A6 - the face Flashcards
how may bones make up the viscerocranium?
14
what is the common embryonic origin of the muscles of facial expression?
2nd pharyngeal arch
all the muscles of facial expressions are innervates by what?
facial nerve
where do the muscles of facial expression insert?
dermis of the skin
what is the muscle of the scalp?
occipitofrontalis
describe the occipitofrontalis
- consists of 2 bellies (frontal and occipital), joined in the middle by an aponeurosis
- the muscle moves the scalp on the skull, wrinkles the skin on the forehead and elevates the eyebrows
what are the 2 muscles of the eyelids?
orbicularis oculi and corrugator supercilii
what are the 2 parts of orbicularis oculi?
orbital and palpebral
what do the 2 different parts of orbicularis oculi do?
- orbital — wrinkles the eyelids and closes them tightly
- palpebral — closes the eyelids gently
what does corrugator supercilii do?
draws the eyelids medially forming wrinkles in the forehead
what are the 3 muscles of the nostrils?
nasalis, depressor septi nasi and procerus
label the 3 muscles of the nose
label the muscles that act on the lips
what is the muscle of the cheek and its function?
buccinator — required for blowing and sucking and is also used to keep the bolus of the food between the teeth when chewing
what is the muscle of the neck and its function?
= platysma
- depresses the mandible and the angle of the mouth and tenses the skin over the inferior face and neck
what innervates all the muscles of mastication?
the mandibular branch of the trigeminal nerve (V3)
what nerves exit at where the arrows are pointing? where do the nerves arise?
describe infraorbital and mental nerves
a - infraorbital nerve = terminal branch of the maxillary division of CN V
d - mental nerve = branch of inferior alveolar nerve which arises from the mandibular division of CN V
label the muscles A-H
what are the 5 layers of the scalp?
S — skin
C — connective tissue — a fibrofatty layer that attaches the skin to the underlying aponeurosis.
many arteries and vins form an anastomosing network in this layer
A — aponeurosis (of occipitofrontalis)
L — loose areolar connective tissue — connects the aponeurosis to the periosteum of the skull. it
contains important emissary veins that connect the superficial veins of the scalp with the
diploic veins of the skull with the dural venous sinuses
P — pericranium — the periosteum covering the bones of the skull
what are the muscles of mastication?
- masseter
- temporalis
- medial pterygoid
- lateral pterygoid
all the muscles of mastication insert into the ____ and act on the _____
- mandible
- temporomandibular joint
origin, insertion and action of temporalis
- O = temporal fossa
- I = coronoid process of mandible
- A = elevation and retraction of mandible
origin, insertion and action of masseter
- O = zygomatic arch
- I = lateral surface of ramus and angle of mandible
- A = elevation of mandible
origin, insertion and action of medial pterygoid
- O :
head 1 = medial aspect of lateral pterygoid plate
head 2 = tuberosity of maxilla - I = medial surface of ramus and angle of mandible
- A = laterally moves and protracts mandible