Orthodontics II Flashcards
DENTAL ARCH MEASUREMENTS nArch \_\_\_\_ n Arch \_\_\_\_ n Arch \_\_\_\_ n Arch \_\_\_\_ (Height)
• When we talk about dimensional measurements of the dental arch, we think about primarily arch circumference which is the measurement of the ____ and ____ of the arch itself.
length width circumference depth size shape
Arch Length
INTERCANINE DISTANCE
When we talk about measurements of arch length we talk about this measurement.
• Arch length- is the ____ line from the most anterior tooth in the mouth to the most
posterior tooth
◦ In the primary dentition- The most posterior tooth is the distal aspects of the
primary second molar.
◦ In a mixed dentition or permanent dentition- were talking about that same anterior position which is tangent across the ant surface of the teeth to the most posterior tooth which is the distal aspect of second premolar or the mesial aspect of the adult molar.
tangent
Arch Length Changes From Primary to Permanent
- increase?
- decrease?
In some respects, its arch length is going to stay the same!
• We see more consistencies in arch length in the ____ arch
• But actually for both arches, we see a ____ in the arch length measurements
◦ Decrease is seem more substantially in the ____ and only slightly in the
maxillary
• Therefore, we will have ____ space for teeth as we progress from a full
complement of primary teeth to a full complement of permanent teeth.
maxillary
decrease
mandible
less
Arch length
Mandibular, girls
• When looking at these graphs, its important to note the axis
◦ X axis- Age in ____
◦ Y axis- Changes in ____ (mm)
• These arch length changes will be ____ specific and ____ specific.
• We will see subtle changes in regards to gender specific issues. Like for most things
we’ve talked about in dental and growth and development so far.
• However we will see more dramatic difference when we compare changes in the max arch length vs mand arch
years
arch length measurement
arch
gender
Transition from Full Primary to Full Permanent Dentition
n 3 Stages of Development
n ____ Dentition
n ____ Period
n ____ Dentition
early mixed
intertransitional
late mixed
Early mixed dentition
• In the early mixed dentition we see a very slight ____ of our arch length measurement.
◦ Primary dentition - posterior tooth Is the ____ in the primary dentition.
◦ Mixed dentition- posterior tooth is the messiah aspect of the ____.
we originally see some early loss of spaces as we decrease from 25 to about 24. That initial downwards slope and loss of arch length is due to closure of ____.
The we see the emergence of the ____
◦ Remember this is the same sequence that we talked about last time.
◦ M1- perm first molar, I1- perm central , I2-perm lateral.
‣ In palmer notation M1, I1, I2 is 6,1,2 respectively
We see a slight slight uptick as we see the emergence of the incisors.
decease 2nd molar perm first molar primate space perm first molar
PRIMATE SPACE
n LOCATION
n TIMING of CLOSURE
There’s 2 main spaces that we talk about when we measure arch length differences.
A. Primate space- a ____ space closure or space loss
B. Loss of leeway space- ____ space closure or space loss
• These are important concepts to understand because these are typical questions that would be asked on the orthodontist/pedo section of the boards!
• So this is the substantial part of the dimensional change of the arch and they’re important spaces to understand.
• Where these spaces are ____ are gonna be important, the ____ and amount of closure is important to know as well.
minimal
major
located
timing
PRIMATE SPACE
n LOCATION
nMaxillary Arch > Between ____
nMandibular Arch > Between ____
• Primate space in the maxillary arch is located ____ to the primary canine.
• Primate space in the mandible is located ____ to the primary canine
primary lateral incisor and canine
primary canine and primary first molar
mesial
distal
n TIMING OF CLOSUREà Upon eruption of permanent ____ (especially mandibular)
◦ So when we see ____ emerge, we see the closure of primate space
Why would primate space be more affected in the mandibular arch than the maxillary arch?
• Yes, the mandibular teeth erupt first but what about the locations of the molar
related to the space?
◦ Its closer to the ____!
• So if you have a tooth emerging from the ____ aspect of the dentition the mandibular arch, the primate space is gonna be more directly affected than max arch primate space.
◦ Because its actually closer to the emergence of the permanent teeth.
