Muscles of the Head Flashcards
Where do the muscles of the facial expression lie?
within the subcutaneous layer of skin
Typically where does a muscle of facial expression originate and insert?
originate in a facial bone and insert into dermis of the skin
What do muscles of facial expression function as when they surround natural orifices of the head?
sphincter: to close
dialator: to open
What nerve are all muscles of facial expression innervated by?
CN VII Facial nerce
Antagonism of the muscles of the facial expression come from where?
elasticity of the skin
Where does the frontalis originate?
epicranial aponeurosis (galea aponeurotica)
What is the epicranial aponeurosis also known as?
Galea aponeurotica
Where does the frontalis insert?
skin superior to supraorbital margin
What are the actions of the frontalis?
draws scalp anteriorly, raises eyebrows
Where does the occipitalis originate?
occipital bone and mastoid process
Where does the occipitalis insert?
epicranial aponeurosis
What are the actions of the occipitalis
draws scalp posteriorly
What is the origin of the orbicularis oris
muscle fibres surrounding opening of mouth
Where does the orbicularis oris insert?
skin @ angle of the mouth
What are the actions of the orbicularis oris?
closes and protrudes lips (puckering)
Where does the zygomaticus major originate?
zygomatic bone
Where does the zygomaticus major insert?
skin @ angle of mouth and orbicularis oris
What are the actions of the zygomaticus major
draws angle of the mouth superiorly and laterally (smiling)
Where does the zygomaticus minor originate
zygomatic bone
Where does the zygomaticus minor insert
upper lip
What are the actions of the zygomaticus minor
elevates upper lip
Where does the levator labii superioris originate
superior to infraorbital foramen
Where does the levator labii superioris insert
skin @ angle of mouth and orbicularis oris
What are the actions of the levator labii superioris
raises upper lip
