Ortho revision notes Flashcards
Purpose of study models
pt motivators
to assess the pt’s occlusion
to design a URA
secondary opinion
tx planning
Advantages of ura
tipping teeth
excellent anchorage
pt can maintain oh
shorter chariside time than fixed
does not special training to fit applaince
can achieve block movements
non destructive of tooth tissue
Disadvantages of ura
specility training to design appliance and make
can only move one or two teeth
pt can easily reomove from mouth
cannot really achieve rotation movements
Active compoentn
the compontent which moves the tooth
Retention
the resitance to displacement forces
gravity
mastication
speech
tongue
active component
Anchorage
the resistance to unwanted tooth movement
Base plate
slef cured pmma - connector, retention, anchorage
S.S
itron -72
chromium -18
nickel - 8
titanium -1.7
carbon 0.3
durable, cariogenic, ductile, corrsion resistant due to presence of chromium, good asthetics, strong
Fitting a ura
ensure the pt details matches the details of the ura
ensure the design mataches the ura
run finger over the fitting surface to check for sharp edges
check the wirewokr intergrity
insert the appliance in the mouth and check for areas of blanching
check posterior retention - flyover then arrowheads
check anterior retention
acitve appliance
demo to pt
review 4-6weeks
Pt intructions for appliance
the appliance may feel big and bulky
may impinge on pt
initial pain and discomfort
exxcessive salivation my be presentable
remove for contact sports
wear appliance 24/7 including mealtimes
only remove appliance to clean after every meal
provide contact details
talk about complaince and appts
avoid hard and sticky foods
Benefits of ortho
improves speech, function and aesthetics
improves dental health
reduces trauam risk
Risks of ortho
relapse
root resorption
loss of vitiality
perio support issues
headgear trauma
decalcification
allergy
soft tissue trauma
ulcerations
toothwear
Root resoprtion
due to excessive movements, migh force, torque root movement, intrusion, prolonged
relpase high in
diastemmas, instanding 2’s lower incisors crowding, roations
Fixed retainer advatanges
fixed to teeth so good for compliance
done chair side
non invaasive
cheap
aesthetics
Fixed retainer disadvangates
OH maintaince hard
etch damages teeth
can easily debond
doen’t incoprate all teeth
Thermoplasitc retainer advatantages
cheap
aesthetics
non invasvie
oh better as can be removed by pt
incorpartes all teeth
thermoplastic retainer disadvantages
can easily be removed by pt so no complaince
distorts when applied to heat
easily lost
non resilant
Hawley retainer - advatnages
allows occulsal setting
strong
removable so oh good
minor tooth movement
incorpartes all teeth
disadvatanges of hawley retainer
aesthetics
intrudes on tongue space
expensive and time consuming to make
pt can remove
speech issues
Types of rothomovement
rotation
bodily movement
intrusion
extrusion
torque
tension
Components of fixed applaince
brackets
modulaes
archwire
force generating component - elasitic power chain, niti coils
anchorage - simple, compound, reciprocial, absolute (TAD), cortical - quadhelix, nance, transpaltal arch
Advantages of fixed
precise tooth movement
bodily movement forces of root
non invasive
can fix rotations
not bulky
pt cannot remove applince
Disadvatanges of fixed
etch can damage teeth
soft tissue trauam
relapse
root resoprtion
special training to fit
poorer anchroage
poor oh
expensive
Extra oral anchorage
headgear with intral oral bow attached to appliance
200-250g
Transpalatal arch
0.9mm hssw - rotation and anchirage
Palatal arch with nance button
anchorage but can cause erythamtous candidisosi due to being unable to clean underneath appliance
quadhelix
fan shape expansion
bilateral and asymmetrical expanision
habit breaker device
expansion in cleft paalte
rotation of molars
andrews 6 keys
class 1 incisors
class 1 molars
flat occlusal plane or slight curve of spee
long axis of tooth have slight mesial inclination
canine backs to molars have slight lingual inclination
tight approximal contacts between teeth
Expanding upper arch
please provide a ura to expand the upper arch
A - midpline paaltal screw
R - adamas clasps on 16,26,14,24
A - reciprocal anchroage
B - self cured PMMA + PBP
URA to redue oj and ob
please provide a ura to reduce oj and ob
A - roberts retractor 0.5mm with 0.5mm i.d tubing
R - adams clasps on 16, 26, mesial stops placed on 13,23, flattended 0.7mm hhsw
A - good as smal root teeth
B - self cured PMMA FABP - OJ +3mm
URA to retract 13,23
please provide a ura to retract the 13,23
A - 13,23 paaltal finger spring and guard - 0.5mm
R - 16,26, adams clasps 0.7mm hssw
A - goood as only moving 2 teeth
B - self cured PMMA
URA to crrect anterior crossbite
please provide a ura to correct anterior crossibite
A - z spring 0.5mm hssw
R - 16,26,14,24, adams clasps 0.7mm hssw
A - as on ly moving one tooth
P - self cured PMMA - PBP
URA to retract 13,23 and reduce ob
A - 13,23, paltal finger spring and guard
R - 16,26, amadams clasps 0.7mm hssw
A - only moving 2 teeth
B - self cured pmma - FABP - oj = 3mm
Why use flat anterior bite plane when correcting overbite
it allows the vertical dimension to be increased to allow overeuption of the posterior teeth
you add 3mm to oj to prvent the lowers from hitting the bite plane and causing truaama and relapse
Tubing and sheathing for some components
to improve stability and rigidity
URA to retract buccal placed 13 and 23 and redue ob
A - 13,23, buccal canine retratractors - 0.5mm hssw and 0.5mm id tubing
R - 16,26, adams clasps 0.7mm hssw
A - good as only moving 2 teeth
B - self cured pmma - FABP - OJ +3mm
Class 2 div 1
when the lower incosirs lie postieroir to the cingulum plateau of the upper incisors
theres is an increased oj
Problems
dental - OJ cause trauma issues
aesthetics - lip trap/ incomptent lips
ging drying causing gingivitis
Skeletal class 2
retrogntathic mandible - manidble further back than maxila
Could have sucking habits
Tx options for class2 div 1
accept and monitor
gorwth mod/ura to tip incosrs/ camoflaguage and severe cases surgery
Class2 div 2
when the lower incoors lie posteiror to the cingulum plataue of the upper incosirs
there upper incisors are retroclined
Issues - aethetics, deep overbite which can be trauamatic
higher lower lip line
crowding of 2’s caused by incosrs being retorclined
ectopical canines sometimes
Prognosis of class 2 div 2
diffcult to treat due to facial growth and rotated laterals likley to relaspe
retention required
tx for class2 div 2
accept and moniotr
functional applaince by converting to class 2 div 1
camofluage
align the upper only - difficult and chance of relapse
orthognathic surgery when growth is complete and severe discrepnancy, poor facal appearance
Class 3 issues
traumatic overbite
tmj issues
aestehtics
function and speech
ging recession
Class 2 div 1 issues
aesthetics
lip trap or incomptenent lips
retrgnthanic manidble
oj - which casues trauma
drying of ging leads to gingivities
habits - digit sucking
Class 2 div 2 issues
aesthetics
deep overbite
traumatic occlusion
ectopical cancines
crowing of 2’s due to retrcline of incisors
<LAFH
high lower lip line
Class 3
traumatic occlusion
ging recession
tmj issues
aesthetics
speech and function
AOB
posterioer crossbite biltateral