Development of the Face Flashcards
(95 cards)
<p>When does face development first begin?</p>
<p>early 4th week</p>
<p>what happens in the early 4th week?</p>
<p>the face is derived from 5 facial prominences surrounding the stomodeum.</p>
<p>what is the stomodeum?</p>
<p>the primitive mouth</p>
<p>what are the facial prominences made up of?</p>
<p>neural crest cells</p>
<p>what are the 5 facial prominences?</p>
<p>1 frontonasal prominence
2 maxillary prominences
2 mandibular prominences</p>
<p>where is the frontonasal prominence?</p>
<p>cranial to stomodeum</p>
<p>where are the maxillary prominences?</p>
<p>lateral to the stomodeum</p>
<p>where are the mandibular prominences?</p>
<p>caudal to stomodeum</p>
<p>what do nasal placeodes develop from and when does this happen?</p>
<p>the ectodermal thickenings on the ventrolateral parts of the frontonasal prominence
occurs in late 4th week</p>
<p>what merges across the midline in the late 4th week?</p>
<p>mandibular prominences</p>
<p>why do the nasal placodes become depressed and when does this happen?</p>
<p>become depressed as mesenchyme surrounding nasal placodes proliferates to form horseshoe shaped elevations
occurs in the 5th week</p>
<p>what do the horseshoe shaped elevations of mesenchyme surrounding the nasal placodes consist of?</p>
<p>2 medial nasal prominences
| 2 lateral nasal prominences</p>
<p>when do the primitive nostrils and nasal cavities develop?</p>
<p>5th week</p>
<p>what are the primitive nostrils and nasal cavities?</p>
<p>in the 5th week nasal placodes invaginate becoming paired nasal pits following the development of the of medial and later nasal prominences</p>
<p>When the maxillary prominences grow medially what does it cause and when does this occur?</p>
<p>it presses the medial nasal prominences to move toward the midline
occurs in 7-10 weeks</p>
<p>the fusion of the medial nasal prominences forms what and when does this occur?</p>
<p>intermaxillary segment
| occurs in 7-10 weeks</p>
<p>what does the intermaxillary segment become and when does this occur?</p>
<p>philtrum
primary palate
medial maxilla
occurs in 7-10 weeks</p>
<p>what forms the secondary palate and when does this occur?</p>
<p>merging of the maxillary prominences
| occurs in 7-10 weeks</p>
<p>what allows for the formation of the upper lip?</p>
<p>fusion between medial nasal prominences and the maxillary prominences</p>
<p>what causes cleft lip and/or palate?</p>
<p>failure of the prominences to fuse</p>
<p>what do the lateral nasal prominences merge and fuse with?</p>
<p>the maxillary prominences</p>
<p>when do the structures of the face develop their characteristic form?</p>
<p>early fetal development</p>
<p>what causes the eyes to shift medially, resulting in their forward-looking orientation</p>
<p>enlargement of the brain</p>
<p>elongation of the mandible causes what?</p>
<p>the ear to appear to rise</p>
what migrate to develop the mm. of facial expression?
myoblasts from the second pharyngeal arch
when is the face fully developed?
the 14th week
facial defects of fetal alcohol syndrome will only occur if the mom drinks when?
during the 1st trimester
levator
elevate
depressor
move it down
labii
associated with lip
anguli
angle of mouth (smile, frown)
superioris
upper lip
inferioris
lower lip
obicularis
sphincter mm. (close eyes, close mouth)
oculi
eyes
oris
upper/lower lip
what are the mm. of the eye?
frontalis, orbicularis oculi, corrugator supercilii mm.
what does frontalis m. do?
raise eyebrow, wrinkle forehead
what does orbicularis oculi m. do?
close eyelids (sphincter)
what does corrugator supercilii m. do?
draw eyebrow inferior and medially
what are the mm. of the nose?
procerus, nasalis, depressor septi mm.
what does procerus m. do?
wrinkle skin over bridge of nose
what does nasalis m. do?
dilate nostrils
what does depressor septi m. do?
draw septum inferiorly
what are the mm. of the mouth?
orbicularis oris, levator labii superioris (+alaeque nasi), zygomaticus major/minor, levator anguli oris, risorius, buccinator, depressor anguli oris, depressor labii inferioris, mentalis mm.
what does orbicularis oris m. do?
close lips, shop lips during speech
what does levator labii superioris (+alaeque nasi) m. do?
