Anatomy, Head and Neck, Mastication Muscles

The primary muscles of mastication (chewing food) are the temporalis, medial pterygoid, lateral pterygoid, and masseter muscles.  The four main muscles of mastication attach to the rami of the mandible and function to move the jaw (mandible).  The cardinal mandibular movements of mastication are elevation, depression, protrusion, retraction, and side to side movement.  To augment the process of eating, the muscles of mastication also move the mandible in a side to side motion to assist in the grinding of food.  The muscles of mastication also function to approximate (bring together or close) the teeth.  The superficial muscle of the neck, the platysma muscle, also assists with depression of the mandible against resistance.[1]
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