Growth And Development. Unit A:concepts Of Physical Growth And Development

Front 1

What is Growth?

Back 1

-Increase in size or number
-Increase in complexity

Front 2

What is development?

Back 2

-Loss of potential
-Increase in complexity

Front 3

What is a growth pattern?

Back 3

Consider a pattern for an article of clothing. As the pattern increases in size, thereare changes in some areas that are larger or smaller than changes in other areas. That is, it isn't just blown up like a balloon. Think about permanent teeth. There is a certain "pattern of growth" --> 6 year molars, mand centrals --> max. cenrals --> laterals --> canines

Front 4

Pattern of Growth?

Back 4

Refers to the predictable changes in body proportions over time as the individaul grows
Pattern = change of proportion/time.

Front 5

What is an example of a pattern of growth from in utero to birth?

Back 5

-2nd month in utero: head and face is 50% of total body length
-Birth: head and face is 25% of the total body length

Front 6

What is the Cephalocaudal gradient of growth?

Back 6

Axis of increased growth extending from HEAD toward FEET. Furthermore, within the face, structures closer to the brain grow more earlier and less later.

Front 7

Describe the Scammon Curve.

Back 7

Compares Lymphoid, Neural, Genital and General growth.
Neural - usually complete by 6 or 7 years.
General (muscle, bone, and viscera) - S-shaped curve, with a definite slowing of the rate of growth during childhood and an acceleration at puberty.
Lymphoid-proliferate far beyond the adult amount in late childhood and then undergo involution at the same time that growth of genital tissues accelerates rapidly.

Front 8

Describe how the percentile growth charts are used.

Back 8

Growth charts, expressed in percentiles, are often used to show where patients fit in height and weight relative to their peers and how their position changes oer time.

Front 9

What are the normal ranges in a percentile growth chart?

Back 9

The normal range in a percentile growth chart is from 3rd to 97th percentile.
Normal growth is shown on a growth chart not so much by being at the 50th percentile, as by maintaining about the same percentile over time.

Front 10

What is abnormal in the percentile growth chart?

Back 10

Crossing the percentiles- particularly crossing several of them - usually indicates abnormal growth and some problem. In this respect, height is a more sensitive indicator than weight.

Front 11

When is the most notable difference of growth?

Back 11

Differences between individuals of the same age and gender, and differences between the sexes, are most notable near adolescence. Sexual maturation leads to an adolescent growth spurt and happens at different times in boys and girls and at different times in individuals of either gender.

Front 12

Is chronological age a good indicator of an individual's growth status?

Back 12

Because of timing variability, chronologic age often is not a good indicator of an individual's growth status.

Front 13

What is a way dentists/orthodontists measure biological age?

Back 13

Using cervical vertebrae, which are seen in cephalometric x-rays that are taken to evealuate facial proportions in children who need treatment. The stages in maturation of the cervical vertebrae correlate well with the adolescent grwoth spurt, which is the best time for orthodontic treatment.

Front 14

What could biologic age also be called?

Back 14

Developmental or maturational ages.

Front 15

What are examples of biological age determinants?

Back 15

dental age, height age, intellectual development (IQ)

Front 16

What are two study designs for studying types of growth?

Back 16

(1) Cross-sectional studies and (2) Longitduinal.

Front 17

What are cross-sectional studies?

Back 17

Rather than seeing the same individual over time, data is taken from a gropu of 9-yr-olds, a different group of 10-yr-olds, ect.
It is quicker and easier.

Front 18

What are the downsides to a cross-sectional study?

Back 18

The amount of individual variation is understated. The mean for the group gives a very misleading picture of what happens to any individual.

Front 19

What are longitudinal studies?

Back 19

The same individual is followed over time.

Front 20

What are the benefits of a longitudinal study?

Back 20

It provides more information about individual variation.

Front 21

What are the downsides to the longitudinal studies?

Back 21

It takes a long time and can become quite expensive.

Front 22

List the Growth measurment techniques.

Back 22

(1) Craniometry
(2) Anthropometry
(3) Cephalometric Radiology
(4) Cone-beam CT Superimpositions
(5) Vital Staining
(6) Autoradiography
(7) Implant Radiology
(8) Molecular Techniques

Front 23

What is craniometry?

Back 23

Craniometry is based on measurements of human skulls.

Front 24

What is anthropometry?

Back 24

Anthropometry includes taking measurements on living individuals. Various landmarks on the skull were established by investigators studying skeletal material (soft tissue points overlaying those landmarks can be used to studying living individuals).
Anthropometry produces longitudinal data and therefore shows individual variation much more precisely.

Front 25

What is cephalometric radiology?

Back 25

It uses x-ray pictures of the head and face which provides a way to combine the advantages of carniometry and anthropometry. It allows the direct measurement of the skeleton because the soft tissue thickness can be ignored.

Front 26

What are the disadvantages to cephalometric radiolgy?

Back 26

(1) Exposure to x-rays are required.
(2) Radiograph is a 2-D representation of 3-D structures.

Front 27

What are the benefits of cone-beam CT superimpositions?

Back 27

Image of the head has offered a significant reduction in both cost and radiation.

Front 28

How do cone-beam CT superimpositions differ from cephalometric radiology?

Back 28

Mpw [pssob;e tp si[ero,[pse pm sirface cpmtpirs. amd cjamges betweem sequential 3-D images.

Front 29

What is vital staining?

Back 29

Vital staining uses dyes that are incorporated into bone (or sometimes other tisses) and are injected in animals. Bone that was growing at the time the dye was injected is stained and the amount of growth between the two injections or since the last injection can be seen.

Front 30

What is autoradiography?

Back 30

Autoradiography is based on causing tissues to take their own pictures. Radioactively labeled substances are injected, tissue specimens are prepared, and when photraphic film is exposed by placing it over the tissue specimen in the dark, the location of radioactive materials in the tissue is revealed as radiation activates silver grains in the film layer.

Front 31

What is implant radiology?

Back 31

Implant radiology is based on visualizing metal pins placed in the skeleton.

Front 32

What is an example of molecular techniques?

Back 32

Genetic information carried by plasmids can be injected into the nucleus of a mouse egg, which is then implanted into a pseudopregant mosue. These genetically altered mice can be examined for morphologic differences.