◦ We have more closure of the primate space in ____ and as opposed to the max.
◦ Most of the primate space is maintained for the most part in the max arch.
There is some closure in the maxillary but it is not as substantial as the mandibular
first molars 6 space distal mandibular
Arch Length ____
Primary to Permanent
n Closure of ____
n Closure of Leeway Space
decrease
primate space
Transition from Primary to Permanent
n 3 Stages of Development
n ____ Dentition
n ____ Period
n ____ Dentition
- Early mixed dentition is from age ____.
- Intertransitional period is from age ____.
- Late mixed is ____ and a little beyond
early mixed intertransitional late mixed 6 to 8 8 to 10 10-12
Transition from Primary to Permanent
What occurs in this inter transitional period from a tooth emergece perspective?
• As we discussed the other day, during an early mixed dentition:
◦ We started with 20 primary teeth
◦ We see the emergence of the ____.
‣ Remember the early stage of mixed dentition we have a complement of 20 primary teeth with ____ adult teeth!
‣ Therefore we end up with a total of ____ teeth.
How many teeth do we have at the end stage of the early mixed dentition?
• ____ is correct! But what is our ratio?
• We still have the same complement of teeth but the ratio will be different 50% adult and 50%
primary = ____ primary and ____ permanent
◦ At the latest stage of the early mixed dentition we are gonna exfoliate our primary central and primary laterals in both the max and mandibular arch.
◦ So we’re gonna see the emergence of perm laterals, perm centrals perm at this point.
perm first molars
4
24
24
12
12
Intertransitional Period
What happens in the intertransitional period (age 8-10) from a tooth emergence perspective?
• There are no ____ changes.
• Theres a lot evolving in terms of tooth formation underlying the primary teeth.
• But purely looking at ____ pattern, we don’t see any changes. We see the emergence of 6, 1, 2, in the early mixed dentition
• In intertransitional phase (sometimes referred to middle mix transition)
◦ We see no ____ changes
◦ We see emergence in mand arch of perm first molars, perm central, perm lateral incisor. this plateau here is the inter transitional period
dental emergence
dental emergence
dental emergence
Transition from Primary to Permanent
n 3 Stages of Development
n Early Mixed Dentition
n Intertransitional Period
n Late Mixed Dentition
Then we move on in a late mixed dentition in mandibular arch
Whats the first event that occurs in the late mixed dentition in the Mandibular arch?
1. We see loss of ____
2. Emergence of ____
primary canine
perm canine
Late Mixed Dentition
• Quiz question: what would our first event be in the mixed late dentition in the max arch? ◦ Its ____. Remember the sequence is going to be different.
◦ The sequence in mixed late dentition is ____ in (palmer notation) for mandibular
◦ And ____ in maxillary
• We see emergence of perm canine and first second premolar.
• Dimensionally, we’ve gone from about 24 mm to the emergence of our perm second molar to about ____ mm.
• We lose ____ space. Which is the Mesial-Distance distance between the primary molars and PM
first premolar 3457 4537 22.5 leeway
LEEWAY SPACE
nLOCATION > Differential in ____ size between primary molars and premolars (possibly canines)
Of all of the teeth, if we include canines, primary first molar, primary 2nd molars, and compare max to Mandibular teeth. Which single tooth do you think contributes the most to leeway space?
◦ Answer: ____
◦ Think about the size and shape of primary 2nd molar.
‣ Remember from tooth anatomy, the primary second molar is almost as large MD as a perm first molar.
‣ If you picture the size and shape of a larger primary molar tooth and the second premolar substituting for that space, theres a substantial difference between the size and shape MD.
◦ Yes, a single primary 2nd molar will contribute the most to leeway space. This is why we have more leeway space in ____ than the max arch.
mesiodistal
mand second molar
mandibular
LEEWAY SPACE
nTIMING OF CLOSURE > Closes by loss of ____ (especially 2nd molar) upon eruption of ____, mostly from a ____ direction
primary molars
premolars
distal
Arch Length DECREASE Primary to Permanent
n Closure of Primate Spaces
n Closure of Leeway Spaces
- Closure of leeway space - major decrease
A. Reminder again this is from the emergence of the ____, first PM, 2nd PM, ultimately to the perm first molar - In the graph we can see that we started out at 25.5 mm and ended up ended up at ____ mm.
