The temporalis muscle is located in the temple area of the skull. It originates on the temporal lines on the parietal bone of the skull, and inserts on the coronoid process of the mandible. It’s main action is to close the jaw. The posterior and middle fibres bilaterally retrude the mandible. Acting individually, this muscle will deviate the mandible to the same side. Trigger points in this muscle refer into the teeth causing hypersensitivity, and into and above the eye and temple, causing headaches.