Masseter Origin, Insertion, Action, Innervation, Blood Supply
Deep portion: from the deep and medial surface of the zygomatic arch
Deep portion: upper half of the ramus and the lateral surface of the coronoid process of the mandible.
Primary Actions of the Masseter
1. Closing of the mouth
2. Clenching of the teeth. Secondary action
3. Assists with retraction of the mandible (deep portion)