Quick Facts
Origin: Mental tubercle and oblique line of mandible.
Insertion: Angle of mouth.
Action: Depresses angle of mouth.
Innervation: Buccal and marginal mandibular branches of facial nerve (CN VII).
Arterial Supply: Inferior labial artery and mental branch of inferior alveolar artery.
Origin
The depressor anguli oris muscle originates from the mental tubercle and the oblique line of the mandible.
Insertion
The depressor anguli oris muscle blends with the skin at the angle of the mouth and with the orbicularis oris, risorius, and levator anguli oris muscles. It is continuous inferiorly with platysma. It may also blend with its contralateral counterpart.
Actions
The depressor anguli oris muscle depresses the angle of the mouth and also draws it laterally. This action is used when opening the mouth and when expressing sadness (Standring, 2016).
List of Clinical Correlates
- Bell’s palsy
References
Standring, S. (2016) Gray's Anatomy: The Anatomical Basis of Clinical Practice. Gray's Anatomy Series 41st edn.: Elsevier Limited.
Learn more about this topic from other Elsevier products
Depressor Anguli Oris Muscle
Depressor anguli oris (DAO)—The depressor anguli oris muscle draws the angle of the mouth downwards and laterally in opening the mouth and in expressing sadness or questioning.
