Postnatal Development

Question 1

____ tissues are poorly studied

Answer 1

soft

Question 2

Bone develops due to…

Answer 2

genetics

Question 3

Soft tissue develops due to…

Answer 3

adaptation to bone

Question 4

______ plays a role in dental-alveolar complex & mandible

Answer 4

environment
-ex: mouth breathing can inhibit mandible growth

Question 5

What type of bones undergo endochondral growth?

Answer 5

long bones

Question 6

What way does endochondral bones grow?

Answer 6

from the middle outward

Question 7

What does endochondral growth grow from?

Answer 7

cartilage precursor

Question 8

What is another phrase for endochondral growth?

Answer 8

indirect growth

Question 9

What does indirect growth grow out from?

Answer 9

growth centers or growth plates

Question 10

What are the three facts about growth centers?

Answer 10

1. genetically programmed
2. mechanical stress (pressure/tension) has no effect
3. highly organized

Question 11

What are the steps of indirect/endochondral growth?

Answer 11

1. bone collar and hyaline cartilage model
2. primary ossification center
   3a. blood vessels grow in
   3b. secondary ossification center
3. articulation occurs and growth plate centers form

Question 12

What is a growth plate or center?

Answer 12

• Where the cartilage matrix is replaced by immature bone

*genetically programmed

Question 13

The mandible is a long bone: true or false.

Answer 13

FALSE

Question 14

What type of growth does the cranial base/chondrocranium use?

Answer 14

cartilaginous growth
*responds to long bone growth patterns

Question 15

What does the cranial base angle determine?

Answer 15

class I, II, or III
*related to specific malocclusion

Question 16

When does the intersphenoid synchondrosis fuse?

Answer 16

birth

Question 17

When does the spheno-ethmoidal synchondrosis fuse?

Answer 17

6 years

Question 18

When does the spheno-occipital synchondrosis fuse?

Answer 18

12-15 years

Question 19

What is the most important type of bone growth in dentistry?

Answer 19

intramembranous bone growth
(90% of craniofacial growth)

Question 20

How does intramembranous bone growth work?

Answer 20

Replacement of connective tissue with bony tissue

Question 21

Intramembranous growth will result in ________ of other structures in space

Answer 21

displacement

Question 22

What are the steps of intramembranous bone formation?

Answer 22

1. mesenchymal cell -> signaling factors
2. osteoblasts
3. ossification center
4. osteoid -> calcification
5. osteocytes
6. lamelar or cortial bone

Question 23

The bone formation occurs directly in a _________ in intramembranous ossification

Answer 23

vascularized mesenchyme

Question 24

_________ occurs throughout life to keep the bone in balance

Answer 24

remodeling

Question 25

What is an example of too much bone formation (apposition)?

Answer 25

tori

Question 26

What is an example of too little bone formation (resorption)?

Answer 26

periodontal disease

Question 27

New bone forms on the _______ aspect of the bone while bone is resorbed on the ______ aspect

Answer 27

external
internal

Question 28

True/False: The ratio is not always proportional as some structures must increase in size during growth

Answer 28

True

Question 29

What is the V principle of Enlow?

Answer 29

• A bony structure will be displaced during growth.
• In order to preserve the shape, parts of the bone will receive new bone and parts will resorb

Question 30

Placing a V on a ________ osseous structure will determine the direction of growth

Answer 30

growing

Question 31

________ surfaces are in the center of the V

Answer 31

Apposition

Question 32

__________ surfaces are located outside the V

Answer 32

Resorbing

Question 33

What type of growth is direct?

Answer 33

intramembranous

Question 34

Displacement of bone in space by resorption-apposition is called?

Answer 34

drift

Question 35

What is the drift principle?

Answer 35

allows volume increase and displacement in space while maintaining the proper shape