muscles of facial expression osmosis video

scalp

• made up of 5 layers

  • skin

  • connective tissue

  • aponeurosis

  • loose connective tissue

  • pericranium (periosteum)

• first 2 layers are connected together tightly called the scalp proper

muscles of facial expression

• deep to skin in scalp, face and neck

• attached to bones or fascia

• muscular sheet forms and spreads across scalp face and neck

  • carries branches of facial nerve (cranial nerve 7)

occipitofrontalis muscle

• 2 bellies connected by epicranial aponeurosis

• frontal belly

• occipital belly

orbicularis oculi

• 2 parts

  • palpebral part

  • orbital part

• function

  • to close the eyelids

  • palpebral part closes eyelids gently

  • orbital part closes eyelids tightly

corrugator supercilii (eyebrow muscle)

• draws the eyebrows downward and medially when frowning

the nose

• 3 muscles

  • procerus

    • top between eyebrows

    • depresses medial ends of eyebrows

  • nasalis

    • bridge of nose

    • largest muscle of nose

    • 2 parts

      • transverse

        • contracts nostrils

      • alar

        • flares nostrils

  • levator (long name)

    • comes down on either side of nose

    • flares nostrils and upper lip

orbicularis oris

• encircles the mouth

• closes mouth by bringing lips together or protrudes lips

muscles of the upper lip

• zygomaticus minor

  • pull the upper lip upward

• zygomaticus major

  • elevates corner of mouth

• levator …. nasi

  • pull the upper lip upward

• levator labii superioris

  • pull the upper lip upward

• levator anguli oris

  • raises the corner of mouth

• risorius

  • retracts the corner of mouth

muscles of the lower lip

• depressor anguli oris

  • pulls the corner of mouth downwards to express sadness

• depressor labii inferioris

  • pulls the lower lip downward when sad or pouting

• both muscles of the lower lip are dilators of the mouth

muscle of the chin

• mentalis

  • elevates and protrudes the lower lip when pouting

muscle of the neck

• platysma

  • broad muscle

  • depresses mandible, draws corners of mouth downward sand tenses the skin and neck

  • extends towards the mandible and blends with facial muscles

  • tenses skin of neck to express stress

buccinator

• main function is to press against the cheek when drinking out of a straw