus of the major alar cartilage, more laterally. It inserts into the margin of the nostril, the alar groove. It is situated in front of the dilatator naris posterior muscle.

Nerve supply

The dilator naris muscle is supplied by the facial nerve (VII).