orthodontic appliances

Question 1

what are removable appliances?

Answer 1

-appliances that are not attached to the teeth-they can be removed for cleaning/sports

Question 2

what are the components of removable appliances?

Answer 2

BARA
-baseplate
-active component
-retentive component
-anchorage

Question 3

what active components are in removable appliances?

Answer 3

SSB
-springs
-screws
-bows

Question 4

what is the force applied by springs dependent on?

Answer 4

-length of wire
-radius of wire
-elastic stiffness of wire

Question 5

give examples of retentive components…

Answer 5

CLASPS
-Adam clasps
-delta clasps
-ball-ended clasps
-southend clasps

Question 6

what is the base plate made of?

Answer 6

acrylic

Question 7

what is the function of the base plate?

Answer 7

-holds all components together
-provides anchorage of the appliance

Question 8

define anchorage

Answer 8

anchorage is the resistance to unwanted tooth movements

newtons 3rd law

Question 9

how do you increase the anchorage?

Answer 9

-use more clasps
-move only 1 or 2 teeth at a time
-use lighter forces

Question 10

what are the advantages of removable appliances to patients?

Answer 10

-can be removed for cleaning and sports/hobbies

Question 11

what are the advantages of removable appliances to orthodontists?

Answer 11

-cheap
-less chair side time than fixed
-good anchorage
-can move blocks of teeth
-easy to adjust

Question 12

what are the disadvantages to patients?

Answer 12

-must be worn
-lower appliances less tolerated
-can temporarily affect speech/eating

Question 13

what are the disadvantages to orthodontists?

Answer 13

-dependent on pt cooperation
-limited movement
-retention post correction can be difficult

Question 14

what are the post op instructions for fitting removable appliances?

Answer 14

give verbal and written instructions:
-must be worn 24hrs/day
-can be removed for cleaning/sports/hobbies and eating if necessary
-warn of initial discomfort
-warn of initial difficulty eating/speaking
-inform pt/parent how to activate screw
-inform pt/parent who to contact if any problems

Question 15

when do you review fitting of removable appliance?

Answer 15

-4 weeks

then every 4-6 weeks

Question 16

what do you do at reviews?

Answer 16

-check OH
-check if any problems e.g sharp edges
-reactive active components
-teeth move approx 1mm/month
-note any speech problems
-check signs of wear
-encourage pt

Question 17

what are common problems seen at review of removable appliances?

Answer 17

-wear
-breakages
-appliance is loose
-poor pt compliance
-excessive tilting (spring in wrong position)
-candida infections
- poor OH- canidida and gingival inflammation

Question 18

what kind of patients do functional appliances require?

Answer 18

-good OH
-good compliance
-pre-adolescent growth phase

Question 19

what are the contra-indications of functional appliances?

Answer 19

-poor OH
-poor motivation
-non-growing pt (>15/16)

Question 20

give an example of a fixed functional appliance

Answer 20

Herbst appliance

Question 21

name a removable functional appliance

Answer 21

twin block appliance

Question 22

what are advantages of twin blocks?

Answer 22

-removable for cleaning
-may avoid extractions
-may accelerate growth
-may reduce incidence of trauma
-may reduce complexity of tx needs
-effective for class II malocclusions

Question 23

what are the disadvantages of twin blocks?

Answer 23

-affect speech and eating
-bulky appliance
-may cause ST trauma

Question 24

what are fixed appliances?

Answer 24

-made of brackets and wires
-attached to the tooth- cannot be removed by pt
-appliance moves teeth by wire and its interactions with bonds/brackets

Question 25

what are orthodontic wires made of?

Answer 25

-nickel titanium
-stainless steel

Question 26

what shapes do orthodontic wires come in?

Answer 26

-round
-rectangular

Question 27

name some fixed appliance types

Answer 27

-labial/lingual fixed appliances
-TPA
-QUAD HELIX
-RME
-TADS

Question 28

what kind of pt is suitable for fixed appliances?

Answer 28

-good OH
-free from pathology/disease
-motivated pt
-IOTN-suitability

Question 29

what are the contraindications of fixed appliances?

Answer 29

-poor OH
-poor motivation/attendance
-pathology/disease
-pre-existing root resorption

Question 30

what are the advantages for fixed appliances?

Answer 30

-full range of tooth movements are possible
-provides optimal tooth control
-flexible

Question 31

what are the risk of fixed appliances?

Answer 31

-poor OH
-caries
-gingivitis
-periodontitis
-ST trauma
-pulpal necrosis
-root resorption
-gingival recession

Question 32

what will be seen at end of fixed appliance tx?

Answer 32

-class I/II molars
-class I canines
-no spacing
-no rotations
-flat occlusal plane
-normal incisor angulting
-normal incisor inclination

Question 33

what is essential after fixed appliances?

Answer 33

retainers

Question 34

describe the importance of retainers?

Answer 34

-active phase
-retention phase

the biggest risk to orthodontics is relapse

Question 35

what is the current advice for retainers?

Answer 35

-must be worn 7 nights/week
-removable retainers are used for life
-removable must be worn even with fixed retainer

Question 36

what are the two main retainers used?

Answer 36

-hawley retainers
-clear plastic retainers

Question 37

what do fixed retainers need?

Answer 37

-maintainance
-removable retainer

Question 38

do clear plastic retainers require follow up?

Answer 38

yes in primary care- won’t last a lifetime and can be remade by gdp

Question 39

what orthodontic emergencies can be treated by therapists?

Answer 39

-broken removable retainer-can be remade
- all other removable appliances need referred

-wire out- can be cut in emergencies then referred
-all other problems with fixed appliances should be referred.

Question 40

what should you do if patients bracket has debonded?

Answer 40

-cover with wax to secure and refer

Question 41

if pt’s wire comes out of tube, what should do?

Answer 41

-rewire if skilled and cut wire distal to easy bracket excess
-if cutting wire-refer to orthodontists
-use wax to cover wire