A. So we have quite a substantial closure or loss of arch length from that transition from primary teeth into perm teeth
perm canine
23
Changes in Arch Length Primary to Permanent Dentition
nEarly Mesial Shift =Closure of ____
nLate Mesial Shift =Closure of ____
primate space
leeway space
“Maintenance of the ____ is sufficient to align all of the permanent teeth within the arch in seventy percent of children.”
This means that we could conserve leeway space!
- If we start ____ before we lose primary second molars, we can preserve the leeway space
- We may be able to correct crowding issues using the extra posterior space to unravel anterior crowded and thus avoid having to consider extracting perm teeth
We try to do as much as we can to avoid ____ extractions.
◦ Sometimes its necessary but if we can preserve leeway space that gives us one advantage in that non extraction vs ext mode of treatment. Especially when we transition from late mixed dent to perm dentition. Which is for the most part around the time we usually begin a comp tx phase or what we called a stage/ phase 2 tx.
primary second molar
treatment
PM
ARCH LENGTH CHANGES
n ____ SPECIFIC
n ____ SPECIFIC
ARCH
GENDER
Arch Length Difference Mandibular; Girls v. Boys
- There are changes are really ____.
- The graphs are ____
- The biggest difference has to do with the maxillary as compared to the ____ graph. ◦ The reason why is because we see a lesser close of ____
subtle
analogies
mandibular
primate space
Arch Length Difference
Maxillary; girls v boys
• The biggest difference has to do with the max as compared to the Mandi graph.
• The reason why is because we see a lesser closure of ____ as upon the emergence of ____
• We see a larger uptick as we see emergence of perm Central and perm lateral incisors. And the middle
part of the mixed dentition is the inter transitional period. And then a loss of leeway space.
• We have our leeway space closure and the sequence of mergence is difference where instead we see 345 canine followed by 1st 2nd PM. In the max arch we see first PM, 2nd PM, canine and followed by
emergence of the perm 2nd molar.
primate space
perm first molar
Arch length difference
Maxillary; girls v boys
Why do we see this larger uptick when we have primate space closure and then really its off set substantially by increased arch length as we see emergence of perm central and perm lateral incisors.
Why does this occur?
We talked about this previously on weds. The eruption pattern of max incisors as opposed to Mandi incisors. Do yrhy have a tendency to erupt in the max arch in an identical spot to the psi incisors or do they have a tendency to erupt ina. More labial position compared to the primary incisors?
• ____. If you picture our arch length measurement from the most ant tooth to the most D aspect of the primary second molar or the M aspect to the second first molar. If you have incisors that will emerge slightly labial to the primary teeth they’re replacing this will actually ____ our arch length measurement.
Then we have our inter transitional period. And we have a lesser loss of space because again the difference in size between our primary molars compared to the PM in the max arch is ____ awn what we had in the mandibular arch
Overall is our net difference lesser or greater than the max arch?
• Its ____, substantially lesser. Started out with 28mm with our arch length measurement and we ended
about ____ so we have substantial amount of net difference from beginning to end in Mandi arch as
labial increase lesser lesser 27.5
Arch length difference
Max. v. mand; boys
• When we talk about our differences when we look at the graph for boys
◦ Maxillary- started at ____ mm and ended at ____
◦ Mandibular- started at ____ and ended at ____
• In maxillary graph- maxillary graph where we see the ____ of the incisors,
◦ which is going to offset our loss of ____
• In mandibular arch - we don’t have much labiality of the incisors because of the ____ pattern.
◦ so the loss of primate space added to our loss of leeway space isn’t really offset by much.
29 28 25.5 23 labiality leeway space eruption
DENTAL ARCH
n Arch Length
n Arch Width
n Arch Circumference n Arch Depth (Height)
With regard to arch width, we talk about our ____ changes, and our ____ differences.
transverse
intercanine width
Development of the Dental Arch
Arch Breadth
- Most times when we’re talking about transverse measurements, we’re talking about measurements between ____ of the canine transversely.
