2. Contents
Introduction
Fitting a new removable appliance
Subsequent visits
Activation
Headgear
Clinical management of functional appliances
Conclusion
3. Introduction
It is at the beginning of treatment that the foundations of the future success of
treatment are laid. Chairside management begins with assessment of the patient and
formulation of a treatment plan .
It is at this stage that patient commitment and motivation must be assessed. Failure to
appreciate possible problems and to discuss them with the patient can prejudice the
future cooperation.
A badly designed or constructed appliance will be difficult to wear and can undermine
the cooperation of even the most enthusiastic patient.
4. From the outset, the orthodontist must determine whether the prospective patient
is a suitable candidate for treatment
For the individual who is convinced he or she will require orthodontics, an
important question is whether any one feature is of great concern than the other.
The orthodontist should make some diagnostic determinations from the doorway
regarding the patient’s face, posture and expression.
One can often tell from the first moment whether the orthodontic problem will be
largely a dental one or a difficult skeletal or facial problem
5. Records
Good records are essential at the start of any treatment
An aid in the initial diagnosis and treatment planning
Serve as a reference point during treatment.
6. Study models
The impressions should be taken using trays with deep flanges or built up with wax to
ensure that the full depth of the buccal sulcus is reproduced.
The models should be cast with adequate bases, the upper being trimmed
symmetrically about the medial palatal raphe and the lower correspondingly.
The posterior surfaces of the models are trimmed flush so that the models can be
related in occlusion by laying them backs-down on a flat surface.
7. Radiographs
Confirm the position of any unerupted teeth
Condition of the alveolar bones.
Important before deciding upon the choice of teeth for extraction
Useful in the event of untoward damage to the teeth during
treatment.
The normal radiograph would be a dental pantomogram (dpt).
For removable appliance lateral skull radiographs are not
essential.
8. Photographs
Photographs form an important record of the patient's occlusion and
appearance
Intraoral photographs should include an anterior view and right and
left buccal views with the teeth in occlusion.
Extraoral views should show full face and profile.
9. Fitting a new removable appliance
The appliance should have been designed at the time of taking the impression and
with the patient still in the chair.
It can represent false economy to attempt to move too many teeth with one
appliance.
Show the appliance to the patient and demonstrate the retaining clasps and active
springs.
The appliance should be fitted within 1 or2 weeks after the impression has been
taken.
10.
11. Adjustment of clasps
Clasps made according to Adams' design offer good retention
When adjusting clasps the operator should avoid, as far as possible, bending the wire at
points where it has already been bent during construction by the technician .
The only exception to this rule is that where the clasps are initially too tight to permit
insertion, it may be necessary to grip each arrowhead in turn with the pliers and bend it
outwards .
Once the appliance can be seated (if necessary with the support of a finger) the accurate
positioning of the arrowheads can be investigated.
12. Possible faults are as follows:
Horizontal
The arrowheads do not contact the tooth or
else grip it too tightly.
Vertical
The arrowheads grip too far occlusally or else push up into the gingivae.
Bending the wire just beyond the point where it has passed over the embrasure
controls its vertical position.
Bending it nearer to the arrowhead controls its bucco-lingual position
13.
14.
15. It is important that the clasp does not grip the tooth too tightly and an undercut
of 0.25 mm has been shown to give an adequate clasp.
It Is useless to attempt to tighten the clasp by bending the wire at the point
where it emerges from the acrylic.
The only indication for adjustment at this point occurs in a case where the wire
passes high over the embrasure and interferes with the occlusion
16. Adjustments to the acrylic
The acrylic will need to be trimmed to permit active tooth movement. This is of
great importance but is frequently overlooked.
The appliance should be inspected in situ to ensure that no part of the acrylic
contacts the tooth to be moved and that this tooth movement will not result in
contact before the next visit
It is also sensible to trim the acrylic so that any desired passive movement might
occur
17. Bite planes
Any excessive thickness may need to be reduced and bite planes
adjusted to give even contacts.
Posterior bite planes, careful trimming will usually be necessary to
ensure that the occlusion is evenly distributed.
