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Flashcards in Lecture 3 Deck (39):
1

When is extraction of an ankylosed primary tooth recommended?

-If the primary tooth drops below the height of contour

2

T/F Growth is controlled both by genetic factors and environmental factors

True

3

What is the theory of genetic blue print model?

-The role of genetic preprogramming has long been presumed by many to have a fundamental influence in establishing basic facial pattern

4

How do bioelectric signals occur?

-From distortions of the crystals in the bone that can lead to the triggering of osteoblastic and osteoclastic responses

5

What is Wolffs law?

-Bone in a healthy person or animal will adapt to the loads under which it is placed, if loading on a particular bone increases, the bone will remodel itself over time to become stronger

6

What is the mechanostat theory?

-Bone growth and loss is stimulated by the local mechanical elastic deformation of bone

7

There is a linear relationship in a healthy body for the growth of bone between what?

-Muscle cross sectional area and bone cross sectional area

8

What is a growth site?

-A location at which growth occurs

9

What is a growth center?

-Location at which independent growth occurs regardless of the growth and development of adjacent structures

10

T/F The pressure created by growth at the sutures, causes the maxilla to be pushed downward and forward

False
-People used to think this was true but later discovered it was not true

11

If a piece of epiphyseal plate is transplanted somewhere else and it keeps growing does that make it a growth site or growth center?

-Growth center

12

Are sutures growth sites or growth centers?

-Growth sites

13

Synchondroses are growth centers or growth sites?

-Growth centers

14

Is the nasal septum a growth site or growth center?

-Growth center

15

What does growth typically refer to?

-increase in size, but it can tend to be more linked to change than anything else

16

T/F All of the tissue systems of the body grow at the same rate

False
-They do not grow at the same rate

17

What does a change in growth pattern indicate?

-Some alteration in the expected changes in body proportions

18

When is the peak growth for girls?

-Around 12`

19

When is the peak growth for boys?

-Around 14

20

T/F Boys will generally start growth sooner for a shorter amount of time?

-False
-Girls

21

What are the three cellular possibilities for growth?

-Hypertrophy
-Hyperplasia
-Cells secrete extracellular material

22

T/F Cartilage behaves like soft tissue

True

23

THe direct addition of new bone to the bones surface can and does occur through the activity of cells located where?

-Periosteum

24

T/F Bone is formed as a primary tissue

False
-It is never formed as a primary tissue

25

T/F Once bone is mineralized interstitial growth is impossible

True

26

The greatest period of cranial growth occurs between what age?

-Birth and 5 yrs

27

What serves as a major site of bone expansion during postnatal craniofacial growth?

-Sutures

28

For sutures to function as growth sites they need to remain in what state?

-An unossified state

29

What type of bones is the cranial vault made up of?

-Flat bones formed via intramembranous bone formation

30

What is the most complex structure of the human skeleton?

-Cranial base

31

What is the first region of the skull to reach adult size?

-Cranial base

32

How does the cranial base form?

-Endochondral ossification

33

What are the three pairs of cartilaginous precursors for the chondrocranium?

-Ethmoid prechordal
-Sphenoid hypophyseal
-Occipital parachordal

34

Histologically what do synchondroses look like?

-Two-sided epiphyseal plate

35

T/F Typically more bone deposition occurs on the ethmoid bone at the sphenoethmoidal synchondrosis

True

36

How does growth of the maxilla occur?

-Apposition of bone at the sutures by they periosteum

37

What direction does the maxilla grow?

-Downward and forward

38

What two ways accomplish the downward and forward growth of the maxilla?

-A push from behind created by cranial base growth
-By compensatory growth at the sutures in response to the displacement of the maxilla through soft tissue growth

39

Where is the maxilla attached?

-Anterior end of the cranial base