Fixed Appliances

Question 1

What kind of tooth movements are fixed appliances capable of?

Answer 1

Bodily movement, rotation, intrusion/extrusion, root control

Question 2

What force is needed for bodily movements on teeth?

Answer 2

50-120g

Question 3

What force is needed for torquing movements on teeth?

Answer 3

50-100g

Question 4

What force is needed for rotational movements on teeth?

Answer 4

35-60g

Question 5

What force is needed for extrusion movement on teeth?

Answer 5

35-60g

Question 6

What force is needed for tipping movement on teeth?

Answer 6

25-60g

Question 7

What force is needed for intrusion movements on teeth?

Answer 7

10-20g

Question 8

What are some advantages of fixed appliances?

Answer 8

All types of tooth movement is possible 
Allow bodily movement 
Groups of teeth can be moved
Detailed movement possible 
Essential for dealing with complex cases- ectopic canines, hypodontia, severe crowding

Question 9

What are the components of fixed appliances?

Answer 9

Brackets
Bands/bonded buccal tubes 
Archwires
Ligatures (eslastomeric or stainless steel)
Auxiliaries

Question 10

Where are bands usually placed?

Answer 10

Usually on molars or premolars

Stronger than bonded attachments- headgear, quad helix, occlusal forces, orthognathic surgery

Question 11

What are the features of bands?

Answer 11

Preformed stainless steel
Buccal attachment welded to band- lower 1 or 2 tubes, upper 2 or 3 tubes
Range of sizes
Lingual cleat sometimes

Question 12

How do you select a band size?

Answer 12

Separators for one week or less- warn patient re slight discomfort and advise re care/removal
Select correct band (U/L, L/R)
Try in and select a size which is a good fit
It should seat fully but be a neat fit

Question 13

How are bands placed?

Answer 13

Select band
Dry tooth
Cement using GIC (releases fluoride) and bite stick
Check position- parallel to cusps, fully seated but not over seated

Question 14

How do you place brackets?

Answer 14

Acid etching- 37%/40% phosphoric acid for 20-30 seconds
Wash and dry- enamel should look frosted, maintain dry field
Bonded with composite and light cured

Question 15

What is the arch wire sequence of fixed appliances?

Answer 15

Progress from flexible to stiff wire 
Progress from NiTi to SS wire 
Initial alignment 0.012”/0.014” NiTi 
Intermediate archwire 0.020” x 0.020” CuNiTi/0.017” x 0.025” CuNiTi
Working archwire 0.019” x 0.025” SS

Question 16

What are the advantages of the Begg appliance system?

Answer 16

It had 3 stages
It relies on extension
It has good speed of movement

Question 17

What are the disadvantages of the Begg appliance system?

Answer 17

Lack of precision

Question 18

What are the advantages of the Edgewise (Angle) appliance system?

Answer 18

Mechanically simple
Precise
Versatile

Question 19

What are the disadvantages of the Edgewise appliance system?

Answer 19

Slower speed of movement

Question 20

What are the current fixed appliance systems?

Answer 20

The Tip-Edge appliance- derived from the Begg appliance system
The Straight-wire appliance (SWA)- derived from Edgewise appliance

Question 21

What are some advantages of the tip-edge appliance?

Answer 21

Permits tooth tipping in early stages
Anchorage saving
Versatile
More precise than Begg

Question 22

What are some disadvantages of tip-edge appliance?

Answer 22

Narrow bracket with poor control
Requires intermaxillary elastics
Complex in stage 3
Based on extension philosophy

Question 23

What the stages of treatment with straight wire appliances?

Answer 23

Anchorage management 
Levelling and alignment 
Overbite correction/control 
Overjet correction 
Space closure 
Finishing and detailing
Initially- round flexible archwires 
Later in treatment- rectangular archwires

Question 24

What are some advantages of SWA?

Answer 24

Reduced wire bending- pre adjusted design 
Use of sliding mechanisms 
Precision and finishing 
Flexibility and biomechanics 
Multiple bracket design

Question 25

What are some disadvantages of SWA?

Answer 25

Friction Perceived anchorage demands Adjustments still required for individual patients Deceptive simplicity

Question 26

What is the difference between the original edgewise appliance and the SWA?

Answer 26

Original edgewise appliance required a lot of wire bending- 1st order bends (in/out), 2nd order bends (canine tip), 3rd order bend (incisor torque) SWA incorporates much of the wire bending into the bracket design

Question 27

What are the features of SWA brackets?

Answer 27

Stainless steel brackets Sometimes ceramic Rectangular horizontal slot 0.018” or 0.022” slot size

Question 28

As as GDP what can you do if a patient comes in with a missing bracket?

Answer 28

Enquire with the patient about what happened Risk inhaled- consult A&E for possible chest x-ray Risk ingested- seek advice from A&E

Question 29

As a GDP what can you do if the patient complains of acute gingival inflammation close to the attachment or band?

Answer 29

``` Intensive OHI Disclosing tablets Chlorhexidine gel/mouth rinse Localised scale and polish Contact orthodontist ```

Question 30

As a GDP what do you do if a patient comes complaining that their teeth feel loose from their braces?

Answer 30

Reassure Check for traumatic occlusion Check vitality/colour/TTP/perio issue Attend orthodontist

Question 31

As a GDP what do you do if your patient attends complaining that their teeth feel painful from their braces?

Answer 31

``` Reassure Analgesia Check there’s no damage to the appliance Check for traumatic occlusion Contact orthodontist ```

Question 32

As a GDP what do you do if your patient attends with a broken URA?

Answer 32

If broken clasp remove If broken acrylic, smooth rough edge Get patient to attend orthodontist

Question 33

As a GDP is a patient attends with a loose URA what do you do?

Answer 33

Adjust claps with spring formers Advise patient not to clock appliance in/out of mouth Advise to return to orthodontist

Question 34

As a GDP if a patient attends with a inflamed palate caused by their URA what do you do?

Answer 34

Query Candida infection OHI and diet advice Prescribe miconazole oromucosal gel