Dilator naris muscle

Dilator naris muscle forms the alar component of nasalis muscle, and is one of the muscles of the nose, a subset of the muscles of facial expression.

Summary

• origin: maxilla​​
• insertion: ​nasal ala
• innervation: facial nerve (VII)
• action: flaring of the nostril

Gross anatomy

Origin

• fibers originate from the maxilla proximate to the canine tooth, lateral to the origin of the myrtiformis muscle and medial to the transversalis muscle  

Insertion

• fibers run laterally deep to the levator labii superioris alaeque nasalis (LLSAN) muscle into the nasal ala

​​Arterial supply

• facial artery

Venous drainage

• facial vein

Innervation

• buccal nerve (branch of facial nerve (VII))​

Action

Its overall action is to oppose the compressor naris and dilate the anterior nares

Variant anatomy

Muscles of the nose vary in size between individuals and may be entirely absent .