An anterior bite plane will need to be undermined on an appliance
designed to reduce an overjet before activating the labial spring.
18. Adjustment to active wirework
It is sensible to provide only very light activation so that the appliance is
self-activating and the springs cannot readily slip into the wrong position.
This will imply activation of about 1 mm for a palatal spring and 0.5 mm for
a 0.7 mm buccal spring.
During the first few days with a new appliance the patient has to get used
to inserting it correctly, must adapt to its presence and perhaps put up with
a mild degree of discomfort
19. Demonstration to the patient
Show the patient the appliance in the mouth using a mirror, demonstrating how it
should be inserted and removed.
Removal should be achieved by exerting finger pressure on the bridges of the
Adams' clasps on the first molars to disengage them before the front of the
appliance is disengaged.
Allow the patient to remove and replace the appliance in front of you.
Check that the appliance has been seated correctly, paying particular attention to
the position of active springs after the patient has inserted it.
20. As far as possible, cleaning should be carried out after meals and particular care
should be given to cleaning the fitting surface of the appliance either with a nail
brush or with the patient's own tooth brush.
Keep the appliance in a small, rigid box which will protect it from accidental damage.
Initially the patient will be very aware of the large bulk of the appliance and may
experience excess salivation and difficulty in swallowing.
Reassurance should be given that this is quite normal and that the appliance will
rapidly feel more comfortable.
Difficulties with excessive salivation and swallowing usually disapper within a few
hours. Normal speech may take 24to 48 hours to achieve.
21. Information
The patient should be given simple verbal instructions:
Sticky sweets must be avoided.
Good oral hygiene is important -keeping the appliance and the mouth clean
If the appliance breaks or causes discomfort or trauma to the cheeks or tongue, the
patient should not wait for a routine visit but contact the doctor for an earlier
appointment.
Where the patient is a child, the parent should be brought into the surgery so that
the instructions can be repeated.
A printed information sheet on the use of the appliance should be given to the patient
to take home
A further appointment should be made for the patient to be seen in approximately 2-3
weeks' time.
22. Difficulty in fitting an appliance
The wrong appliance
In a busy practice or laboratory incorrect labelling can occur. It is possible that the
wrong appliance has been returned.
Inadequate impression
An impression, which has been removed from the mouth before it is completely
set, will be distorted.
Inadequately extended impressions or those with air blows of any size may
present problems
23. Anticipation of extractions
If the technician has removed from the model the teeth which are to be
extracted, and the appliance encroaches on this area, it will not fit without
modification until the extractions have been carried out.
Eruption of teeth
The eruption of palatally placed teeth, particularly upper second premolars, can
cause problems.
This usually occurs when there has been a delay in fitting the appliance since the
impression was taken.
24. Delay since the impression
Forward movement of the buccal segments following orthodontic extractions or
natural loss of deciduous teeth may interfere with fitting.
Excessive undercut
Undercuts need to be blocked out on the model before the appliance is made
because subsequent trimming may weaken the appliance unduly.
25. Difficulties with clasps
Check the design of the Adams' clasps and ensure that there is adequate
undercut on the first molars.
Over trimming of the model during construction can make the clasps so tight
that insertion is impossible.
In adult patients, trimming is usually unnecessary and even to take the
arrowheads up to the gingivae may mean that excessive undercut is engaged.
26. Subsequent appliances
Occasionally a subsequent appliance will not fit because movement of the
teeth has occurred since the impression was taken.
This may result because the previous appliance was left active or because
the patient has ceased to wear it.
Either of these events can cause inconvenience and the latter can even
produce the situation where neither the new nor the old appliance will fit.
27. Subsequent visits
The appliance must be adjusted with care and good records need to be kept.
The patient should be seen 2 or 3 weeks after the appliance has been fitted and
then at monthly intervals.
Inadequate attention to detail at regular visits may mean that something is
overlooked and that progress is slow or erratic.
The acrylic or the occlusion may interfere with tooth movement, unintended
movements may be taking place or anchorage loss may be occurring.
Oral hygiene can also deteriorate, unnoticed, over the course of a few visits.
