Buccinator muscle

The buccinator is a thin quadrilateral muscle, occupying the interval between the maxilla and the mandible at the side of the face.

Action
Its action is to pull back the angle of the mouth and to flatten the cheek area.

Origin and insertion
It arises from the outer surfaces of the alveolar processes of the maxilla and mandible, corresponding to the three molar teeth; and behind, from the anterior border of the pterygomandibular raphé which separates it from the Constrictor pharyngis superior.

The fibers converge toward the angle of the mouth, where the central fibers intersect each other, those from below being continuous with the upper segment of the Orbicularis oris, and those from above with the lower segment; the upper and lower fibers are continued forward into the corresponding lip without decussation.

Innervation
Motor innervation is from the facial nerve (cranial nerve VII), and sensory innervation is from the buccal branch of the trigeminal nerve (cranial nerve V).