2. RELAPSE
Definition : It has been defined as the loss of
any correction achieved by orthodontic
treatment.
3. Causesof Relapse:
1. Periodontal ligament traction:
Teeth moved orthodontically
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streching of periodontal principal fibres and the
gingival fibres encircling the teeth
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Fibres contract
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RELAPSE
4. 2.Due to growth related changes
Patient with skeletal problems associated
with class ii and class iii
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continued abnormal growth pattern after
orthodontic therapy
l .,.
RELAPSE
5. 3. BONE ADAPTATION
Teeth moved recently are surrounded by
lightly calcified osteoid bone.
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No adequate stabilization of teeth.
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RELAPSE
8. 7.Roleof third molars:
If third molar erupt after the orthodontic
treatment.
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Exert pressure on the teeth.
Late anterior crowding
RELAPSE
9. RETENTION
Defined as maintaining newly moved teeth in
position, long enough to aid in stabilizing their
correction. (Moyer)
Need Of Retention
1. Gingival and periodontal tissue refquire time post
treatment to reorganize
2. Soft tissue pressures are likely to cause relapse if
teeth are placed in an unstable position
3. Growth post-treatment maycause relapse
10. Principles of Retention
i, Relapse potential may be predicted by evaluation
of initial occlusion; teeth usually want to return to
their original position; this is due to gingival fibers
and unbalanced lip-tongue forces
:ii: Full-time retention is required for 3-4
allow for reorganization of PDL
onths to
:ii: Retention should continue for at least 12 months
in non-growing patients or until growth has ceased
in growing patients
11. SCHOOLS OF RETENTION
1 The Occlusal School
2. The Apical Base School
3. The Mandibular Incisor School
4. The Musculature School
12. THE OCCLUSAL SCHOOL
•According to KINGSLEY proper occlusion is a
key factor in determining the STABILITY of the
newly moved teeth.
13. THE APICAL BASE SCHOOL
ALEX LUNDSTROM (1920s) suggested that
the apical base is an important factor in the
correction of malocclusion and maintenance of
the stability of treated cases.
3t McCauley added that the inter c ine and
inter-molar widths should be
during or:!_hodontic therapy
. n i.li1ed
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14. THEMANDIBUlAR INOSOR
SCHOOL
Grieves and Tweed suggested that post
treatment stability was increased when
mandibular incisors were placed upright or
slightly retroclined over the basal bone.
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15. THEMUSCULA
TURE SCHOOL
x According to Rojers functional
muscle balance is necessary in
order to ensure post treatment
stabiIity.
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16. THEOREMS OF RETENTION
Theorem 1.
"Teeth that have been moved tend to return to
their former position"
Theorem 2.
"Elimination of the cause of malocclu ion will
prevent relapse"
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Theorem 3. J
"Malocclusion should be over corrected as a
safety factor"
-
17. Theorem 4.
"Proper occlusion is a potent factor in holding
teeth in their corrected positions"
Theorem 5.
"Bone adjacent the tissue must be allowed time
to reorganize around newly positioned teeth"
Theorem 6. , .
"If the lower incisors are based·up '•: ..., ver basal
bone they are more likely to remain in good
alignment"
18. Theorem 7.
"Corrections carried out during periods of growth
are less likely to relapse"
Theorem 8.
"The farther the teeth have been moved , the
lesser is the risk of relapse"
Theorem 9.
"Arch form, particularly in the mandi r arch,
cannot be permanently altered b .. g Jr nce
therapy" ·..
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Theorem 10.
V .....
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"Many treated malocclusions require permanent
retaining devices"
19. TYPES OF RETENTION
Retention can be three types :
1. Natural or no retention
2. Limited or short term retention
3. Prolonged or permanent retention
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20. NA
TURALO,RNO RETENTION
Conditions that do not require retention are:
Anterior crossbite.
Serial extraction procedures.
Posterior cross bite in patients having steep
cusps.
