Depressor anguli oris muscle

Dr Daniel J Bell et al.

The depressor anguli oris muscle (also known as the triangularis muscle) is one of the muscles of facial expression.


  • origin: oblique line of the mandible
  • insertion: 
    • angle of the mouth
    • superficial fibers from both sides merge to form the transversus menti
  • innervation: facial nerve
  • action: 
    • depresses the angle of the mouth, e.g. frowning
Anatomy: Head and neck

Anatomy: Head and neck

Article information

rID: 55052
System: Head & Neck
Section: Anatomy
Synonyms or Alternate Spellings:
  • Depressor of the angle of the mouth muscle
  • Depressor anguli oris
  • Triangularis muscle

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