Growth and Orthodontics

Question 1

With growth how does the head shape change and in which direction?

Answer 1

the face grows relative to the skull

Face grows mainly in height then and SP direction and least in width

Question 2

Which jaw grows more in the A-P direction? Who did these studies?

Answer 2

the lower jaw grows more in the AP direction BUT there is wide variation
Bjork

Question 3

How much does the ANB angle change by?

Answer 3

1 degree between ages 11-20

Question 4

What types of pattern of growth occur in the head?

Answer 4

intramembranous

enchondrolal

Question 5

Which bones grow via enchondral ossification and which are intramem?

Answer 5

Enchondral,: cranial base and mandibular condyle (condylar is fibrocartilage)
Intramembranous: all other bones

Question 6

How can you restrain the maxilla?

Answer 6

head gear and functional

Question 7

how can you restrain forward growth of the mandible?

Answer 7

you cant!

Question 8

What are the two growth rotations that can occur?

Answer 8

forward and backward

Question 9

How is growth controlled?

Answer 9

mainly genetic but some environmental

Question 10

Which growth curves can be used to monitor facial growth?

Answer 10

tanner growth curves can be used to monitor stature which parallels facial growth

Question 11

what happens to growth during puberty?

Answer 11

pubertal growth spurt, velocity increases again

Question 12

When is the pubertal growth spurt in females?

Answer 12

12 years

Question 13

when is the pubertal growth spurt in boys?

Answer 13

14 years

Question 14

what is the standard deviation on the pubertal growth spurt ages?

Answer 14

2 years

Question 15

when does the growth stop in girls?

Answer 15

16 years

Question 16

when does growth stop in males?

Answer 16

18 years

Question 17

what is the standard deveiation for the growth stop?

Answer 17

2 years

Question 18

Can skeletal pattern be predicted?

Answer 18

1. Not very reliably

2. Can assume that everyone grows more class 3 with age

Question 19

Can the pubertal growth spurt be predicted?

Answer 19

No

Can predict the average age of growth spurt but can see what is happening

Question 20

Can orthodontic treatment influence growth?

Answer 20

A little bit

Question 21

What appliances can we use to influence the maxillary growth?

Answer 21

Head gear and functionals

Question 22

What appliances are used to enhance the growth of mandible?

Answer 22

Functionals

1-2mm

Question 23

T/F

There is nothin to restrain the growth of the mandible?

Answer 23

T

Question 24

What can you use to increase anterior maxillary growth?

Answer 24

Reverse head gear

Question 25

What is the significance of growth rotations?

Answer 25

Late incisor crowding

Question 26

What is the clinical significance of growth in ortho?

Answer 26

1. Unpredictable change in growth can affect treatment 2. Excessive vertical growth can lead to AOB 3. Treat class 3 cases later and treat class 2 earlier 4. Growth helps to reduce overbites 5. Growth essential for spontaneous alignment and space closure following extractions 6. Orthognathic surgery should be after growth stops 7. Implants placed once growth stopped 8.

Question 27

How can you predict growth?

Answer 27

Tanner growth curves

Question 28

What do tanner growth curves show?

Answer 28

Used to monitor stature which parallels facial growth

Question 29

What does the head consist of?

Answer 29

The cranium and the face

Question 30

Up until what age does the intercanine width increase?

Answer 30

Until age 10

Question 31

T/F during growth the ANB angle gets larger?

Answer 31

``` F Because everyone becomes more class 3 ```

Question 32

By how much does the ANB angle reduce?

Answer 32

Between ages 11-20 it reduces by 1 degree plus or minus 2,5

Question 33

What percentage of people will becomes more class 3 and class 2 and by how much?

Answer 33

15% by more than 3.5 degrees | 5% by more than 6 degrees

Question 34

What are the stages to mandibular growth ?

Answer 34

Intramembranous and secondary cartilage forms Condylar cartilage is an example of this Later growth and remodelling due to Intramembranous

Question 35

T/F periosteal growth can be influenced by pressure and tension?

Answer 35

T

Question 36

When is growth fastest?

Answer 36

In utero

Question 37

What happens between birth and puberty?

Answer 37

Decrease in velocity

Question 38

What happens to growth during puberty?

Answer 38

Reversal of the decreased velocity and during pubertal growth spurt and then there is a rapid decline

Question 39

T/F most people will have a jaw relationship that remains the same with growth?

Answer 39

T But some will have significant changs

Question 40

What are the possible environmental changes that will affect frowth?

Answer 40

Nutrition: softer food Mouth breathing: small effect on growth Bottle feeding: no affect Jaw tongue and lip exercises no affect

Question 41

T/F you can tell when the pubertal growth spirt is happening?

Answer 41

T