- Sometimes we look at midarch changes, sometimes we look at intermolar changes, but our main focus is just looking at our intercanine changes.
cusp tip to cusp tip
Intercanine Distance Mandibular; Girls
Intercanine Distance Mandibular; Girls
If we look at our graphs, we see that in a similar way when we talked about arch length changes, when we measure our intercanine distance, we see our emergence in early mixed dentition of our permanent first molar, our permanent central, our permanent central incisor, and our next tooth that is going to be affected, the emergence of the permanent canine.
We see quite a bit of an uptick, so we see quite a bit of an increased width measurement during that ____. Once we get to a certain point where we see again the primary canines that are really in essence expanding out up to this point, when we see the ____ emerge in, we then see this plateau out.
So we have our early stage of mixed dentition at age ____, as we get to about age ____, a time of the emergence of the ____, we see our intercanine width increase over that span and then thusly, the permanent canine emerges into that same position of the primary canine.
early mixed dentition permanent canine 6 10 permanent canine
Intercanine Distance
maxillary; girls
- Another difference, like we talked about, differences compared to gender specific differences, but much greater differences, looking at the graphs, comparing ____ to mandibular arches.
- We see the same upward tick, upward slope, when we see the emergence of the permanent molar, central and later incisors, and permanent canine, and then we continue to see an upward tick of intercanine distance because for similar reasons, the maxillary canines have a tendency to emerge out in a more ____ position.
- So we have a ____ upward slope upon emergence of the canines, so canine width still increases a bit over time as we progress to age ____.
- When we talk about our arch specific differences, in the mandibular arch, we see emergence of our, in our early mixed dentition, molar, central, lateral, and then basically the canine emerges into the ____ of the primary.
- In the maxillary arch, we see the same upwards slope upon emergence of canine, but then we see a ____ upward slope as we still see some increase of intercanine width.
maxillary
labial
second
12
position
Development of the Dental Arch
Arch Circumference
- When we talk about arch circumference, we’re talking about really the measurement of the ____ itself of the arch.
- So we’re looking through the posterior contact points, through premolars or primary molars, across the cusp tips of canines, across the incisors, back to the opposite side.
- And again, this is the essence of considering our measurement of our arch circumference that we have available vs. our arch circumference that we have required.
perimeter
SPACE ANALYSIS
n Arch circumference ____
n Methods of evaluation n Permanent dentition n \_\_\_\_ tooth measurement n Mixed dentition n \_\_\_\_ analysis n \_\_\_\_ n \_\_\_\_-Johnson
- When we talk about our arch circumference available, we’re talking about how much space we ____ have on the arch itself.
- When we talk about arch circumference required, it’s really the sum total of all ____ teeth that we’re trying to fit from second premolar to second premolar.
available v. required mesiodistal radiographic moyers tanaka physically 10
Space Analysis
We will consider a space analysis, which is an integral part of ____. It is much easier to do in ____ planning than mixed dentition.
treatment planning
permanent planning
Space Analysis
• Our space available is a measurement of the ____ of the arch itself.
• Our space required is a ____ measurement of the said teeth, and really the arch
circumference required is the sum total of all the teeth that we have to fit in place.
• If our arch circumference required, the measurement of the sum total of the teeth themselves, is ____ than the arch circumference available, the measurement of the dental arch, then we
have issues of ____. If we have the converse of that, if arch circumference available is ____ than the sum total of the mesiodistal measurements of the teeth, then we have ____ again.
It gives us the ability to ____ how much crowding or how much spacing we have per arch. If we just look at a patient clinically and say these teeth look crowded, how much crowding is that actually? Is it 2 mm, 5 mm, is it 7-10 mm of crowding? With this method, we are able to quantify how much crowding or how much spacing we are dealing with as part of our treatment planning process in orthodontic treatment.
circumference mesiodistal greater crowding larger space
quantify
- One thing you have to contend with, especially the arch circumference available method, is that you have to consider the position of the ____.
- If we use that method of going through contact points of posterior teeth, across cusp tips of canines and incisors, if teeth are very flared forward, that will ____ the measurement.
- If they are retroclined and recumbent, that is going to ____ that measurement.
