skull, face, palate

Question 1

skull development

Answer 1

ant from neural crest

post from paraxial mesoderm

Question 2

fontanelles

Answer 2

ant, post, posterolateral, anterolateral

Question 3

craniosynostosis

Answer 3

premature fusion of cranial sutures
scaphocephaly- most common, skull low and narrow
brachycephaly- second most common, early fusion of coronal suture, skull short and wide

Question 4

frontonasal prominence

Answer 4

3 paired facial prominences from 1st arch form:
frontonasal prominence
maxillary prominence
mandibular prominence

Question 5

frontonasal prominence

Answer 5

forehead
bridge of nose and nasal septum
medial nasal prominences- apex of nose, philtrum of upper lip
lateral nasal prominences- ala of nose

Question 6

maxillary prominence

Answer 6

upper cheek

lateral portion upper lip

Question 7

mandibular prominences

Answer 7

chin
lower cheek region
lower lip
part of external ear

Question 8

nasal placodes

Answer 8

thickening of surface ectoderm form on frontonasal prominence and invaginate to form nasal pits

Question 9

development from nasal pits

Answer 9

mesenchyme surrounding pits proliferates to form the medial and lateral nasal prominences
medial nasal prominences fuse forming intermaxillary segment

Question 10

intermaxillary segment

Answer 10

intermaxillary segment then fuses will adjacent maxillary prominence to form upper lip
intermaxillary segement also gives rise to philtrum and primary plate

Question 11

upper lip

Answer 11

from medial nasal prominences and maxillary prominences

Question 12

lower lip

Answer 12

mandibular prominences

Question 13

nasolacrimal duct

Answer 13

maxillary prominence fuses w/lateral nasal prominence along nasolacrimal groove
nasolacrimal duct forms from ectoderm of nasolacrimal groove

Question 14

nasal cavities

Answer 14

nasal pits deepen and grow dorsally, produce nasal sacs
nasal sacs are separated from oral cavity by oronasal membrane (ruptures wk 6th and replaces by palate)
olfactory epi and CNI develop from nasal sac ectoderm

Question 15

paranasal sinuses

Answer 15

develop throughout puberty

Question 16

primary palate

Answer 16

during wk 6 primary palate froms from intermaxillary segment
fuses w/nasal septum above and lateral palatine shelves posteriorly

Question 17

secondary palate

Answer 17

lateral palatine shelves form from maxillary prominences
initially palatine shelves project inferomedially on each side of tongue
during wks 7-8 palatine shelves migrate superiorly and fuse with each other, the primary palate, and in midline w/nasal septum
ossification occurs in ant 2/3s of palate to form hard palate
incisive foramen in land mark btwn primary and secondary palates

Question 18

anterior cleft

Answer 18

extends through lip, alveolar part of maxilla to incisive fossa
caused by failure of maxillary prominence to fuse w/medial nasal prominence

Question 19

median cleft of lip

Answer 19

failure of medial nasal prominences to merge, rare

Question 20

posterior cleft

Answer 20

lack of fusion of lateral palatine plates

cleft palate and or uvula

Question 21

oblique facial cleft

Answer 21

failure of maxillary process to fuse w/lateral plate prominence
runs from mouth towards eye, results in nasolacrimal duct not being incorporated into face