in class notes Flashcards
what does the flat bone of the cranial vault come from
from periosteal activitiy at the inner, outer, and fontanellies
what does modeling of the cranial vault lead to
Changes in size and shape
how does the cranial base growth
endochondral-synchrosis pushes bones apart to lengthen the base of the skull
what causes the maxilla to grow down and widden
Soft tissue (functional theory)
where is bone added and removed to cause maxillary growth
Resorbed in the front and added in the back
how does the mandible form
Extramembranous in association with meckel’s cartilage
how does the mandible grow
resportion in front of ramus and deposited behind the remus
in the body, where do things grow first
Things closest to brain grow first
What separates girls and boys growth spurts
2 years
why do guys grow more in their growth spurt
their’s is longer
how does tooth eruption affect the bone
Brings the alveolar bone with it
what is the affect of having implants too early
Late gowth can affect how implants change with time
where should normal people be found within the growth curve
within 2 standard deviations
shouldn’t move all around too
at what age do you have all your baby teeth
30 months
what happens if you can’t resorb baby teeth
may need to have them extracted
what is done to close space in the mandible naturally
the molars will move forward, but won’t affect anything really mesial to the canine due to the long roots
does unilateral cross bites tend to hang around
No, generally fixed to become a posterior cross bite
how can we use the leeway space to reduce incisor crowding
Hold the 1st molars back and since the premolars are smaller than the teeth they replace, extra room can be opened for erupting anterior teeth
what is the E space
The space difference between the primary second molar and the permanant first molar
how large is the E space
1/3 the leeway space
are primary or permant teeth whiter
Primary
what extra width does each slipped contact add
1mm (unless very slipped)
mild crowding is how many mm
1-2.99mm
medium crowding
3-5.99mm
severe crowding size
6mm
what causes the irregularity increase between childhood and youthq
Jaw growth (NOT 3rd molars)
what allows a decrease in crowding as your permant teeth come in
incisors erupt labially
canines erupt distal
development/primate spaces
are babies class I, class II, or class III
class II
when does late dentiton begin
when you get premolars
what is a mesial step
when max 1st molar is behind the mandibular first molar
what is a flush plane
max 1st molar nad mandibular first molar are equal
what is a distal step
when the max 1st molar is infront of the mandibular first
what does a mesial step turn into
class I and Class III
what does a flush plane turn into
Class I and Class II
what does a distal step turn into
Class II
what happens to early mild class II relationships
tuend to decrease as you get older due to late mandibular growth
what happens to early mild class III relationships
tends to increase as you get older due to mandibular growth
what classification do asians tend to have
class III
what classification do whites tend to have
Class II
what calssification do blacks tend to have
Class III and open bite
how does deep bite change with age
decreases with growth
what is the order of jaw growth
transverse stops first
AP stops second
Verticle stops last
what kind of malocclustion does late mandibular growth lead to
Cross bite
what is tooth gemination
when two crowns come from one root
what is the eqalibrium theory of location
soft tissue+ tongue balance each othe out
how does mouth breathing affect oral development
no tongue on top of teeth so palate shrinks
how long must pressure be applied to teeth to cause a change
6 hours
what is bimaxillary protrustion
when both jaws protrude forward
what kind of molar classification must exist to be a deep over bite
can never be class III
what does it mean when ANB is negative
Class III
what does it mean when ANB is possitive
class II
what does it mean to increase incisal angle
proclined
what does it mean to decrease incisal angle
Reclined
how do proclined incisors affect the soft tissue
gingival recession
Protruding lips
how do reclined incisors affect the soft tissue
retruded lips
how does crowding affect incisor angle
Proclined teeth
what is the E line
Tip of the nose to the tip of the chin
how sould the lips relate to the E line
upper is 4mm behind
lower is 2mm behind
size of the lower premolars and cnaines
7mm each
size of the maxillary canines
8mm each
how wide of maxillary incisors
8-9 for centrals
6-7 for laterals
width of mandibular incisors
5-6mm
how much space can exist between lips for it not to be a problem
4mm without strain
when should you do surgery for ortho
Done first
what is class II devision 1 mean