• If these teeth were at their proper inclinations like in the darker pink picture, that is of
course going to change the actual numeric value of the differential between the arch
circumference available and required.
• ____ is an important tool in part of the space analysis to determine these positions of the incisors and seeing how they’re affecting the measurement values of that differential.
incisors
increase
decrease
cephalometrics
Space analysis methodology
n Direct (\_\_\_\_ measurement) n Indirect (\_\_\_\_ tables)
With the methodology of space analysis, we have a direct tooth size vs. arch size measurement, or we can use an indirect method like radiographic or prediction tables.
tooth size v arch size
radiographic/prediction
Space Analysis (mixed dentition)
Radiographic method
(primary molar/primary molar (x-ray)) = (permanent PM/permanent PM (x-ray))
- If we have a full complement of permanent teeth, it’s really a measurement on a cast of the ____ itself, vs the ____ of the teeth that we measure with calipers.
- If we don’t have a full complement of permanent teeth and we still have primary molar teeth available, we have to address the difference in magnification from the ____ to the actual tooth.
- How we do that is to measure the tooth, the primary molar on the cast, we’d measure radiographically the tooth in question, the premolar tooth replacing the primary molar tooth, and then set up a simple algebraic equation to correct the ____ difference from the radiograph to the cast.
- It would give us a more ____ measurement of that mesiodistal width of that premolar.
dental arch
sum total
radiograph
magnification
accurate
Space Analysis
Tanaka-Johnson (SIMPLIFIED)
____ width of the ____ permanent incisors
+____ mm = estimated width of canines and premolars - mandibular
+____ mm = estimated width of canines and premolars - maxillary
mesiodistal
lower four
21
22
Space Analysis
Moyers tables
• A better, more ____ method is to use these prediction tables, like Moyer’s
◦ Use the ____ widths of the ____ permanent ____
to predict unerupted values of permanent ____, and first and second premolars,
both in the ____.
◦ Moyers tables are set in ____ specific and ____ specific.
detailed mesiodistal mandibular central and lateral incisors canines maxillary and mandibular gender arch
DENTAL ARCH
- Arch Depth (height)
• If we place that implant very early, such as at age 14, what will the implant look like at age 18 and the twenties?
◦ The implant will look more ____, almost like an ankylosed tooth, because we will still see some increase of ____ development adjacent to where the implant will be placed.
◦ If we have that implant placed at 14 and we see some continued alveolar development, that tooth will have a more submerged position compared to the adjacent teeth. It is best to consider those alveolar changes over time and considering waiting for specific circumstances like implant placement.
submerged
alveolar
What practitioners, pediatric dentist do, is look at the most ____ aspect of the teeth.
◦ Instead of looking at cuspal relationships like we did when discussing angle
classification of molar relationships, we’re looking at the distal aspect of the most posterior teeth, namely the primary second molars.
Most of the time, which have the greatest tendency to become a class I, we have a ____– the distal aspect of the maxillary molar aligns exactly in a flush terminal plane with the distal aspect of the ____.
distal
flush terminal plane
primary secondary molar
PRIMARY MOLAR RELATIONSHIP
n ____
n ____
n ____
• Our 3 considerations are distal step, flush terminal plane, and mesial step.
• It’s not as easily defined as an angle classification, because there is still a big dynamic of what has to happen from consideration of our transition from primary molar to mixed dentition into full emergence of permanent teeth.
distal step
flush terminal plane
mesial step
Primary to Permanent Class I, II, or III
- With regard to that, we now talk about percentages of if a patient presents with a distal step, which means the mandibular tooth is in a more ____ position in relationship with the posterior position of the maxillary tooth, a ____ terminal plane
- or a mesial step where the mandibular tooth is slightly ____ of the distal aspect of the maxillary tooth…
distal
flush
mesial
PRIMARY MOLAR RELATIONSHIP
nDistal Step > Predisposes ____
n Flush Terminal Plane
n Mesial Step
… it has probabilities of developing into class I, class II, class III.
• Distal step, in many cases, predisposes a class II relationship as things progress.
• A flush terminal plane, studies show, mostly evolve into ____ in 56% of cases, or
sometimes a ____ (44%).
