Marginal mandibular branch of the facial nerve


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

Muscles innervated

The marginal mandibular branch innervates the following muscles:
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 due to lack of accurate knowledge of variations in the course, branches and relations.
An injury to this nerve during a surgical procedure can distort the expression of the smile as well as other facial expressions.
The marginal mandibular branch of the facial nerve is found superficial to the facial artery and facial vein. Thus the facial artery can be used as an important landmark in locating the marginal mandibular nerve during surgical procedures.

Additional images