Orbicularis Oris - Podcast Version 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 (2026) 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 Pro Feature - Dissection Atlas Prosection of the face, demonstrating the anterior facial muscles. Prosection of the face, demonstrating the anterior facial muscles. You've Discovered a Pro Feature Access our Dissection Image Library Enhance your understanding with high-resolution dissection images showcasing real-life anatomy. Learn More Frequent questions What is the orbicularis oris muscle? The orbicularis oris is a facial muscle responsible for controlling the movements of the lips. It acts as the primary sphincter of the oral cavity. What are the attachments of the orbicularis oris? The orbicularis oris originates from the maxilla and surrounding muscles of the cheek, inserting into the skin and mucous membrane of the lips. What is the primary action of the orbicularis oris? The main function of the orbicularis oris is to close the lips, effectively narrowing the oral opening during various activities such as speaking and eating. Which nerve innervates the orbicularis oris? The orbicularis oris is innervated by the buccal branches of the facial nerve, which facilitate its movement and function. What is the blood supply to the orbicularis oris? The blood supply to the orbicularis oris comes from the superior and inferior labial branches of the facial artery, ensuring adequate perfusion for its function. Rate This Article