Week 3 Flashcards
What is the frontalis muscle
○ Thin and wide muscle located on the forehead
○ It raises the eyebrows & wrinkles the skin of the forehead
What pharyngeal arch do the facial expression muscles come from
second
What is the frontalis attached to
○ It goes from the dermis of the forehead and runs into a flattened tendon called the epicranial aponeurosis
What are the 3 parts of the orbicularis oculi
orbital
palpebral
lacrimal
Describe the orbital part of the orbicularis oculi
□ Largest and extends onto the face some distance beyond the orbital rim
What does the orbital part of the orbicularis oculi do
□ Orbital part is involved in forced closure (screwing up) the eye
What do some of the fibres of the orbicularis oculi muscles insert into
□ Some of the fibres of the upper part of the orbicularis oculi muscle are inserted into the eyebrow and have been termed the depressor supercilii muscle i.e depressing the eyebrow
What does the palpable part of the orbicularis oculi do
□ Central part, confined to the eyelids
□ Palpable part involved in closing eyelids without effort i.e involuntary blinking
What is the lacrimal part of the orbicularis oculi for
□ Dilates the lacrimal sac and so aids the flow of tears into the sac
Where is the procerus muscle seen
around the bridge of the nose - arises from the nasal bone and fibres insert into skin overlying nose
What is the procerus muscle for
○ When they contract they draw the ends of the brows together
Done in bright lights or when concentrating
Where is the orbicularis oris seen
Surrounds the opening of the mouth
○ Has 4 components to it: pars marginalis, pars peripheralis (superior/inferior)
What is the function of the orbicularis oculi
○ Surrounds the opening of the mouth
○ Keeps lips sealed when drinking or when speaking
Involved in closure, protrusion and pursing of the lips
What is the Lelevator labii superiorus seen
○ Arises from the maxilla
○ Deep to orbicularis oris
Where does the Levator labii superiorus seen
○ Arises from maxilla at inferior margin of the orbit
Inserts into skin overlying the upper lip and some of the fibres marge with the orbicularis oris
What is the primary action of the Levator labii superiorus seen
is to elevate the upper lip
Where is the depressor labii inferiorus muscle
○ Arises from mandible in front of mental foramen and inserts by converging with orbicularis oris muscle in the lower lip
What is the function of depressor labii inferiorus muscle
○ It depresses the lower lip and draws it laterally
The muscle is associated with the expression of irony
Where is the levator anguli oris seen
○ Arises from maxilla immediately below infraorbital foramen
○ Inserts into angle of the mouth
What is the primary action of the levator anguli oris
○ Elevates the corner of the mouth
What does the depressor anguli oris arise from
○ Arises from external oblique line of the mandible
○ Fibres pass upwards to the corner of the mouth where it is partly inserted here and partly into the orbicularis oris in the upper lip
What is the function of depressor anguli oris
Depresses the corner of the mouth and is said to be associated with the expression of grief
Where is the zygomaticus major seen
○ Takes origin from zygomatic bone
○ Passes down to corner of the mouth where it ‘mingles’ with orbicularis oris
What is the function of zygomaticus major
Pulls the corners of the mouth upwards and outwards as in laughing
Where is zygomaticus minor seen
○ Originates from zygomatic bone
○ Inserts into upper lip