The rissorius muscle is a narrow bundle of |fibers|. It originates from the ~fascia~ just above the |masseter| muscle and extends horizontally forward to insert in the skin at the angle of the |mouth|. This muscle pulls the side of the |mouth| backward and outward (toward the earlobe). It is one of the most variable of the facial muscles. Many people have no |risorius| muscle, while others have an expansive one. Some have the muscle on one side only.
