Orbicularis Oris - Podcast Version TeachMeAnatomy 0:00 / 0:00 1x 0.25x 0.5x 0.75x 1x 1.25x 1.5x 1.75x 2x The orbicularis oris is an oral muscle of facial expression. It is the main sphincter muscle of the lips. Attachments – Arises from the maxilla and from the other muscles of the cheek. It inserts onto the skin and mucous membrane of the lips. Action – Closes the lips to narrow the oral opening. Innervation – Buccal branches of the facial nerve. Blood supply – Superior and inferior labial branches of the facial artery By TeachMeSeries Ltd (2025) Fig 1The main oral muscles of facial expression. Note how the fibres of buccinator and orbicularis oris blend together Pro Feature - 3D Model You've Discovered a Pro Feature Access our 3D Model Library Explore, cut, dissect, annotate and manipulate our 3D models to visualise anatomy in a dynamic, interactive way. Learn More Rate This Article