The Temporalis muscle is one of the chewing muscles and is attached from the temple to the jawbone. Contraction and consequent shortening of this muscle pulls the jawbone upwards during the chewing process. The principle of the muscle transfer includes detaching the muscle from the jawbone and re-attaching it to the side of the mouth. Contraction and shortening of the muscle will then lead to pulling the side of the mouth upwards and the creation of a smile.