Muscles of facio-maxillary region

Question 1

functions of facial muscles:

Answer 1

• sphincters + dilators of orifice of face

Question 2

structure of facial muscles (how they are + origin + innervation):

Answer 2

• subcutaneous
• origin = fascia or bone
• insertion = into the skin
• innervation = facial nerve (CN VII)

Question 3

muscles of temporal branche (le truc des 5 doigts sur la face):

Answer 3

• frontalis
• orbicularis oculi
• corrugator supercilii

Question 4

muscles of zygomatic branches:

Answer 4

orbicularis oculi

Question 5

muscles of buccal branches:

Answer 5

• orbicularis oculi
• buccinator
• zygomaticus

Question 6

muscles of marginal mandibular branches:

Answer 6

• mentalis
• depressor labii inferioris
• depressor anguli oris

Question 7

muscles of cervical branches:

Answer 7

platysma

Question 8

muscles of the scalp:

Answer 8

occipito-frontalis

Question 9

muscles of the eyelid:

Answer 9

• orbicularis oculi
• corrugator supercilia
• levator palpebrae superioris

Question 10

muscles of the nose:

Answer 10

• nasalis
• procerus
• depressor septi
• ## dilator naris posterior

Question 11

muscles of the mouth:

Answer 11

• orbicularis oris
• buccinator
• levator anguli oris
• depressor anguli oris
• depressor labii inferioris
• mentalis
• risorius
• zygomaticus
• levator labii superioris
• levator labii superioris alaeque nasi

Question 12

muscles of the ear:

Answer 12

• anterior auricular
• posterior auricular
• superior auricular

Question 13

action of frontal belly:

Answer 13

wrinkles forehead, raises eyebrows, draws scalp backwards

Question 14

the orbicularis has 2 major parts which are:

Answer 14

• orbital + palpebral parts

Question 15

action of the orbicularis oculi:

Answer 15

sphincter muscle of the eyelid
- orbital part = closes voluntarily + forcefully + produces wrinkles in forehead
- palpebral part = involuntarily + softly

Question 16

action of cogurrator supercilli:

Answer 16

draws eyebrows medially and downward, causing vertical wrinkles above the nose and active when frowning

Question 17

action of levator palpebrae superioris:

Answer 17

(most superior muscle in the orbit)
contraction of the muscle raises the eyebrow

Question 18

action of nasalis:

Answer 18

• transverse part: compresses nasal aperture
• alar part: draws cartilage downward and laterally opening nostril

Question 19

action of procerus:

Answer 19

Draws down the medial angle of eyebrows, producing transverse wrinkles over the bridge of the nose.
- It can also contribute to an expression of anger

Question 20

action of dilators of nose (depressor spt nasi + dilator naris)

Answer 20

Depressor septi nasi:pulls the nose inferiorly, assisting the alar part of the nasalis in opening the nares.
- The Dilator naris muscle is a part of the nasalis muscle. It is divided into posterior and anterior parts:
Dilatator naris posterior
Dilatator naris anterior
Action: enlarge the aperture of the nares. Their action in ordinary breathing is to resist the tendency of the nostrils to close from atmospheric pressure.

Question 21

action of the orbicularis oris:

Answer 21

Contraction of the orbicularis oris narrows the mouth and closes the lips. Its function is apparent when ‘pursing’ the lips as during whistling.

Question 22

lower oral muscles:

Answer 22

DEPRESSOR ANGULI ORIS
DEPRESSOR LABII INFERIORIS
MENTALIS

Question 23

action of Buccinator:

Answer 23

The Buccinators compress the cheeks so that, during the process of mastication, the food is kept under the immediate pressure of the teeth. When the cheeks have been previously distended with air, the Buccinator muscles expel it from between the lips, as in blowing a trumpet.
It aids in whistling and smiling, and in neonates, it is used to suckle

Question 24

action of mentalis:

Answer 24

raises and protrudes the lower lip as it wrinkles the skin of the chin; helps position the lip when drinking from a cup or when pouting.

Question 25

upper oral muscles:

Answer 25

Risorius
Zygomaticus major
Zygomaticus minor
Levator labii superioris
Levator labii superioris alaeque nasi
Levator anguli oris

Question 26

action of levator labii superioris:

Answer 26

retracts + everts upper lip

Question 27

action of levator labii superioris alaeque nasi:

Answer 27

dilates nostril + elevates wing of nose and upper lip

Question 28

action of levator anguli oris:

Answer 28

raises the angle of the mouth while smiling

Question 29

action of risorius:

Answer 29

The risorius retracts the angle of the mouth to produce a smile, albeit an insincere-looking one that does not involve the skin around the eyes. Compare with a real smile, which raises the lips with the action of zygomaticus major and zygomaticus minor muscles and causes “crow’s feet” (A name for wrinkles in the outer corner of the eyes as the result of aging resembling crow’s feet) around the eyes using the orbicularis oculi muscles

Question 30

zygomaticus major and minor actions:

Answer 30

• zygomaticus major: Draws the corner of the mouth upward and laterally.
  It raises the corners of the mouth when a person smiles. Variations in the structure of this muscle may cause dimples.
• zygomaticus minor: Draws the upper lip upward

Question 31

action of levator labii superioris:

Answer 31

Raises upper lip; helps form nasolabial furrow, may assist in flaring the nares

Question 32

action of levator angulis oris:

Answer 32

it elevates the corner of the mouth and may help deepen the furrow between the nose and the corner of the mouth during sadness

Question 33

the articular components of the temporomendibular joint:

Answer 33

• mandibular fossa
• articular tubercle of temporal bone
• mandibular condyle

Question 34

what is the articular surface of the bones of the TMJ composed of ?

Answer 34

The articular surface of the bones is covered byfibrocartilage, not hyaline cartilage

Question 35

the 3 extracapsular ligaments that stabilize the TMJ:

Answer 35

Lateral ligament– runs from the beginning of the articular tubule to the mandibular neck. It is a thickening of the joint capsule and prevents posterior dislocation of the joint.
Sphenomandibular ligament– originates from the sphenoid spine and attaches to the mandible.
Stylomandibular ligament–a thickening of the fascia of the parotid gland. Along with the facial muscles, it supports the weight of the jaw.

Question 36

muscles of mastication and the hyoid muscles produce movements at this joint, the 2 divisions and their functions:

Answer 36

• Protrusion and Retraction: The upper part of the joint allows for the mandible’s protrusion and retraction–the jaw’s anterior and posterior movements.
• Elevation and Depression: The lower part of the joint permits elevation and depression of the mandible, which opens and closes the mouth. Depression is mostly caused bygravity.

Question 37

nerve supply of temporalis and masseter:

Answer 37

branches of mandibular division of trigeminal nerve

Question 38

action of temporalis:

Answer 38

elevates and retracts the mandible

Question 39

action of the masseter:

Answer 39

elevates and protrudes the mandible

Question 40

action of lateral pterygoid:

Answer 40

• bilateral: protracts mandible
• unilateral: pushes mandible to the opposite side

Question 41

action of the medial pterygoid:

Answer 41

• bilateral: pushes mandible forward
• unilateral: pushes mandible to the opposite side
• elevates the mandible

Question 42

some important relations to the TMJ:

Answer 42

Anteriorly: The mandibular notch and the masseteric nerve and artery
Posteriorly: The tympanic plate of the external auditory meatus
Laterally: The parotid gland, fascia, and skin
Medially: The maxillary artery and vein and the auriculotemporal nerve
Superiorly: middle cranial fossa with the Temporal lobe