Anterior Dilator Naris Muscle, Lateral View

Description

Arising from the maxilla near the canine fossa, the anterior dilator naris (dilator naris anterior) courses superiorly and medially into the mobile soft tissue of the nasal ala, lying superficial to the lateral nasal cartilage and just lateral to the anterior naris. From a lateral profile, its short fibers sit anterior to the facial slip of the levator labii superioris alaeque nasi and blend with neighboring alar muscles at the margin of the nostril. Surrounding context includes the orbicularis oculi at the orbital rim, the zygomaticus major and minor over the zygoma, and the orbicularis oris encircling the mouth, with the masseter and temporalis defining the masticatory region posteriorly and the sternocleidomastoid marking the lateral neck. Small muscle. Big effect. Seeing the anterior dilator naris laterally matters because alar mechanics are three-dimensional, and the vector of pull that widens the nostril is easiest to appreciate when the alar base, nasal tip, and upper lip are all in the same plane. Weakness or denervation of the nasal musculature, as in facial nerve (CN VII) palsy, can contribute to dynamic nasal valve collapse and visible alar asymmetry during inspiration. This orientation also supports procedural planning for functional rhinoplasty and alar base surgery, where preserving or intentionally modifying the dilator naris and adjacent fibromuscular attachments helps balance airflow improvement against unwanted changes in nostril shape. Otolaryngology and plastic surgery educators can drop this figure into modules on the external nose, nasal valve function, and soft-tissue anatomy of the ala, while dental and maxillofacial audiences often pair it with perioral and maxillary muscular attachments near the canine fossa. It also fits cleanly into head and neck anatomy labs or journal figures discussing facial expression musculature and targeted chemodenervation around the nasal ala. Anatomical accuracy verified by SciePro's Medical Advisory Board.