Orbicularis oris

orbicularis oris
(Science: anatomy, muscle) origin, by nasolabial band from septum of the nose, by superior incisive bundle from incisor fossa of maxilla, by inferior incisive bundle from lower jaw each side of symphysis; insertion, fibres surround mouth between skin and mucous membrane of lips and cheeks, and are blended with other muscles; action, closes lips; nerve supply, facial.
Synonym: musculus orbicularis oris, musculus sphincter oris, orbicular muscle of mouth, sphincter oris.

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