Zygomaticus major muscle

The zygomaticus major is a muscle in the face that is necessary for facial expression. It draws the angle of the mouth into a smile. Like all muscles that are a part of facial expression, the zygomaticus major is innervated by the facial nerve (cranial nerve 7).

The zygomaticus major extends from each zygomatic arch, and raises the corners of the mouth in a smile. Some people have variations to this muscle which may cause dimples.