28. Preliminary discussion with the patient
Enquire whether the patient has experience any problems with the appliance since the
previous visit.
Avoid leading questions
Excessive looseness may lead the operator to suspect that the patient has developed the
habit of moving the appliance up and down with the tongue.
If you conclude that the appliance has not been worn as directed. raise the matter
directly
The operator should then remove the appliance noting any degree of activation
remaining in the springs.
29. Changes in the occlusion since the last visit
It is good practice to measure and record changes in tooth position at each visit rather
than simply entering a verbal comment. A simple measurement is often sufficient
Generalized palatal inflammation may reflect the need for more thorough oral
hygiene.
Heaping up of the gingivae around the teeth being moved indicates that the appliance
has not been trimmed away adequately.
30. Anchorage
It is important to take further measurements at each visit to confirm that
anchorage loss is not occuring.
Where only one arch is being treated it is usually easy to use the other arch
as a reference.
In the case of upper canine retraction a measurement of overjet should be
taken and any increase in this is usually a warning that anchorage is being
lost
The molar relationship will also become more class II. When lower arch
extractions have been carried out assessment can become more difficult.
31. If marked anchorage loss has occurred, changes in the relationship of the two arches will
become noticeable.
When unwanted movement is discovered, corrective action should be taken at once.
If the active components are exerting too great a force this must be reduced.
Space requirements should be reassessed. If there is space to spare some loss of anchorage
may be accepted
32. Lack of satisfactory progress
Is the tooth free to move?
If the baseplate is in contact with the tooth, it should be cut away
sufficiently to ensure that further obstruction does not occur.
Make certain that an unerupted tooth or retained root has not been
overlooked.
33. Has the correct force been applied?
Check that a spring is located correctly and on the right side of the tooth when the
patient inserts the appliance.
Make sure that the spring is adequately activated
The use of heavy pressures will cause hyalinization within the periodontal
ligament and delay resorption, so light pressure should be maintained and the
patient should be warned that treatment will be lengthy.
In very rare cases, treatment may be prolonged by the presence of dense alveolar
bone
34. Has the appliance been worn as instructed?
It is sensible to look for other signs of poor wear before discussing this with the
patient.
Difficulty in handling and inserting the appliance, speech problems, poor fit, lack
of attrition facets on bite planes and an absence of marks on the palate at the
periphery of the baseplate - all these point to lack of fulltime wear.
Careful questioning of the patient may elicit that it is left out for meals, at night,or
at school.
35. Activation
For a single rooted tooth a force of 30-40 g is appropriate to produce
controlled movement with minimal tipping.
The thickness and length of the spring will determine the amount of activation
necessary to produce such a force, but a desirable activation is roughly one-
third to one half a unit (about 3 or 4 mm).
If more activation is attempted the appliance may be difficult to insert
correctly.
The chance of the spring being wrongly positioned is increased and the spring
is also more prone to damage.
36. A thicker or shorter spring may easily produce a force that is too heavy
Unless the patient attends frequently this produces slow movement and
provides a temptation to over activate the appliance.
Results in pain ,anchorage slip and perhaps unwanted tilting of teeth
If the operator has access to a force gauge of the 'Correx' type,it is possible to
check the spring pressure being applied
37. The labial bow
The general principle of avoiding existing bends during activation and of
carrying out the adjustment at different points still applies.
Where the incisors are irregular it may be necessary to combine careful
selective grinding of the palatal acrylic with activation of the labial wire.
The wire may also be kinked to bring pressure to bear on a particular tooth
and so help in obtaining alignment.
38. Labial bow is activated by reducing the size of the loops. Each side is dealt
with individually by holding the loop in the pliers and flexing the bow mesial
to them .
It will be necessary to re-adjust the vertical height of the labial wire because
closure of the loops will cause this to move occlusal.
Flex the loops inward or outward as required to avoid trauma to the alveolus or
lip respectively
39.
40. Headgear
It is important that headgear should fit snugly and be comfortable
It must be kept clear of ears.
The straps themselves should be broad so that the load is well distributed.
