Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Module 8 > ORTHO URAs > Flashcards

ORTHO URAs Flashcards

(58 cards)

Start Studying
1
Q

what is a removable appliance?

A
  • fabricated mainly in acrylic and wire
  • not permanently attached to teeth
  • can be removed and reinserted by pt
  • often used an adjunct to fixed appliance tx
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are the active and passive components of removable appliances?

A

active: springs, biteplanes, screws, bows
passive: retainers e.g., hawley

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are the types of removable appliances?

A
  • interceptive appliance
  • space maintainer
  • pre surgical orthopaedics (cleft care)
  • active plate
  • retainer
  • functional appliance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

advantages of removable appliance?

A
  • removeable for OH and sports
  • increased anchorage
  • easy to adjust
  • less iatrogenic damage
  • baseplate can be modified
  • good at moving blocks of teeth
  • can be passive
  • lower cost
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

disadvantages of removable appliance?

A
  • need good pt compliance
  • limited movements - tipping
  • affects speech
  • technician required
  • lower appliances difficult to tolerate
  • inefficient at multiple tooth movements
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are the components of removable appliances?

A
  • active components
  • retentive components
  • anchorage
  • baseplates
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are springs constructed with?

A

0.5 or 0.7mm ss wire
18/8 austenitic ss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

why are there loops incorporated in springs?

A

the more wire, the greater the range of spring and the lighter the force exerted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what type of component is a spring?

A

active

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

how is the force of stainless steel springs calculated?

A

F = d.r (4)/ l(3)

r = radius of wire
d = deflection of wire
l - length of spring

*increasing radius of wire by 2 will result in the force increasing by 16 times
*increasing the length of the spring by 2 will reduce force applied by 8 times

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

how much force is required for a single tooth movement?

A

no more than 25-40 grams per tooth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

for a single tooth movement, where do you want to apply the force to?

A

close to the gingival margin of the tooth to reduce the tipping tendency to minimum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are examples of springs?

A
  • palatal finger springs
  • buccal canine retractors
  • Z springs
  • T springs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what type of component is a screw?

A

active

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

why would we add screws to a removable appliance?

A

embedded in baseplate to be activated by the pt turning a key - for expansion or distalisation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

how much separation does a quarter turn of the screw on a removable appliance create?

A

0.25mm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

disadvantages of removable appliance with screw?

A

bulky
more expensive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is clasped on a RA with a screw?

A

teeth being moved are clasped

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

how is retention of RA achieved?

A

clasps of various types of clasps/ cribs
- adams/ delta cribs: mainly used on molars and premolars
- southend and ā€˜Cā€™ clasps: for incisors
- ball hooks: interdental embrasures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what are adams cribs or delta clasps constructed with?

A

molar clasps in 0.7mm stainless steel round wire
premolar/ deciduous clasps in 0.6mm wire

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

why are adams/ delta cribs not ideal for primary teeth?

A

less of a bulbosity for retention

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what are southend clasps made with?

A

0.6/0.7mm stainless steel wire

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what are ball hooks made from?

A

0.7mm stainless steel wire with soldered ball on end

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

where do adams clasps/cribs engage?

Study These Flashcards
A

undercuts at the mesial and distal corners of the edges
should engage 1mm of undercut

