The levator anguli oris is a facial muscle located in the face's upper lip and cheek region. It extends from the maxilla (upper jaw) to the corner of the mouth and is responsible for elevating and retracting the corner of the mouth, creating a smile. The levator anguli oris muscle also contributes to other facial expressions, such as smirking or sneering. The muscle is innervated by the buccal branch of the facial nerve (cranial nerve VII) and works in conjunction with other facial muscles to produce a range of facial expressions. Dysfunction or weakness of the levator anguli oris muscle can lead to difficulties with speech, eating, and facial expressions, such as smiling or puckering the lips.