The inner bow must match the arch form and length .It should lie a few
millimetres labial to the upper incisors and be at the level of active lip lne.
Its length can be adjusted at the U loop.
41. With removable appliance the main concern is that the direction of pull does not tend to
unseat the appliance.
For active retraction of buccal segments ,wear for 12-14 hrs out of each 24 hrs
42. Patient motivation and monitoring are crucial to its successful use.
The patients are at risk if the facebow becomes dislodged from the appliance.
This can happen if the facebow is removed while still attached by elastics to headcap,
whether intentionally by the patient or inadvertently during play.
If a detachable facebow is used then the ends that engage the tube on the molar clasp
should be of the curved design.so that there is less chance of facial injury.
Safety headgear is available and is designed so that the hook attachment on the headgear
detaches when predetermined force level is exceeded.
43. Patient instructions
Regular wear of the appliance should be reinforced because the force applied is
intermittent ,patient’s initial acceptance of the appliance is difficult to achieve.
Proper counselling should be given.
Appliance should be worn during evening hours
Should be advised on the safety aspects of the appliance.
Headgear should not be used as a play toy.
44. When an extraoral appliance is fitted and demonstrated to a patient and parents a
warning of the potential risks should also be given.
Patients are advised to wear the appliance in the evening at home for the first 2
weeks after it has been fitted.
Provided it is being managed satisfactorily the patient is instructed to wear it while
asleep in addition to indoor daytime wear
A record of the adjustment and checking of headgear should be made in the patient’s
notes at every visit.
In headgear patients it is useful to ask the patient to keep a diary of wear.
It is important to ask to see the diary at each visit and to give encouragement or
praise in order to reinforce the patient's efforts.
45. Patient cooperation is the most important factor in the treatment of a case with
functional appliances.
Educate the patient and the parent with the help of audiovisual aids,the design of the
appliance and its mechanism of action.
Explain to them the results of a few treated cases with the help of study models and
photographs
Emphasize the duration of time taken for treating those cases,to prepare them to accept
the duration of treatment
They should be made to understand that even the best made appliance would not be of
any use,if the patient does not wear it or fail to follow the instructions.
47. The appliance is first inserted into the mouth of the patient and seated onto the
maxillary arch.
If there is any interference ,it would be generally due to presence of undercut
Selectively relieve them.
Once the appliance is seated on to the maxillary arch,Ask the patient to gently close the
mandible.
Explain to the patient that the appliance may fall off the mouth or will be discarded
subconsciously sometimes in early period of wearing the appliance during nights.
Reassure the patient,that they will get used to it.
48. On the first visit insert the appliance and give instructions.
Initially it is worn for 2-3 hrs in a day for 1st week.
Followed by night time wear and 1-3 hrs of day time wear for 2nd week.
The patient is recalled for check up on 3rd week.
Followed by check up appointments every 6 weeks.
Trimming according to the plan is started from 2nd visit once the patient
gets used to the appliance.
The patient activates Jackscrew at 2 week interval if incorporated in the
appliance
49. Trimming of the Activator
1) A finished activator is generally delivered untrimmed to the patient to
achieve maximum skeletal changes.
2) In subsequent visits trimming is carried out to create guidance planes for
selective eruption of the teeth. The desired tooth movements with the
activator are-
a. Maxillary posteriors –buccaly,distally and Oclusally.
b. Mandibular posteriors-buccaly,mesially and occlusally.
c. Maxillary anteriors –distally(to allow retraction)
50. 3)Mandibular anterior region is not trimmed, in fact teeth are capped
with acrylic to prevent proclination.
4) Untrimmed gingival portion guides the teeth buccally .
51. Procedure
Materials
1 Long narrow tapered acrylic bur
2 Micromotor
3 Glass marking pencil
i) Mark the areas to be trimmed with white marker pencil
a)Maxillary posteriors-occlusal 1/2 of distal embrasure
b) Mandibular posteriors occlusal 1/2 of mesial embrasure
c)The acrylic resin behind maxillary incisors trimmed up to the
alveolar region to allow retraction of the anteriors
52. Ii) Confirm that all marked areas are trimmed, unmarked areas
will be appear shiny.
