growth and development of craniofacial structures

Question 1

cranial vault is formed by _____

Answer 1

intramembranous ossification

Question 2

cranial base is formed by____

Answer 2

endochondral ossification primarily, secondarily intramembranous ossification also takes place

Question 3

when does ossification of cranial vault occur?

Answer 3

8th week IUL

Question 4

all fontanella are sealed by 1 year and a half

Question 5

how does elongation of the spheno-occipital synchondroisis affect the cranio facial structure?

Answer 5

it allows the cranial base to grow upward and forwards—> pushing the face ( maxilla and mandible ) downward and forwards

Question 6

when does the spheno-occipital synchondrosis close?

Answer 6

18-20 yeasr , ususally earlier in girls than boys

Question 7

relevant clinical manifestations of cleidocranial dystosis :

Answer 7

fontenells failure to close / delay
-deficient maxilla ( looks like class III malocclusion )
-failure of tooth eruption (both primary and decidious )

Question 8

what is crousan syndrome ?

Answer 8

premature fusion of sutures causing alot of pressure on growing brain , it is treated using RED which slowly allows both bone and soft tissue to grow

Question 9

relevant manifestation of achondroplasia :

Answer 9

mid-face hypoplasia –> results in maxillary secondary displacment not occuring

Question 10

oral manifestations of patients with downs syndrome :

Answer 10

protruding tongue , large tongue , open bite

Question 11

relevant manifestations of aperts syndrome :

Answer 11

-high arched , narrow palate
-crowding
-deficient maxilla
-malformations of skull , face , hands , and feet

Question 12

ossification centers of the cranial vault :

Answer 12

-large portion of frontal bone
-2 parietal bone
-2 temporal bone
-occipital bone

Question 13

describe the appositional growth of the cranium :

Answer 13

growth of brain influences the resorbtion of the internal surface of the cranium while remodelling and deposition occurs on the outter surface

Question 14

when does the spheno-ethmoidal synchondrosis close?

Answer 14

5-7 years

Question 15

when does the inter-sphenoidal synchondrosis close?

Answer 15

just before birth

Question 16

growth of which synchondrosis influences the overall facial skeletal pattern ?

Answer 16

spheno-occipital synchondrosis

Question 17

when does the intra-occipital synchondrosis close?

Answer 17

3-5 years

Question 18

which kind of ossification mainly forms the maxilla?

Answer 18

intramembranous ossification

Question 19

maxilla is underdeveloped at time of birth due to:

Answer 19

absence of sinus or antrum