growth and development Flashcards
what does growth indicated
Change most often associated with increase
what does Development mean
New capabilities, bigger and better, with possibility of some cost
-complexity and decrease in potentiality
what is a growth pattern
a complex set of proportional relationships, with some growth being larger and smaller than others
what type of pattern is pattern in growth
A higher level patter, with predicable changes
what is a pattern
changes in proportion over the course of time
what is the cephalocaudal pattern of growth
craniofacial structures grow earlier and structures away from head grow more to chatch up
how does the skull grow
more growth in the face than in the cranium. Cranium grows faster than face first then slows as the face speeds up
parts of the face that grow farther from the cranium grow the slowest
what part of the face grows the most postnataly
The mandibule
what does it mean when doing data and points do not cluster such like a bell shaped curve
Not a normal distribution
what is 1 std dev
67% of the population
what is 2 std dev
95% of the population
what is 3 std dev
99% of the population
what does a median value correspond to
2nd quartil
what is the inter-quartile range
Measure of variation reported with the median value
how are growth chars expressed
In percentile, comparing height and weight to peers over time
organization of growth charts
line is percentile
x is time
y is height/weight
what is the percentile for normal kids
3rd and 97th percentile
how does growth charts show abnormalties
crossing over in percentiles over the ages
when are differences in timing of growth most apparent
Near adolscence
what causes adolescent growth spurt
SExual maturation
when do boys and girls have te growth spurt
girls two years before boys
why might a person cross percentiles in growth, but not be a problem
if a person matures unusually late or early, they’ll cross percentiles
why is chronologic age not a good indicator of an individual growth status
BEcause of timing variability
how is age measured biologically
In terms of progress towards achievement of certain development markers
how to measure biologic age
maturation of cervical vertebrae
what does the stages in maturation of the cervical vertebrae correlate well with
Adolescent growth spurt
when is the best time for ortho
Adolescent growth spurt
stage 2 age
indicates that peak growth at adolsecence is still a year or so ahead
stage 3 age
less then one year till peak growth
stage 4,5, and 6
increasing distances beyond peak growth
best stage to do ortho
stage 3
other name for biologic age
Developmental or maturation ages
cross sectional studies
TAken from different groups at different points, instead of tracing one person
pros and cons of cross sectional
easy, individual variation though is a problem
longitudinal studies
Same individual is folowed over time
what is the distance vs velocity in longitudinal growth
distance is overal growth
Velocity is how fast the growth occured
basic measurement techniques for physical growth
Craniometry Anthropometry Cephalometric radiography 3D radiography (computed tomography)
WHAT IS CRANIOMETRY
based on the measurement of the skull
what is Anthropometry
Measurements on living individuals, using soft tissue landmarks
source of error in anthropometry
varying soft tissue thickness
use of anthropometry today
Estabilish facial proportions, for planning ortho treatment
what is cephalomtric radiology
USing X-rays of head and face to provide a way to combine the advantages of cranometry and thropometry
Pros and cons of cephalometric radiology
Direcet measurement of the skeleton, but still can measure soft tissue
needs proper possitioning
2D
exposure to X-rays
pros and cons of axial computed tomography
reconstruct facial images in 3D
expensive
large radiation dose
benifit of Cone beam CT
less radiation
cost less
problem with cone beam CT
not as accurate as Axial Ct, but still good
why superimpose CT scans
tracing based on identified landmarks to show growth
why is the marker technique mostly used in animals
Can be destructive
techniques for markers
Vital staining
Autoradiography
Cephalometric superimposition on Implants
Molecular bio
what is Vital staining
Dyes that are incorporated into bone are injected into animal and amount of growth between 2 injection or since the last injection can be seen
what dye is used to stain bone
Alizzarian
what is autoradiography
RAdioactively labeled substances are injected, tissue specimens are prepared, and when photographic film is exposed and the location of radioactive materials in the tissue is revealed
benifit of radioactive labeleing
Any substance can be turned intot he equivalent vital stain
what is implant radiology
Based onvisualizing metal pins placed in the skelton and using them as perminant markers, since they show up on x-rays
what was used to understand jaw growth patterns
Implant Radiology
how does the JAw grow
bone was added to the posterior surface of the ramus and condylar and coronoid processes
removed bone from the gonial angle area
molecularily measuring growth
genetic info by plasmids injected into mice
we see how the mice now are different morphologically
