Depressor anguli oris

  • The depressor anguli oris (also depressor anguli oris muscle, latin: musculus depressor anguli oris) is a facial muscle in the mouth area responsible for pulling the angle of the mouth downward, thus enabling a facial expression associated with frowning.

    Origin

    The depressor anguli oris originates from the base of the mandible, specifically, from the oblique line that runs posteriorly and superiorly from each mental tubercle on the outer surface of the mandible.

    Insertion

    The depressor anguli oris inserts into the skin of the angle of the mouth.

    Action

    The main function of the depressor anguli oris is pulling the angle of the mouth downward. Contractions of the depressor anguli oris muscle participate in producing a facial expression of sadness.

    Innervation

    The depressor anguli oris is innervated by the marginal mandibular branch of the facial nerve (CN VII).

    Blood supply

    The depressor anguli oris receives arterial blood supply mainly from the inferior labial branch of the facial artery.