The orbicularis oris lies between the skin and the |mucous membrane| of the |lips|. It consists of a bundle of |muscle fibers| that surround the |mouth| and extends upward to the |septum| of the |nose| and downward to the region between the lower lip and chin. These muscular |fibers| are partially derived from other facial muscle that are inserted into the |lips|. The orbicularis oris pulls the |lips| against the |teeth| and causes |lips| to close and pucker, as when kissing.