Iii) Place the activator on the mounted cast; confirm that there is
no obstruction to desired tooth movement as mentioned
previously
iv) Properly trimmed activator shows “honey comb” appearance
on side view.
v) finally trimming is checked inside the mouth.
54. Clinical management
1. After insertion of the appliance, a written appointment should be given in a
week to check for sore spot.
After this, appointment at 4-6 weeks interval are quite adequate.
In the average case, one year to 1 1/2years would be reasonable estimate of
the time needed to achieve correction.
2. The same appliance is worn during retention and is worn only during
night.If correction was achieved very rapidly, day time wearing should not be
abandoned at once.
55. The appliance is worn gradually less and less frequently in night.
The patient must be instructed to wear the appliance more frequently again if after an
interval a slight muscular tension is felt when the appliance is inserted.
Relatively few problems are encountered in handling of bionator.
The bionator is considered by many to be best type of functional jaw orthopaedic
appliance because of its relatively simple nature.24 hr wear makes it better appliance
to achieve correction and prevent relapse.
57. clinical handling
Timing of treatment
According to Frankel the optimum time to start treatment is the transitional
phase from early to late mixed dentition when child is 7-81/2years old.
Patient cooperation is key to success in FR treatment:
It is important to realize that FR works only if it worn during the day and
successful muscle training can be achieved only if it is carried out
gradually.
58. 2 ) Appliance delivery
All margins are checked for smoothness .Particular attention should be paid that the
labial pads of the FR are constructed properly and are tear drop in shape in cross
sections.
-It is imperative that the appliance be anchored in the maxilla, when used to change
mandibular postural position.Hence check if the separation is sufficient between the
teeth to cross over wires.
In mixed definition the seating grooves cut in cast have to be replicated in the patient
mouth using a diamond disk or cylinder.
59. Notch the distal surface of the second deciduous molars .But first
permanent molars not to be notched.
-To check the appliance fit:Place 2 index fingers under the inferior aspect of
vestibular shields and push the appliance vertically upward, this is done to
check if the cross over wires are properly seated in maxillary dentition.
Check for overextension of vestibular shields in posterior and canine
regions.The peripheral portion of the shield should properly contact the
sulcus tissue without blanching it.
The shields should be away from the alveolar mucosa and dentition only as
much it is required to achieve the necessary expansion.
60. Most likely place of tissue impingement is the area of lower margins of lip pads.If
blanching is seen in the mandibular anterior sulcus trim the lip pads(lower margins)
and polish again.
This can be avoided by placing lip pads correctly in the vertical direction, if not placed
correctly the lower margins tilts forwards resulting in soreness and ulceration of the
corresponding regions of the lower lip.
It is important to check the wax up of lip pads properly to prevent improper slant as
faulty position of lip pads, can rarely be corrected by grinding adjustments during
delivery and may distort the appliance,
61. Instruction to patient
Instruct on how to put the appliance:
Child should hold the appliance in one hand and the cheek at the corner of
mouth with the other and rotate the appliance in on one side . Use of mirror
greatly facilitates appliance insertion.
The face should be palpated on the outside to make sure there are no sharp
edges sticking into the cheeks of the lip pads.
Encourage adaptation by asking the patient to pronounce his name out along
with the appliance in place few times.
62. The FR does not restrict tongue movement
Wearing the appliance:
successful treatment with FR is only possible if the appliance is worn during the
day with lips together.
This concept needs to be understood both by the parents and the child.
The parents must remind the child to wear the appliance before leaving school.
63. The sheet of paper /tongue blade should be kept between the lips during T V
watching and homework.
Whenever appliance is not in the mouth it should be kept in a container with water
for safe keeping
Orthopeadic training with FR is started slowly.
For first two weeks wear 1-3hrs in the afternoon only
This hour depends upon type and severity of malocclusion.
Patient usually get adjust to FR 3 more easily than FR I and FR 2.
64. Recall visit
First check up after 2 weeks of delivery where one checks for
1. Stripping of gingiva
2. Ulceration and violation of muscle attachment
3. Excessive tissue redness
Presence of these indicates that they are not properly extended.