• A mesial step can progress in a similar way when we talked about flush terminal plane,
into a ____ or ____.
class II class I class II
class III class I
Transition from
Primary to Early Mixed Dentition
- When we talk about the rationale for this, why a flush terminal plane many times progresses into a class I, is really because of that differential that we have of the primary second molars.
- If we have larger mandibular primary second molars, if these teeth are in a flush terminal plane, from the outset, and we have a large mandibular primary molar, once we exfoliate those two primary molars, both maxillary and mandibular, we see more mesialization of the permanent first molar in the ____ than the maxillary.
- If we have more mesial drift of the mandibalar first molar, where these teeth are in a more end to end position in the posterior, and that flush terminal plane creates that, we have this tooth evolve a bit further. Once we lose the primary molar, we see this tooth, the permanent first molar, ____ a bit ahead, thus developing into that ____.
mandibular
step
class I
Transition from Late Mixed to Permanent Dentition
If we lose primary molars because of the larger size of the primary second molar in the mandibular arch, we have more loss of ____ in the mandibular arch, if we don’t preserve it, thus developing into that ____ relationship.
leeway space class I
DEVELOPMENT OF THE DENTITION
Changes that occur in the mandible and the maxilla to provide adequate ____ and bone for the teeth
space
- … in the primary dentition, we progress from just a set of 20 primary teeth.
- Our first step in the developmental process when we develop from primary to permanent teeth, is the emergence of the permanent ____.
- Like we talked about at that time, we have a complement of ____ teeth, 20 primary teeth followed by 4 adult teeth, and the other thing we discussed is the difference between successional teeth and accessional teeth.
first molars
24
• Successional teeth are permanent teeth that replace primary teeth
◦ so same complement of primary incisors, primary canines, followed by emergence of
permanent ____ and permanent ____.
• Again, primary molars are replaced by premolars,
◦ and these are all successional teeth in a normal state of affairs.
◦ Those 20 primary teeth will be replaced by 20 permanent teeth, so that gives us our
differential of 20
• Considering we start with 20 primary teeth and should end, with proper emergence of third molars, with ____ teeth.
• Those remaining 12 teeth should come from ____ eruption, or the fact that permanent teeth like these all permanent molars, will emerge distal to that last toot that is emerged in.
• That gives us the greater number of permanent teeth as we have to primary teeth, basically set by the addition of the accessional teeth
incisors
canines
32
accessional
Our first event that occurs is emergence of the permanent ____ Second is exfoliation of primary ____
Most times the trend will follow where ____ teeth will emerge ahead of max teeth
◦ So first primary teeth are primary mandibular ____, followed by emergence of permanent lateral incisors…
first molar
incisors
central incisors
• then we see the emergence of the same complementary maxillary teeth, so we lose maxillary primary incisors, followed by emergence of permanent incisors, thus we lose primary mandibular ____…
lateral incisors
- …we see the emergence of our permanent ____, both max and mandibular, both centrals and laterals and again at this age, where are we?
- These dynamic changes in early mixed dentition, where we see emergence of 612, occur from about age ____ to age ____.
- Then again from age ____ to age ____ from tooth emergence perspectives, ____ changes.
incisors 6 8 8 10 no
…our emergence of our permanent mandibular canine to substitute for our mandibular primary canine, and our first event in our ____ dentition, and then we see the…
…emergence of our maxillary ____, and again, followed by mandibular premolar.
late mixed
first premolar
• Thusly followed by exfoliation of our primary ____,
• The last event that would normally occur in our late mixed dentition, is
exfoliation of our ____ before we see emergence.
• The last primary tooth to exfoliate should normally be our maxillary primary canine.
And thus we see emergence of our adult teeth that are successional teeth, then followed by our ____ teeth to emerge in, and then if there is enough space for our ____ to come in.
second molars
maxillary primary canine
adult
third molars
Development of the dentition
Prior to age 12 years, changes provide space for:
- ____
- 1s, 2s, 3s, 4s, 5s
Age 12 years: \_\_\_\_ Age 18 (+) years: \_\_\_\_
- Prior to 12 years of age, arch space requires primary dentition followed by emergence of adult teeth to replace these primary teeth, 1’s, 2’s, 3’s, 4’s, and 5’s, in the areas of the diphont dentition.