Increased overjet
class II devision 2
increase over bite
why can’t you move implants
no pdl
where do osteoclasts come from
bone marrow (not the PDL)
what is the clinically fastest way to move a tooth
Tipping
how can someone get translational movement
use of an arch wise
what are the causes of root resorption
dilaceration Root contract with lingual cortical bone Geneetics Conical root previous root resorption Trauma
what should you do to check for root resorption
Take a Pan after 9 months of treatment
what kind of anchor is a TAD
Absolute anchor
maximum anchorate
Posterior stays put and pulls anterior backwards
what is minimum achorate
anterior stays put and pulls posterior forward
what is assisted tooth movement
Removal of cortical bone to accelerate tooth movement
how do NASAIDS affect tooth movement
Slow it down, cuz inflammation is needed
can you change mandibular growth
No, can only accelearte it at the condyl
what is the most unstable form of ortho movement
Palatal expander
what does Rapid palatal expanders do to the teeth
leads to a diastima that should close after time
what does head gear do
Restrains the maxilla from down and forward movement by pulling on teeth
what is the ideal force on teeth
50-200 g
what is the ideal force on headgear
250-500 g
what is the expansion rate for Rapid palatal expanders
2-4 tuns a day (.25 mm per turn)
what is the expansion rate for slow palatal expanders
1 turn every two days (.25mm per turn)
when should you do palatal expansion
before 15 years old
what are the phases of distraction osteogenesis
latency
Distraction
consilidation
Remodeling
what is SARPE
surgically assisted rapid palatal expanders (done on adults to cut open surutre)
what deterines the center of resistance
surrounding tissue
what is deformability
Ability of wire to be bent perminantly
what is the deformability of large vs small wire
smaller is easier to bend
smaller has a larger range
what kind of wire is used in the finishing satage of rotho
heavy wire to maintain treatment outcome with lots of bends to make it more flexible
what is a 3rd order bend
buccal torque/rotation (inclination)
what is a 1st order bend
Buccal tranlation(push teeth in and out)
what is a second order bend
angulation/vertical (M-D tipping)
what kind of curve measures the extrinisic
Force-deflection
what kind of curve measures the intrinsic
Stress strain
is a circle or a rectangle more stiff
rectangle is more stiff
what is the proptional limit
the limit to wear an increase in force leads to the same amount of deflection
where is the yield limit
the point at which .1% deflection is no longer proportional to the aount of force in the bend
- does not return to its original size
what is springback
The ability to return to its original shape
what is range
The amount a wire can be bent without permanent deformation
what is strength
stiffness x range
how does increasing size change stregth, sprininess, and range
decrease strength
decrease springiness
decrease range
how does increasing length change stregnth, springiness, and range
decrease strength
increase springiness
increase range
HOW DO YOU cange the center of reisistance
change via root resorption (moves coronally)
changes via bone loss (moves apically)
how do you change the center of rotation
by application of forces
what is a moment
The tendency to rotate
what is the equation for a moment
Grams x mm distance perpandicular to the line of action through the center of resistance
pros of removable ortho
Clean
asthetics
cons of removable ortho
Loses
patient compliance
tipping only good force
how can removable ortho induce tipping
holly appliacnce
why usea functional appliance
Change growth
how can we try nd stimulate mandibular growth
Herbs appliance
how can we try and stop mandibular growth
headgear
what are some removable fucntional apliances
fimback
headgear
activators
what are some fixed functional appliances
herbs
forsus
Mara
why use an anterior bite block
to fix a deep bite
why use a posterior bite block
causes extrusion of anterior teeth
pros of fixed appliances
more relaible
more foces
cons of fixed appliances
dirty
what did angle invent for ortho
found that is wire is situated facial lingually you can get more contol
what is the roll of a begg’s appliace
Used to upright roots after tipping
what did andrew contribute to ortho
adjusted brackets (don’t bend arch wire)
what are the expansion appliances
Hyrax
W-arch
Frankol (tissue born appliance to do expansion)
Quad helix
why use a power chain
pull all the teeth together
why use a lip bumper
Pull the lower teeth forward
why use a transpalatal arch
uses a wire across the arch to stop side effects and stop tipping during expansion
why use a lower lingual holding arch
space maintainers
why use a tongue crib
tells tongue to go back into the mouth
