BDS3 session 2

Question 1

URA retract canines

Answer 1

take out 4s
A - palatal finger springs 0.5mm hssw
R - adams on 6s, southends on 1s
A - moving 2 teeth
B - self cure PMMA

Question 1

what is bone remodelling controlled by?

Answer 1

PDL

Question 2

URA design retract canines and reduce overbite

Answer 2

take out 4’s
A - palatal finger springs 0.5mm hssw
R - adams on 6s, southends on 1s
A - moving 2 teeth
B - self cure PMMA
FABP overjet +3mm

Question 3

uses of study casts

Answer 3

• tx planning when patient not there
• used to make dentures
• foresnics
• teaching
• patient encouragement
• medical and legal records
• diagnosis
• 3d model mouth
• retrospective studies

Question 4

defintion overbite

Answer 4

• vertical overlap incisors

Question 5

defintion overjet

Answer 5

upper front eeth protrude outward
- horizontal measurement

Question 6

diff between heat cured and light cured pmma

Answer 6

• heat cured less porous, hard and easier to clean last longer
• self cured quick and easy to use and don’t need ot send to lab

Question 7

what are displacement forces that can dislodge URA?

Answer 7

• mastication
• talking
• gravity
• tongue
• newton 3rd law

Question 8

what happens of too great force put on tooth?

Answer 8

• damage to PDL, cuts off blood supply resulting necrotic tooth
• bone won’t have time to remodel

Question 9

advanatges of URAs?

Answer 9

Tipping of teeth
Excellent Anchorage
Generally cheaper than fixed
Shorter chairside time required
Oral hygiene is easier to maintain
Non- destructive to tooth surface
Less specialised training required to manage
Can be easily adapted for overbite reduction
Can achieve block movements

Question 10

disadvantages of URAs?

Answer 10

-Less precise control of tooth movement
- Can be easily removed by the patient
- Generally only 1-2 teeth can be moved at one time
- Specialist technical staff required to construct the appliances
- Rotations very difficult to correct