Marginal mandibular branch of facial nerve

Nerve: Marginal mandibular branch of facial nerve
Plan of the facial and intermediate nerves and their communication with other nerves. (Labeled at center bottom, second from bottom, as "Mandibular".)
The nerves of the scalp, face, and side of neck.
Latin	ramus marginalis mandibularis nervi facialis
Gray's	subject #202 905
From	facial nerve

The marginal mandibular branch of facial nerve passes forward beneath the Platysma and Triangularis, supplying the muscles of the lower lip and chin, and communicating with the mental branch of the inferior alveolar nerve.

Muscles innervated

Depressor labii inferioris- lowers bottom lip down and laterally. Origin: Anterior part of oblique line of mandible. Insertion: Lower lip at midline, blends with musle from opposite side.

Depressor anguli oris (Triangularis) - lowers corner of the mouth down and laterally. Origin: Oblique line of mandible below canine, premolar, and first molar teeth. Insertion: Skin at the corner of mouth and blending with orbicularis oris.

Mentalis - raises and protrudes lower lip as it wrinkles skin on chin. Origin: Mandible inferior to incisor teeth. Insertion: Skin of chin

Clinical significance

The marginal mandibular nerve may be injured during surgery in the neck region, especially during excision of the submandibular salivary gland or during neck dissections.

Additional images

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  Lateral head anatomy detail

External links

• SUNY Labs 23:06-0103 - "Branches of Facial Nerve (CN VII)"
• lesson4 at The Anatomy Lesson by Wesley Norman (Georgetown University) (parotid3)
• cranialnerves at The Anatomy Lesson by Wesley Norman (Georgetown University) (VII)
• http://www.dartmouth.edu/~humananatomy/figures/chapter_47/47-5.HTM

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained within it may be outdated.