elevate upper lip and angle of mouth
what does zygomaticus major/minor m. do?
elevate angle of mouth
what does levator anguli oris m. do?
elevate angle of mouth
what does risorius m. do?
retract angle of mouth
what does buccinator m. do?
compress cheeks
what does depressor anguli oris m. do?
depress angle of mouth
what does depressor labii inferioris m. do?
depress lower lip
what does mentalis m. do?
protrude lower lip?
what are the mm. of the ear?
anterior, superior, and posterior auricular mm.
what do the anterior, superior, and posterior auricular mm. do?
retract or elevate ear
what is the mm. of the neck?
platysma
what do the platysma m. do?
tense skin of neck
what is the n. that provides motor innervation to all mm. of facial expression?
facial n. (VII)
what foramen does the facial n. (VII) exit?
stylomastoid foramen
what happens when the facial n. (VII) exits the stylomastoid foramen?
it rapidly gives off a few motor br.
as the facial n. (VII) proceeds anteriorly what does it pass through and what is this significance?
the parotid gland where it divides into 5 br.
what are the 5 br. of the facial n. (VII)
Ten Zebras Bit My Cat Temporal Zygomatic Buccal Mandibular Cervical
```sensory innervation to the face is provided by what?
trigeminal n. (V)
What is the exception to the trigeminal n. (V) providing sensory innervation to the face?
great auricular n. (C2, C3)
what are the divisions of the trigeminal n. (V)?
Ophthalmic division (V^1) Maxillary division (V^2) Mandibular (V^3)
what are the 5 nn. in the ophthalmic division (V^1) of the trigeminal n.?
lacrimal n. - lateral upper eyelid supraorbital n. - middle upper eyelid and anterolateral forehead supratrochlear n. - medial upper eyelid and anteromedial forehead infratrochlear n. - medial canthus, lacrimal sac external nasal n. - nose (including the tip)
what are the 3 nn. in the maxillary division (V^2) of the trigeminal n.?
zygomaticotemporal n. - anterior part of the temporal fosa zygomaticofacial n. - prominence of cheek infraorbital n. - upper lip
what are the 3 nn. of the mandibular division (V^3) of the trigeminal n.?
auriculotemporal n. - skin anterior to ear (long) buccal n. (SENSORY) - skin and oral mucosa of cheek (NOT the same as the buccal branch of the facial n. (VII)) mental n. - chin and lower lip
V^3 has a motor component that supplies what?
the mm. of mastication. these are NOT considered part of the mm. of facial expression
What are the arteries that supply the face?
facial a. transverse facial a. supraoribital a. supratrochlear a.
what is the facial a. a branch off of?
external carotid a.
what is the transverse facial a. a branch off of?
superficial temporal a.
what is the supraorbital a. a branch off of?
ophthalmic a.
what is the supratrochlear a. a branch off of?
ophthalmic a.
what a. is the major supply to the face?
facial a.
what are the branches of the facial a. and what do they supply?
submental a. - chin inferior labial a. - inferior lip superior labial a. - superior lip lateral nasal a. - ala (side) and dorsum of the nose angular a. - superior part of the cheek and inferior eyelid
what does the transverse facial a. supply?
parotid gland and duct
what do the supraorbital and supratrochlear aa. supply?
upper eyelid, forehead, and scalp
What are the vv. that drain the face?
angular v. facial v. retromandibular v.
what does the angular v. drain?
supraorbital and supratrochlear vv.
what does the angular vv. communicate with and how?
communicates with the cavernous sinus via superior and inferior ophthalmic vv.
the communication of the angular vv. and the cavernous sinus can result in what and why?
because there are no valves restricting flow back to the cavernous sinus, this represents a potential route of infection from the face to dural sinuses ---> CNS infection
what is known as the danger triangle of the face?
communication of the angular vv. and cavernous sinus via the superior and inferior ophthalmic vv. due to a potential route of infection from face to dural sinuses---> CNS infection
what is the facial v.?
continuation of the angular v. (angular v. drains into the facial v.)
what does the facial v. drain to?
the internal jugular v.
what does the facial drain communicate with?
retromandibular v.
where is the retromandibular v.?
posterior to the mandible
what does the retromandibular v. drain?
maxillary v. and superficial temporal v.
what does the retromandibular v. join and what does it form?
joins with the posterior auricular v. and forms the external jugular v.