Highly placed canines in class 1 ex ra.tion cases.
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21. LIMITED OR SHORT TERM
RETENTION
Most cases routinely treated fall in this category.
Retention is given to allow bone n POL tissues to
adapt in their new location.
1. Class I, class II div 1 and div 2 cases, treated by
extractions.
2. Deep bites.
• •
3. Class 1-oon extraction with dertitam·es showing
proclinatiori"and spacing. J
22. PROLONGED ORPERMANENT
RETENTION
Cases requiring permanent retention are
1. Midline diastema.
2. Severe rotations.
3. Arch expansion achieved without ensuring good
occlusion.
4. Certain class 11,div 2 deep bite c, es
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.s. Patients witt_labnormal musculatu .. or tongue
habits.
e. Expanded arches in cleft palate patients.
23. RETAINERS
3t Retainers are passive orthodontic appliances
that help in maintaining and stabilizing the
position of teeth long enough to permit
reorganization of supporting structures after the
active phase of orthodontic therapy
Three types:-
1. Removable Retainers
. Fixed Retainers
3. Active Retainers
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24. Criteria for a Good Retainer
x Should retain all teeth that have been
moved into desired positions.
x Should permit normal functional forces to
act on the dentition.
Should be self cleansing and sh permit
oral hygiene maintenance. ..,.'...
:.
-x
- Should be as inconspicuous as possible. _
25. REMOVABLE RETAINERES
1. Hawley's
aootiance
2. - Designed in 1920
by Charles Hawley.
Most frequently used
retainer
Consists of claps on
molars and a short
labial bow extending
from canine to
canine having
adjustment loops
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29. BEGG'SRETAINER
<I '• " L
at Consists of a labial wire that extends till the
last erupted molar and curves around it to
get embedded in acrylic that spans the
palate.
Advantage:
There is no cross over wire thatre'.)(te ds
between._!he canine and premo r therebY._
eliminatingthe risk of space opening.
30.
31. CUP-ON RETAINER ORSPRING
REALIGNER
Appliance made of wire framework that runs
labially over the incisors and then passes between
canine and premolar and is recurved to lie over
lingual surface.
Both the labial as well as lingual segments are
embedded in a strip of clear acrylic.
Used to bring about correction o f - t a ions
Less-comfo
...
r
...t
. able than Hawley
Not as good in overbite maintenance
........
Indicated in perio cases where splinting is needed
32.
33. WRAPAROUND RETAINER
11 Extended version of springaligner . - - - - - - - - - - - -
•
that covers all the teeth.
Consists of wire that passes along
the labial as well as lingual
surfaces of all erupted teeth which
is embedded in a strip of acrylic.
"' ·1izing a periodontal!
weak dentition,-... , , .
Not routinely used.
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34. KESLING TOOTH POSITIONER
Described by H.D Kesling in 1945
Made of thermoplastic rubber like material that spans the inter
- occlusal space and covers the clinical crowns of the U/L
portion of teeth and a small portion of the gingiva.
" Needs no activation at regular intervals and is durable
" Disadvantages
l.
2.
3.
. '
Bulky an'd i ,,
time. J
(0 wear full-
Difficulty in speech and risk of
TMJ problems
Do not retain incisor position as
well as a conventional retainer
b/c patients usually wont wear
-
35.
36. VACCUM-FORMED (ESSIX)
RETAINER
• Developed in 1993
" o
r .
• This is a oo!yorogy!ene or go!yyjny!chl• • •
030" thick.
• Plastic removable appliance
• Advantages:
• Esthetic
• Patient is more likely to wear
• Inexpensive
• Quickfabrication
.- Minimal bulk
-
• High strength
• No adjustments
• Usually does not interfere with speech or function
• Studies have determined that Essix retainers are as efficient as Hawley-type
or bonded wire retainers
37. DAMON SPLINT
* Basically, upper and lower Essix
retainers connected
* Retentive splint for Class II, Class Ill,
and bilateral crossbite treatment
* Assists in tongue training
* Holds teeth and arches in corrected
position
'tition
L
•Designed By Dr. Dwight Damon
•Can be used by adults or patients in mix . '
•Minimal vertical opening to allow for air" •
·Esthetic. ' J
•Can be made using hardpressureformed, dual hardness/soft
liner and elastic silicone.
38. * Advantages of removable retainer
, Reestablishes normal tissue when gingival hyperplasia is
present.
,. Maintains occlusal relationship and intra-arch position.
a Unlikely to break.
•- Can be made with jaws rotated down and back to prevent Class
Ill relapse.
s Can be constructed to prevent relapse i < e l alClass II and
I
0pen bite cases •
••
'•
Growth control is less effective'than part-time funcuonal
appliance or headgear
39. FIXED RETAINERS
A! Utilized in cases where stability is questionable and
prolonged retention is planned
Four main indications:
1. Maintaining lower incisor position
2. Diastema maintenance.
----
3. Implant or pontic space mairitenCJlll.,i;;;,
4 Retaining closed extraction spaces
• •
40. 1. Maintaininglowerincisor position
during late mandibular growth:
• Even mild mandibular growth between
the ages of 16-20 can cause lower
incisor relapse
• A fixed lingual bar bonded only to
canines can prevent distal tipping of
lower incisors
• A heavy wire, 28 or 30 mil, should be
used due to long span ..
..'.
....,'
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• Studies indicate that placing retention
loops on canines willdecrease
breakage
41. * If teeth were severely rotated or spaced, all teeth (3-3) can
be bonded together using a 17.5 mil braided steel wire -
as it is not desirable to use too rigid of a wire (must allow
physiologic tooth movement)
* Patients who were evaluated after 2 o m r s o.flhaving a
lower fixed retainer showed NO sigh·ssfql;"' oaontal
problems --. J
-
* If proper flossing is maintained, fixed retainers can remain
indefinately
42. 2. Holdingdiastema closed:
* Utilize lighter wire
(17.5 or 19.5 mil twist)
* Bond above cingulum -
out of occlusion
* Can prevent bite deepening if
lower incisors erupt
43. 3. Implant or pontic space maintance:
* Reduces mobility of teeth making it easier to place
bridge
* Holds space if prolonged periodontal treatment is
required post-ortho, prior to placement of restoration
* Implants should be placed as soon a ho is
....@1.tages of
completed so it can be included jn
•
retention
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44. * For posterior teeth, heavy wire is bonded to shallow
preparations in adjacent teeth
* The longer the span, the heavier the wire
* Placed out of occlusion
* For anterior teeth, a pontic can be place
r-
etainer for short term use
.
- , . Ifthe patTent._must wait an extended.period of time priot.to
completion of ve·cal owthfor tacement of final restoration,
a bonded bridge I en
1
1
1a, etnovable
0
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45. 4. Retaining closed extractionsspaces:
* Placed on facial surfaces of posterior teeth
* Mainly used in adults, as they tolerate this better than
removable retainers
* More reliable than removable retainer
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46. FIXED RETAINERS TYPES
The Fixed Appliance
Banded Canine to Canine Retainer:
3
G Bonded Lingual Retainers:
Band and Spur Retainers
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47. BANDEDCANINE TOCANINE
RETAINER
Commonly used in lower anterior region
Canines are banded and a thick wire is contoured
over the lingual aspects and soldered to the canine
bands
The bands predispose to poor oral hygeine and are
unesthetic.
48. BOND1
EDUNGUAL RETAINER
Retainers bonded on the lingual aspect
x S.S wire is adapted lingually to follow the anterior
curvature.
x Ends are curved over the canines where its
bonded.
x Various pre fabricated lingual retai,,.,..,...s also are
available that can be bonded on e eth
I I t V
."
Recently use of spiral wire is recommended that
can be boneded to eachtooth individually.
49.
50. BANDANDSPUR RETAINER
x Used in cases where single
tooth has been orthodontically
treated for rotation correction
or labio lingual displacement.
51. Advantages of Fixed Retainer:
x Reduced need for patient corporation
x Can be used when conventional retainers
cannot provide same degree of stability.
x Bonded retainers are more esthetic
x No tissue irritation unlike what may been
seen in tissue bearing areas o wley's
retainer ....''
..,' ,.
x Can be--used for permanent and semi -
permanent retention.
x Do not effect speech.
52. Disadvantages of FixedRetainers
More cumbersome to insert
:Ii: Increased chair side time
More expensive
Banded variety may interfere with oral
hygiene maintainence
:it More prone to breakages
.......Loss of althy tooth mateJial
:it Tend to discolor
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53. RETENTION:CLASSII
Relapse in these patients are most likely due to a combination of
dental and skeletal changes
Dental changes (short-term relapse) :
* 1-2mm of A-P change tend to occur immediately following
treatment, especially when Class II elastics are used
Overcorrection is important in preventin re
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* Forward movement of lower incisors more than 2mm will
require permanent retention, as lrp pressure tends to upright
these teeth, leading to an increase in crowding, overbite, and
overjet
54. Skeletal changes (long-term relapse):
• Depends on age, sex, and maturity
• If original growth pattern continues, treatment that involved
growth modification will most likely result in loss of at least
some correction
• Continue headgear at night along with retainer
• Use a "passive" functional appliance (activator/bionator) to
hold position at night and conventional retainers during day
(continue for 12-24 months)
• Patients most likely to require these treat..,....,.
1) The_y@nger the patient at the end df t. D m e
2) The greatel'..the initial Class II problem
• Much easier to prevent re1apse than to correct later
...
55. RETENTION brought about by:
x Bionator/ Activator
* Maintain occlusal relationship
* Bite registration is taken in CR,
so appliance is "passive"
3_J· ot-edg to edge like when
used for ,, a
cive" Class II
correction -
56. RETENTION: CLASS III
Relapse occurs mainly from mandibular growth
Use of chin cups to restrict mandibular growth has been recommended
by some authorsto counter the continued growth tendency of mandible
But Chincups and functional appliances: rotate mandible downward
causing more vertical growth.
* Not as effective as maintaining Class II
If relapse occurs in normal or excessive face h e i g h tients: may need
surgical correction after growth
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.. ,.
In ress severe C'9ss Ill cases: Utilize functi.9l'lal app iances s u c s
reverse activator,t=R 3 or class Ill bionator or positioner.
* Will maintain occlusal relationship in these cases
* May position jaws down and back to prevent relapse
57. RETENTION: DEEP BITE
Must control overbite during retention
period
Construct upper removable retainer with a
baseplate to prevent lower incisors from
over-erupting; posterior occlusion is
maintained
After stability is achieved, worn at night
only
Nanda and Nan da found that the pubertc;1I
growth spurt in deep bite patients is 1.5-
•
2
years later than that of openbite cases;
therefore longer retention period is
required for deep bite cases
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58. RETENTION: ANTERIO,ROPEN
BITE
Patients with habit (thumb or tongue):
* Relapse occurs due to incisor intrusion.
* Important to control the habit.
Patients without habit:
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* Relapse is due to excessive growth tendencies and
continued eruption of posteriors mainly upper molars
(extrusion).
* Important to control eruption of upper molars.
59. Best retained by high pull headgears to
upper molars with use of conventional
removable retainers.
Appliance with posterior bite blocks (open
bite activator or bionator) at night and
conventional retainers during the day
Use of bite block appliances such as posterio
bite plane streches the musculature and
produces an intrusive force on the dentition
• Preferred because:
• Prevents eruption of upper an
lower molars
• Better patient acceptance--
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