- Then at age 12, we see emergence of the 7’s, and at age 18 and older, if there’s sufficient space, we see emergence of third molars.
primary dentition
7s
8s
Individual tooth size is fixed at a ____
Variable:
____ change
very early age
arch
changes in dental arch are ____
main difference:
____ of change
similar
magnitude
There is an integral relationship between ____ of teeth, vs. the ____ of the dental arch.
size and position
size and shape
development of the dentition
Interdental spaces, including primate spaces, can compensate to an extent for ____ between primary and permanent teeth (mainly incisors)
Importance of ratio: ____ tooth size
- When we have problems such as crowding and spacing, we have an insufficiency as far as the size and shape of the dental arch vs the size and shape of teeth that must be accommodated.
- The most important thing is to remember the interdental spaces, as well as primate spaces, can ____ to an extent, the discrepancy between primary and permanent teeth, mainly the ____.
- Not all primary teeth are going to be smaller in size than adult teeth that replace them. That is very true of maxillary and mandibular ____ and canines, but certain teeth like our primary molars, primary first and second molars, very often are replaced by teeth that are ____ in size.
- While it is true that larger teeth replace smaller teeth in the ____ part of the dentition, but in the posterior part of the dentition, most times the primary molar teeth are much ____ in size than the premolar teeth that replace them.
- The importance of that ratio is again that primary vs. permanent tooth size
tooth size discrepancy
primary vs permanent
compensate
incisors
incisors
smaller
anterior
larger
Development of the Dentition
Most dimensional changes in the dental arches occur during the time of ____ of the teeth
Indication that no significant ____ growth mechanism for the dental arch exists
- If at age 3, there are constricted arch issues or at age 8 with posterior cross bites and blocked out laterals, that will be exactly the same even though the patient has significant max and mandibular growth potential.
- Where those teeth are located in the arch will be identical through growth, even if we don’t consider conservation of leeway space like Gianelli suggested, we will have even ____ space when the patient transitions into late mixed dentition and into early aspect of full permanent dentition.
- Such issues are much better treated at an ____ age vs waiting for a patient to get older, even though there is substantial growth potential left.
emergence or exfoliation
spontangeous
less
earlier
• When we see the emergence of our permanent first molars, we see ____.
◦ The maxillary primate space is about the same (it is located ____ to the primary
canine and in the mandibular it is located ____.)
◦ The maxillary primate space is between the lateral incisor and the canine, and in the mandibular arch, it is between the primary canine and the mandibular primary first molar.
• As she progresses, once we see full emergence of our 6’s, permanent ____, we see the spaces about the same in the maxillary arch, but it is closed in the ____ arch.
• We have ____ loss of primate space in the mandibular.
primate spaces mesial distally first molars mandibular early
- Quite a bit of crowding.
- IF we just say we will wait until she is 12 or older, the crowdind that she has will be much different.
- The tooth that is so protrusive will be more prone to traumatism over the course of time.
- It is not just simply esthetic, but more about consideration of ____ and instances of ____ to protrusive teeth.
growth effect
trauma
• So we started her treatment with use of a maxillary palatal expander
• We started with a lingual holding arch to preserve the ____ and use that space to
unravel the crowding that we have.
leeway space
- If look at what we accomplished, we used the leeway space to unravel the crowding and avoiding needing to have permanent teeth removed for her.
- We were able to expand the ____ to create space for the canine, and conserve leeway space in mandibular arch to address ____.
palate
anterior crowding
Timing of treatment?
• Timing of treatment is important because we see a patient at 6 and 7,
◦ but doesn’t mean they need treatment at that time.
◦ But sometimes we can miss an opportunity if we see a patient too late.
‣ If we see someone at 12, 14, older, and have ____, those are better treated earlier when growth potential is at our advantage and we can create ____ at accommodate teeth, and again, timing is essential to what we do.
‣ It doesn’t require urgency in other senses of immediate care, but it’s a sooner vs. later mentality when considering harnessing growth potential to our advantage.
posterior crossbites
space
