Marginal mandibular branch of the facial nerve Tags: Anatomical Structure, 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. thumbnail branch from Facial nerve Dorlands prefix r_02 Dorlands suffix 12690722 Gray page 905 Gray subject 202 Learn more... Loading...