Anterior Dilator Naris Muscle Beneath the Skin, Lateral View

Description

Seen beneath the skin in lateral profile, the anterior dilator naris (dilator naris anterior) lies superficial to the lateral nasal cartilage and adjacent to the alar margin, blending with the nasalis and nearby fibers of levator labii superioris alaeque nasi. Its small fascicles track obliquely across the lateral wall of the nostril, positioned anterior to the piriform aperture of the maxilla and superior to the upper lip musculature. Posteriorly, the zygomatic arch and temporal region frame the facial skeleton, while the maxillary dentition and mandibular body provide inferior bony landmarks for orientation. Fine anatomy. Functionally, this muscle helps flare the ala nasi and stabilize the external nasal valve during inspiration, a point that matters when teaching nasal airflow mechanics and the distinction between internal and external valve compromise. In rhinoplasty and functional nasal surgery, lateral wall weakness and alar retraction can limit the effect of native dilator naris activity, and surgeons often assess dynamic alar collapse on profile view to decide on alar batten grafting or lateral crural support. Regional motor supply travels via buccal and zygomatic branches of the facial nerve (CN VII), so iatrogenic weakness from facial soft tissue dissection or post-traumatic nerve injury can present as reduced nostril flare and exercise-related nasal obstruction. Use this asset in head and neck anatomy teaching when you want students to connect named mimetic muscles to specific cartilaginous landmarks, or in an otolaryngology or facial plastics chapter illustrating dynamic nasal valve behavior and operative planning points along the ala. It also fits patient-facing surgical consent materials where a clear lateral depiction of the alar musculature helps explain expected changes in nasal contour and breathing. Anatomical accuracy verified by SciePro's Medical Advisory Board.