Speech impairment with FR is minimal but if it continuous either patient
is not wearing the appliance or insufficient lip oral training
In this cas,speaking exercise are encouraged
2 weeks later patient should wear appliance for 4-6 hrs
65. 2. It takes at least 3-4 months for patient to adapt full time wear.
Night time wear should not be rushed into, because in presence of
mandibular retrusion the jaw will open down and back during sleep the
lingual shield will then slide over the mandibular anteriors and tip them
labially.
In class III, FR 3 can be worn at night after 3-4 weeks except in case of
hyper divergent face pattern,which requires intensive lip seal training.
66. FR3 to be worn at night only when progress in training of sealing muscles is
identified.
Check after every 4 weeks for:
1 Mucosa of the vestibule
2 Stabilization of appliance in maxillary arch
3 Cross over wires not moving in interdental tissues.
67. Appliance adjustment
With FR I it may be necessary to bend the canine loops occlusally and the
molar rests gingivally to prevent irritation on the interdental papillae when
deciduous molars are lost and premolars erupt.
Labial bows can be activated to retract the maxillary incisors and to close
spacing between anteriors
.Lingual wires may need to be bent to protrude the mandibular incisors
which are inclined lingually.
In severe mandibular retrusion the lingual shields/lip pads of FR1 ,FR 2
may have to be advanced forward.
68. Treatment progress:
Check after 8-12 weeks.
After 2 months of appliance wear ,expansion of arches should be apparent.
Transverse distance is measured between deciduous molars and first
permanent molars of maxillary and mandibular arches.
Likewise changes in :
Overjet
Overbite
Sagittal improvement in class II relation is measured
69. If patient is very cooperative with full time wear, within 6 -8 months change
in relation from distoocclusion to neutroocclusion will be noticed.
Patient will have difficulty in positioning the lower jaw posteriorly.
This indicates that the new postural performances pattern of the suspending
musculature has been established.
Concomitant decrease in mentalis muscle hyperactivity should be noticed.
70. FR worn as retainer
Use of FR appliances retainer is particularly in those cases where the muscle
training achieved in active treatment phase is not entirely satisfying.
FR still being used as retainer on few hrs in the afternoon and at night.
2hrs in afternoon,6hrs at night for 6 months
Only at night -1 yr.
After active treatment phase if certain tooth positions are not where they
should be they can be altered with fixed appliance.
72. Clinical handling
Appliance delivery
Before delivery of twinblock –
1)Check whether the appliance is correctly fabricated and amount of activation
introduced.
2) Patient is shown how to place appliance in mouth properly.
3)Check fit of appliance-by trying upper and lower components separately
4)Adjust the delta clasps and ball clasps.
73. 5)Both parts of appliance should be anchored in place and should not float loosly
in mouth.
6)It should be confirmed that the patient closes consistently on inclined planes
with the mandible protruded in its new position.
7)Overjet should be measured with mandible fully retruded and checked at
every visit to monitor progress.
74. Instructions to the patient:
1) Appliance should be worn full time ,especially during eating ,and removed only
for cleaning.
2) At first the appliance will feel large in mouth ,but within a few days it will be
comfortable and easy to wear.
3)For first few days , speech will be affected ,but will steadily improve and should
return to normal within a week.
4)Expansion screw should be turned one quarter turn per week.
75. Adjustments
STAGE 1: ACTIVE PHASE
1) appliance fitting
- Patient should be able to bite comfortably in protrusive bite with inclined
planes occluding correctly.
- Important to relieve appliance slightly lingual to lower incisors to avoid
gingival irritation during first few days.
- Labial bow ,if present ,should be out of contact with upper incisors.
76. 2) Initial adjustments(After 10 days to 1 week)
Initial discomfort should have resolved.
Patient should be biting consistently in protruded position.
Upper screw turned one quarter turn/weeks.
In treatment of deep overbite-upper bite block trimmed clear of lower molars
leaving a clearance of 1-2 mm.
If patient unable to position the mandible comfortably in protruded position ,the
angulation of inclined planes reduced to 450.