25
what do you use to adjust adams clasps/ cribs?
adams pliers - arrowheads either: 1. move horizontally in towards tooth 2. move in towards tooth and also vertically towards gingival crevice
26
what are the names of the parts of an adams clasp?
arrowhead bridge
27
how can we reinforce anchorage with URAs?
1. clasp more teeth 2. move only 1 or 2 teeth at a time 3. use lighter forces 4. occlusal capping 5. add headgear
28
what is a baseplate?
connects components of the appliance - made from acrylic
29
what is the role of a baseplate in an URA?
- support anchorage through palatal coverage - active or passive baseplate - buccal capping - anterior bite plane (FABP)
30
why may you add an FABP to a URA?
if the patient has a deep bite - incisors will bite only acrylic which will hold the molars apart to allow them to over erupt to open the bite and allow movement of the incisors back
31
why may you add buccal capping to a URA?
if anterior teeth are stuck behind in a crossbite - you can open things up at the front to move the teeth over the bite
32
what is important regarding communication with the lab for a URA?
- good impression taken - tell them what the appliance is for - retention components specified - active components specified - baseplate modifications specified - pt details on both copies - draw the design on the lab slip - inform them for when it is required
33
what are you checking when you fit a URA?
- its the correct one for your pt!!! - no sharp edges on acrylic (esp in palatal rugae area) - fit in pt mouth and note any rocking, or areas that do not fit and adjust - tighten clasps and check retention - activate springs and check that teeth are free to move - chat to the pt, and ask about any discomfort - check the pt is able to insert and remove - give written and verbal instruction to pt and parent
34
what is the general instruction for care of URA?
wear 24 hours/ day warn of initial discomfort warn if initial lisping and drooling
35
what is checked at the review appt?
- chat to pt and note speech - check appliance out of the mouth for surface lustre, tooth imps on bite planes etc - check condition of mouth and note any trauma - check position of teeth that are being moved and the anchor teeth from the original study models
36
at the review appt, how should the palatal mucosa present if good URA wear?
indentation or redness
37
what suggests that the pt is not wearing their URA?
struggling with speech at review appt shiny surfaces on acrylic
38
what is completed at review appt?
teeth should be slightly mobile - reactivate springs 1-2mm and tighten cribs (show pt how to turn key) - congratulate pt if appropriate and reappoint -
39
how much tooth movement should occur each month with a URA?
approx. 1mm
40
what is an aligner?
clear, removable plastic appliance which can produce small tooth movements
41
what does treatment with aligners involve?
- a series of aligners - tooth movement is achieved by deformation of the aligner - composite attachments are often bonded to teeth
42
how many hours in a day should aligners be worn for?
22hours
43
what are potential additional features to aligner tx?
elastics attachments interproximal reduction
44
who can provide aligner tx?
specialists and dentists who have sought appropriate training and are competent to provide the treatment to a satisfactory standard
45
treatment for upper incisor (11) inside crossbite?
retention: adams cribs on 6/6 and 4/4 active component: Z-spring to1/ bite opening: posterior bite capping to 654/456 baseplate: to connect everything together and for some anchorage
46
treatment for all four incisors inside crossbite, with deep reverse overbite?
retention: adams cribs 6/6 and 4/4 anterior retention: southend clasp 1/1 active component: expansion screw to section 21/12 bite opening: occlusal capping posteriorly screw is opened by 1/4 turn 2xweek to push upper incisors over the bite
47
treatment for increased overjet, proclined incisors?
1. canine retraction - extract: 4/4 to allow overjet reduction - retention: Adams cribs 6/6, southend clasp 1/1 - active components: palatal finger springs 3/3 with wire guards for stability - bite opening: flat anterior bite plane 2. incisor retraction - retention: Adams cribs 6/6 with arrowhead extensions to 5/5 - metal stops mesial to 3/3 to prevent these from moving forward - active component: labial bow with large U loops - bite opening: flat anterior plane bite - labial bow activated 1-2mm at each visit by squeezing U loops together (palatal acrylic must be trimmed)
48
what are buccal canine retractors for?
moving buccally places canines
49
where should a helix be placed?
must be placed half way between the starting position of the tooth and the desired finishing position
50
if helix places far to anteriorly what happens?
tooth will move palatally
51
what happens if helix is placed far too distally?
tooth will move buccally
52
why is it necessary to reduce the overbite before reducing the overjet?
as incisors tip, the lower incisors prevent further overjet reduction due to increasing overbite
53
how can the overjet be reduced without increasing the overbite as the incisors tip palatally?
by incorporating an anterior bite plane
54
where would you trim to allow an incisor to retrocline?
trim palatal aspect with bur parallel to palatal surface DONT trim from occlusal surface as this reduces width of bite plane excessively
55
treatment for /5 deflected palatally and /6 drifted mesially?
retention: adams clasps on 6/46 and southend clasp 1/1 active component: screw section to /6 and Z spring to /5 (this pushes the 6 back and brings the 5 in line)
56
treatment for a buccally placed canine?
retention: adams cribs 6/6 and 4/4 anchorage reinforcement: headgear tubes 6/6 active component: screw section to distalise /456 medium pull on headgear
57
treatment for class II div I and both upper first molars are carious?
- adams cribs on 73/37 - finger springs 5/5 and 4/4 - fitted labial bow 21/12 - extract 6/6 - retract 5/5 - retract 4/4 - adams cribs 74/47 - finger springs 3/3 - southend clasp 1/1 - canines retracted - labial bow to retract 21/12
58
what are common problems treated with URAS?
- incisor crossbites - large overjet, proclined incisors - bucally placed canines

Module 8 (34 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions