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
Where dos the depressor labii inferioris originate
mandible
Where does the depressor labii inferioris insert
skin of lower lip
What are the actions of the depressor labii inferioris
depresses lower lip
Where does the depressor anguli ori originate
mandible
Where does the depressor anguli ori insert
angle of mouth
What are the actions of the depressor anguli ori
draws angle of mouth laterally and inferiorly
Where does the levator anguli oris originate
inferior to infraorbital foramen
Where does the levator anguli oris insert?
skin off lower lip and orbicularis oris
What are the actions of the levator anguli oris
draws angle of mouth laterally and superiorly
Where does the buccinator originate
alveolar processes of mandible and maxilla
pterygomandibular raphe
Where does the buccinator insert
orbicularis oris
What are the actions of the buccinator?
presses cheeks against teeth (sucking, blowing)
Where does the risorius originate
fascia over parotid gland
Where does the risorius insert
skin @ angle o the mouth
What are the actions of the risorius
draws angle of mouth laterally (fake smile)
Where does the mentalis originate
mandible
Where does the mentalis insert
skin of chin
What are the actions of mentalis
elevates and protrudes lower lip and pulls skin of chin up
What is the origin of the platysma
fascia over deltoid and pec major
What is the insertion of the platysma
mandible
What are the actions of the platysma
draws outer part of lower lip inferiorly and posteriorly (pouting)
What is the origin of the orbicularis oculi
medial wall of orbit
What is the insertion of the orbicularis oculi
circular path around orbit
What are the actions of the orbicularis oculi
closes eye
What is the origin of the corrugator supercilli
medial end of supercillary arch of frontal bone
Where does the corrugator supercilli insert
skin of eyebrow
What are the actions of corrugator supercilli
draws eyebrows inferiorly and wrinkles skin of forehead (frowning)
How many muscles move the mandible? What are they?
4: masseter, temporalis, medial/lateral pterygoid
What nerve are all the muscles that move the mandible innervated by
CNV Trigeminal
What is the origin of the masseter
maxilla and zygomatic arch
What is the insertion of the masseter
angle and ramus of the mandible
What are the actions of the masseter
protract + elevates mandible
What is the origin of the temporalis
temporal bone (fossa)
What is the insertion of the temporalis
coronoid process and ramus of mandibl
What are the actions of the temporalis
elevate and retract the mandible
What is the origin of the media pterygoid
medial surface of lateral portion of pterygoid process and maxilla
What is the insertion of the medial pterygoid
angle and ramus of mandible
What are the actions of the medial pterygoid
elevates and protracts mandible + lateral movements
What is the origin of the lateral pterygoid
greater wing and lateral surface of lateral portion of the pterygoid process of sphenoid
What is the insertion of the lateral pterygoid
condyle of mandible ; tmj
What are the actions of the lateral pterygoid
protract, depress, lateral movements of mandible