3 - Growth and Development (complete)

Question 1

Growth Vs. Development

Answer 1

growth is the anatomical change in number and/or size of cells/tissues/organs
Development is the behavioral change of complexity, differentiation, and organization

Question 2

The head makes up what percent of the bodies cephalocaudal measurement at 3 months in utero, birth, and adult hood

Answer 2

3 months = 50%
birth = 30%
adult = 12%

Question 3

How does the growth of the cranium and face go

Answer 3

cranium grows first, then mandible, then maxilla.

infants have larger craniums, smaller faces, Adults have smaller craniums, and larger faces

Question 4

How does the growth of the mandible compare to the maxilla

Answer 4

the mandible grows later and larger than the maxilla

Question 5

How does the rate of growth of the following compare
lymphoid
neural
maxillary
mandible
somatic
genital

Answer 5

lymphoid - peaks at 10, decreases to adulthood
neural - finished growing at 6-7
maxillary - gradually grows up to 20 years
mandible - S-curve, grows when young and at puberty
somatic - S-curve, grows when young and at puberty
genital - begins at puberty

Question 6

What does the growth of the mandible correlate with

Answer 6

puberty

Question 7

Which is better to tell whether there was an acceleration or deceleration of growth. Distance curves or Velocity curves

Answer 7

Velocity curves, shows height gain per year over time.

Question 8

Why do we use growth charts for kids

Answer 8

to determine whether there is an unexpected change in growth patterns

Question 9

What is individual variability, and how does it change with increasing age

Answer 9

individual variability is the difference in timing of growth spurts, puberty, and menarche. it decreases with increased age

Question 10

When does menarche typically occur

Answer 10

1-1.5 years after peak growth

Question 11

how do growth patterns look for early and late maturers when using biological age instead of chronological age

Answer 11

when using biological age (onset of menarche) growth patterns look very similar and become more predictable

Question 12

How does growth of facial width, length and height occur

Answer 12

facial width is completed when puberty begins
facial length growth is greatest at puberty and rapidly declines into adulthood
facial height grows at a steady rate into adulthood

Question 13

how does the mandible condyloid and coronoid processes and zygomatic arch grow

Answer 13

mandible grows by bone apposition to the surface (addition of bone to the surface)
zygomatic arch grows by apposition of bone to the surface and internal resorption

Question 14

How does soft tissue grow, how does hard tissue grow

Answer 14

soft tissue grows via interstitial growth

hard tissue grows via direction appositional (periosteum) growth (addition of new bone to the surface)

Question 15

What is the difference between modeling and remodeling

Answer 15

modeling is the formation of new bone (either endochondral or intramembranous)
Remodeling is the achievement of final bone shape through apposition and resorption

Question 16

What is endochondral ossification and where in the head does it occur

Answer 16

calcification of a plate of cartilage into bone at centers of ossification
it occurs at the base of the cranium and in the mandibular condyle

Question 17

What is intramembranous ossification and where in the head does it happen

Answer 17

bone forms directly in the mesenchyme without the formation of cartilage
it occurs in cranial vault, maxilla, and the mandible except for the mandibular condyle

Question 18

What is cortical shift

Answer 18

deposition of bone on the periosteal surface and resorption of bone on the enosteal surface = bone relocation

Question 19

What are primary and secondary displacement

Answer 19

primary = movement of a bone due to bone growth
secondary = movement of a bone from displacement of other bones and soft tissue (nasomaxillary complex)

Question 20

What makes up the cranial vault, cranial base, and face

Answer 20

cranial vault = bone covering the upper and outer surface of the brain
Cranial base = bony floor of the brain (between vault and face)
Face = nasomaxillary complex and mandible

Question 21

How does the cranial vault grow

Answer 21

by intramembranous ossification, that is stimulated by the growing brain. apposition of bones at the sutures, and remodeling on the inner and outer bone surfaces

Question 22

How does the cranial base grow

Answer 22

initially via endochondrial ossification

Question 23

what are the three synchondroses found in the cranial base

Answer 23

spheno-occipital
inter-spheno
spheno-ethmoid

Question 24

What are the steps of growth of the nasomaxillary complex

Answer 24

1. passive growth, being pushed by the growing cranial base (occurs until about 6)
2. active growth via apposition of bone at the sutures between maxilla and cranium (after age 6)
3. surface remodeling, anterior surface undergoes resorption
4. bone addition to the maxillary tuberosity for erupting molars

Question 25

What is an example of when bone is added in the direction of the movement

Answer 25

the palate, it moves down and forward, and bone is being deposited on the oral side, and resorbed on the nasal side

Question 26

what is an example of when bone is resorbed in the direction of movement

Answer 26

the anterior maxilla, it moves down and forward, and bone is being removed on the anterior maxilla and in the alveolar process

Question 27

what determines if maxillary width increase is possible

Answer 27

as long as the midpalatal suture is patent growth can occur

Question 28

How does the mandible grow

Answer 28

endochondral ossification on the mandibular condyle

appositional growth and remodeling on the mandibular body

Question 29

Where does most of the growth of the mandible occur

Answer 29

the posterior surface of the ramus. The mental part of the mandible doesn’t move, it just grows backwards and upwards

Question 30

What is the difference between a growth site and a growth center

Answer 30

growth site is anywhere that bone growth occurs, but there is no innate growth potential. it grows due to external influences
growth centers are places with genetically controlled growth potential
(all growth centers are growth sites, but not all growth sites are growth centers)

Question 31

is condylar cartilage a growth center

Answer 31

nope