Ortho Lab 2

Question 1

Fitting a URA

Answer 1

1. Ensure patient details match details supplied for the appliance
2. Check appliance design matches design specification
3. Run finger over fitting and polished surfaces looking for sharp or traumatic areas
4. Check integrity of the wiredwork
5. Insert the applicance and look for areas of blanching or soft tissue trauma
6. Check posterior retention - first flyovers, then arrowhead are correctly engaging undercuts
7. Apply principles to anterior retention
8. Activate appplicance - approx 1mm a month
9. Demonstrate to the patient the correct procedure for insertion and removal of appliance and get patient to demonstrate back
10. Reveiw 4-6 week appt

Question 2

Patient info and instructions

Answer 2

1. Applicance will feel bulky and big - reassure patient they will get used to it quickly
2. May cause initial excessive salivation - Explain it will pass within the first 24hrs
3. May impinge on speech for a short period - practice reading a book outloud
4. May cause initial discomfort or ache - reasure that this means the appliance is working
5. Wear 24/7 including mealtimes and sleeping
6. Remove applicance after each meal and clean with a soft bristle brush
7. Remove appliance when participating in contact or acitve sports as likely to take a sharp intake of breath
8. Avoid hard and sticky foods that may damage appliance
9. Mention about missing appts and non complaince and how this will lengthen treatment time
10. Provide emergency contact details

Question 3

Please construct a URA to retract 13 and 23 and reduce overbite

Answer 3

Active component - 13, 23 palatal finger spring and guard, 0.5mm HSSW
Retentive - posterior retention - 16, 26 Adams clasp 0.7mm HSSW
- anterior retention - 11,21 southend clasp 0.7mm HSSW
Anchorage - good as only moving 2 teeth
Baseplate - self cured PMMA acrylic - need to make baseplate modification
- Flat Anterior Biteplane (FABP) = OJ + 3mm (only used for correction of OB!!!)

Question 4

Why use a FABP?

Answer 4

it creates a bite plateform
Anterior teeth occlude against, lower teeth against and creates an overbite in posteior teeth and will continue to erupt - can get overeruption of lower teeth

Question 5

Why add extra 3mm to FABP?

Answer 5

It makes the bite platform bigger
Prevent the lower teeth biting behind the platform and the angle of the lower teeth tilted backwards and becomes more veritcal, increasing the OJ - teeth tilted in the wrong direction

remove bite platform when teeth are occluded

Question 6

Please construct a URA to retract buccally placed 13 and 23 and reduce OB

Answer 6

Active component - 13,23 buccal canine retractors 0.5mm HSSW and 0.5 I.D tubing (wire work to mesial aspect of the 2nd premolar so that the canine moves to that position)
Retentive - 16 and 26 adams clasp 0.7mm HSSW
- 11,21 southend clasp 0.7mm HSSW
Anchorage - good as only moving 2 teeth
Baseplate - self cured PMMA
- FABP - OJ + 3mm

Question 7

Please construct URA to correct anterior crossbite in 12

Answer 7

Active compoent - Z-spring 0.5mm HSSW on 12 (push forward by activating coils, rotate - adjust 1 coil more than the other, opposing coil causes rotation on opposite side)
Retentive - 16,26 Adams clasp 0.7mm HSSW
- 14,24 Adams clasp 0.7mm HSSW
Anchorage - good as only moving one tooth
Baseplate - sellf cure PMMA
- PROBLEM -lower teeth must be taken out of occlusion to bring forward
- Use posterior bite plane - incorprates all upper posterior teeth so lower can bite against - pushes 12 forward, soon as OJ remove applaiance and 12 will drop down

Question 8

Passive components?

Answer 8

Stops - 0.7mm flattened - holds it in position, passive bite of wire

Question 9

Advantages of adams clasp

Answer 9

Small and neat
Used on primary and permanent teeth
No specalised pilers
Any tooth 
Modified as needed