Retention and Relapse

Question 1

retention

Answer 1

maintaining newly moved teeth in position long enough to aid in stabilizing their correction

Question 2

relapse

Answer 2

the term applies to loss of any correction achieved by orthodontic tx

Question 3

occlusal stabilization

Answer 3

involves hemeostasis: the masticatory system should be self-stabilizing after orthodontic tx

Question 4

destabilizing ffactors

Answer 4

1. persistant etiology
   - like thumb sucking
2. unstable occlusion
3. stretched fibers
4. muscle imbalance
   - strong chin / cheeks can pull things
5. third molars?
   - cause relapse? – non- significant in terms of anterior crowding
6. continued growth
   - sometimes finish treatment before done growing

Question 5

why ortho retention

Answer 5

b/c after treatment - tissues need time to rerganize – gain memory

pressure from soft tissue needs to be counteracted upon - due to inward pressure

changes produced by growth need to be maintained

Question 6

retention is most of the time has to be

Answer 6

passive

Question 7

phases of retention 1-3

Answer 7

1 – changes that occur in the first weeks - settling, closure of band space

2- possibly unfavorable - in reponse to residual tissue tensions & unbalanced functinal relationships (after 2-3 weeks)

3 - due to post treatemnt growth and persistant habits with lifetime effects

Question 8

mechanical retention can be __ or ___

Answer 8

removable or fixed

Question 9

hawley retainer

Answer 9

removable appliance for retention

• most common
• allows settling of occlusion (does not cover occlusal surfaces)
• 020-036 round stainless steel wires with acrylipc

adams clasp - wrap around molar and go into and through the occlusal embrasure - used in the conventinoal hawley

Question 10

good retainer use for bicuspid extractions

Answer 10

wrap around retainer

Question 11

wrap around retainer + use

Answer 11

use in extraction cases

• from distal to distal
• but allow more movement

does not go back onto the lingual side of the teeth *

Question 12

if occlusal coverage - implication

Answer 12

will not allow for quick settling (like hawley retainer)

Question 13

fixed retainers not good for

Answer 13

deep bites

b/c has to go apical to contact point (like on maxillary arch)

Question 14

matreials to use for lingual fixed retainer

Answer 14

coaxial twisted wire 0.0915”

plier

pin and ligature cutter

heavy wire cutter

phosphoric acid (etch)

bonding agent

FLOWABLE COMPOSTITE *** (NOT packable)

curing light

cotton rolls

Question 15

essix retainer

Answer 15

clear, esthetic, occlusal coverage (NO oclusal settling), temprary retainer, pontics can be added

Question 16

positioner is?

Answer 16

monoblock – puts teeth into final position

Question 17

fixed retainers are

Answer 17

bonded - but can still break not permanent

Question 18

why fixed?

Answer 18

less hands on than removable and sometimes more patient compliant

consider these if

• diestama was present
• teeth were rotated
• extraction socket was closed

Question 19

lingual fixed retainers she likes

Answer 19

braided thinner wire from canine to canine

Question 20

more hygenic lingual retainer

Answer 20

the loopy one - more easier to floss

Question 21

appliances cna also be retainers?

Answer 21

yes - passive forces suporting the space for future implant

Question 22

flowable or composite for fixed lingual retainers?

Answer 22

FLOWABLE – thixotropic propertied

Question 23

process of applying lingual retainer - fixed

Answer 23

use floss or the wires to go through the five interproximal spaces (canine to canine) and act as holders

present wire in place - pull wires or floss lightly to pull into place

etch - rinse and dry

bonding

flowable composite - covers and leaves completely smooth

remove ligatures

Question 24

supracrestal fibers remodel ___

Answer 24

SLOWLY

• example - in rotated teeth

Question 25

reason for some relapse

Answer 25

the supracrestal fibers are very stretched and remodel slwoly - so can take approx. 282 days after correction to be remodeled

Question 26

supracrestal fiberotomy

Answer 26

ADJUNCT to mechanical retention (not replacement)

• considered for severley rotated teeth
• involves severing the supracrestal fibers to reduce the relapse tendency following correctio of rotated teeth

detaching these fibers allows them to heal in a a “new” position – preventing the teeth from being pulled back to that original position

Question 27

frenectomy is used for

Answer 27

adjunct to mechanical retention - if low attachment remains - can pull teeth and gums still after treatment

Question 28

interproximal reduction can be used for

Answer 28

adjunct to mechanical retention

making sure contacts are stable!

Question 29

successful retention is achieved by what main 3 points

Answer 29

compliance

hygiene

identifying relapse (the potential causes early)

Question 30

successful retention protocol

Answer 30

LIFELONG
year 1 = 24-7
year 2 = night-time
year 5 and onwards = every other night

Question 31

relapse is

Answer 31

loss of any correction achieved by ortho tx

Question 32

common causes of relapse are

Answer 32

disharmonious growth

occlusal interferences

lack of retention correction

lack of tissue reorganization

muscular forces

Question 33

key points to keep in mind with retention and relapse

Answer 33

1. teeth that have been moved tend to return to their former position
2. elimination of the cause of malocclusion will prevent recurrence
   - example - use myofunctional therapy as well
3. malocclusion should be overcorrected as a safety factor (class 3 correction may go slightly to a class 2 to compensate for potential relapse)
4. proper occlusion is a potent factor in holding teeth in their corrected positions
5. bone and adjacet tissues must be allowed to reorganize around newly positioned teeth
6. corrections carried out during periods of growth are less likely to relapse
7. the further teeth have been moved - less liklhood of relapse (small space or tilting correction can easily go back)
8. arch form, particulary in the mandibular arch, cannot be permanently altered by appliance therapy

Question 34

many treated maloclusions require

Answer 34

permanent retaining devices

Question 35

what are self retaining?

Answer 35

single tooth anterior - cross bites

as soon as it ‘jumps the bite’ will stay on that side