Buccinator - muscle of mastication
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 raphe.
The fibers converge toward the angle of the mouth, where the central fibers intersect each other, at the Orbicularis oris.
Action: on contraction, it pulls back the angle of the mouth and to flatten the cheek area. This helps in pushing the food back onto the occlusal surfaces of the teeth from the buccal vestibule during chewing.