Retention and Relapse Flashcards
retention
maintaining newly moved teeth in position long enough to aid in stabilizing their correction
relapse
the term applies to loss of any correction achieved by orthodontic tx
occlusal stabilization
involves hemeostasis: the masticatory system should be self-stabilizing after orthodontic tx
destabilizing ffactors
- persistant etiology
- like thumb sucking - unstable occlusion
- stretched fibers
- muscle imbalance
- strong chin / cheeks can pull things - third molars?
- cause relapse? – non- significant in terms of anterior crowding - continued growth
- sometimes finish treatment before done growing
why ortho retention
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
retention is most of the time has to be
passive
phases of retention 1-3
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
mechanical retention can be __ or ___
removable or fixed
hawley retainer
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
good retainer use for bicuspid extractions
wrap around retainer
wrap around retainer + use
use in extraction cases
- from distal to distal
- but allow more movement
does not go back onto the lingual side of the teeth *
if occlusal coverage - implication
will not allow for quick settling (like hawley retainer)
fixed retainers not good for
deep bites
b/c has to go apical to contact point (like on maxillary arch)
matreials to use for lingual fixed retainer
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
essix retainer
clear, esthetic, occlusal coverage (NO oclusal settling), temprary retainer, pontics can be added
positioner is?
monoblock – puts teeth into final position
fixed retainers are
bonded - but can still break not permanent
why fixed?
less hands on than removable and sometimes more patient compliant
consider these if
- diestama was present
- teeth were rotated
- extraction socket was closed
lingual fixed retainers she likes
braided thinner wire from canine to canine
more hygenic lingual retainer
the loopy one - more easier to floss
appliances cna also be retainers?
yes - passive forces suporting the space for future implant
flowable or composite for fixed lingual retainers?
FLOWABLE – thixotropic propertied
process of applying lingual retainer - fixed
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
supracrestal fibers remodel ___
SLOWLY
- example - in rotated teeth
reason for some relapse
the supracrestal fibers are very stretched and remodel slwoly - so can take approx. 282 days after correction to be remodeled
supracrestal fiberotomy
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
frenectomy is used for
adjunct to mechanical retention - if low attachment remains - can pull teeth and gums still after treatment
interproximal reduction can be used for
adjunct to mechanical retention
making sure contacts are stable!
successful retention is achieved by what main 3 points
compliance
hygiene
identifying relapse (the potential causes early)
successful retention protocol
LIFELONG
year 1 = 24-7
year 2 = night-time
year 5 and onwards = every other night
relapse is
loss of any correction achieved by ortho tx
common causes of relapse are
disharmonious growth
occlusal interferences
lack of retention correction
lack of tissue reorganization
muscular forces
key points to keep in mind with retention and relapse
- teeth that have been moved tend to return to their former position
- elimination of the cause of malocclusion will prevent recurrence
- example - use myofunctional therapy as well - malocclusion should be overcorrected as a safety factor (class 3 correction may go slightly to a class 2 to compensate for potential relapse)
- proper occlusion is a potent factor in holding teeth in their corrected positions
- bone and adjacet tissues must be allowed to reorganize around newly positioned teeth
- corrections carried out during periods of growth are less likely to relapse
- the further teeth have been moved - less liklhood of relapse (small space or tilting correction can easily go back)
- arch form, particulary in the mandibular arch, cannot be permanently altered by appliance therapy
many treated maloclusions require
permanent retaining devices
what are self retaining?
single tooth anterior - cross bites
as soon as it ‘jumps the bite’ will stay on that side
