The masseter muscle is part of the muscles of mastication, originates from the zygomatic arch, and inserts at the masseteric tuberosity at the angle of the mandible[^1].
Anatomy
Fiber orientation
The muscle is divided into a superficial, more powerful portion, whose fibers run obliquely, and a deep portion, whose fibers run vertically and originate from the inner surface of the zygomatic process of the Temporal bone and also from the temporal fascia.
Innervation
The masseter muscle is innervated by the masseteric nerve, which arises from the mandibular nerve.