Facial Muscles and Muscles of Mastication Flashcards
What are the facial muscles innervated by?
Facial nerve
General movements of the orbital group?
Control movement of the eyelid and so protect the cornea from damage
Name the muscles of the orbital group
Orbicularis oculi
Corrugator supercillii
Movements of the orbiculares oculi?
Inner palpebral part closes the eye gently Outer orbital part does it more forcefully
Actions of the corrugator supercillii?
Draws eyebrows together
Where is the corrugator supercillii located in relation to the orbicularis oculi? Desribe it.
Smaller
Posterior to the OO
Inserts into the skin of the eyebrow
Name the facial muscles of the nasal group
Nasalis Procerus Depressor septi nasi
Talk about the nasalis
Largest of the nasal group Split in two parts - transverse and alar Transverse compresses nares, alar opens them
Action of the procerus?
Most superior
Pulls eyebrows down
Action of the depressor septi nasi?
Pulls nose inferiorly, opening nares
Function of the orbicularis orbis?
Purses lips
Function of the buccinator?
Pulls cheeks inwards against teeth, preventing accumulation of food here
If the facial nerve is damaged and the person smiles, which side is affected depending on how the smile appears?
Tissues around mouth and cheeks sag Drawn across to opposite side to that affected while smiling
What are the muscles of mastication innervated by?
Mandibular nerve,(V3) a branch of the trigeminal nerve
Which pharyngeal arch are the muscles of mastication derived from?
1st pharyngeal arch
Name the muscles of mastication
Masseter Temporalis Medial pterygoid Lateral pterygoid
Which muscles raise the mandible?
Masseter/ Temporalis/ Medial pterygoid
Action of the temporalis?
Elevates mandible Retracts mandible, pulling jaw posteriorly
Action of the lateral pterygoid?
Protracts mandible, pushing jaw forwards Moves jaw from side to side
Which nerve supplies the occipitofrontalis muscle?
Facial nerve
Where can the facial nerve often be compressed to give Bell’s Palsy?
Near its exit from the cranium at the stylomastoid foramen
Which nerve passes through the parotid gland?
Facial nerve
How can you tell the difference between a stroke and Bell’s palsy?
Bell’s palsy - all muscles of facial expression are paralysed on one side
Stroke - frontal sparing. Occipitofrontalis and Orbicularis oculi are not paralysed due to their bilateral innervation
Which pharyngeal arch are the facial muscles derived from?
Second
Triangularis
Pulls down the corners of the mouth, as in sadness
Temporalis
Closes the jaw
Frontalis
Raises the eyebrows
Zygomaticus
smiling muscle
Raises the corner of the mouth
smiling muscle
Raises the corner of the mouth
Corrugator
Draws the eyebrows inferiorly and medially, frowning.
Orbicularis occuli
A band of muscles that surround the eye
Orbicularis oris
kissing muscle
Buccinator
muscles that compresses cheeks inward; whistling or kissing.
Risorius
laughter
Masseter
Closes the jaw
Triangularis
Pulls down the corners of the mouth, as in sadness
Depressor labii
depress lower lip