77. 3)After 4 weeks
-Positive progress should be noted in facial muscle balance
-Screws should be checked
Labial bow adjusted so that it is out of contact upper incisors
-In treatment of deep overbite lower molars should be relieved
4)Routine adjustment –time interval 6 weeks
-Check for correction of distal occlusion
-Check for upper arch expansion
-Trimming should be continued until all occlusal cover is removed from upper
molars to allow lower molars to erupt completely into occlusion.
78. Trimming of twinblock- Management of deep overbite
Overbite reduction achieved by trimming occlusal blocks on upper appliance ,so as
to encourage eruption of lower molars.
Increase lower facial height and to improve facial balance by controlling the vertical
dimension.
Trimming initiated at start of treatment so as to permit eruption of lower molars.
Upper bite block trimmed occlusodistally to allow lower molars to erupt.
Trimming continued progressively at each visit- permitting only a small vertical
clearance of 1-2 mm over lower molars to allow their eruption.
79. This sequence of trimming does not allow tongue to spread laterally between teeth to
prevent eruption of lower molars ,and results in a more rapid development of vertical
dimensions.
Normally, it takes 6-9 months for molars to erupt into occlusion. Mandible should be
supported in a protruded position throughout trimming sequence.
After molars have erupted into occlusion,final adjustment at end of twinblock stage
aims to reduce the lateral openbite by trimming the upper occlusal surface of lower bite
block over the premolars by 2mm.
80.
81. Occlusal height of upper premolars is maintained by interdental clasps that
effectively prevent their eruption
STAGE 2 :SUPPORT PHASE
Upper appliance with anterior inclined plane
Retention
Treatment followed by normal period of retention, after occlusion is fully
established.
Appliance wear can be gradually reduced to night time wear
82.
83. Time table of treatment
Average treatment time:18 months
Active phase-6-9months to achieve full reduction of overjet to normal incisor
relationship and to correct distal occlusion.
Support phase-3-6months for molars to erupt into occlusion and for premolars to
eruption
Retention-9 months ,reducing appliance wear when position is stabilized.
84. Generally ,each time a patient presents during treatment, the treatment plan
has to be reconsidered in light of the treatment response and some elements
of the original problem that might have been overlooked.
In the contemporary paradigm,the orthodontist no longer makes decisions
alone but now does so jointly with the patient and /or parent
85. CONCLUSION
Patient management is an important criteria in achieving
clinical results
Efficient patient management helps to cultivate a good-patient
doctor rapport .
If expectations of both the patient and the doctor are realistic
then treatment result will be a rewarding experience for both
86. Take home message
We should realize that from a patient’s or parent’s perspective,
the appearance and psychosocial benefits of orthodontic
enhancement often have higher values than occlusal outcome of
treatment.
Stated bluntly, an orthodontist who views his role in society
simply as one who corrects dental occlusion is clearly missing the
larger picture.
87. Reference
Removable Orthodontic Appliances –K.G Issacson,J.D.Muir,R.T.Reed
Orthodontics Current principles and techniques-Graber. Vanarsdall. Vig(5th edition)
Dentofacial Orthopedics with functional appliance-GRP (2nd edition)
Editor's Notes
both as
and also to
Well-trimmed current study models are most important.
This enables the form of the alveolar process to be assessed.
This ensures that any asymmetry of the arches will be recognized.
Good radiographic records are necessary to
Should there be any doubt about the condition of the incisors or any possibility of supernumerary teeth being present.
For the majority of cases that are suitable for treatment with removable appliances
Where limited tooth movement is being carried out and all successional teeth have erupted, it may be possible, in some circumstances, to carry out treatment without radiographs.
One advantage of intraoral photographs is that they will demonstrate any possible decalcification which are present at the start of treatment which may be a useful record in case of any questions arising at the end of treatment.
Treatment will be better controlled and more rapidly completed if a separate appliance is used for each group of tooth movements
At the time of fitting pick up the applianceand run the fingers over the baseplate -particularly the fitting surface - checking forany sharp areas Air bubbles on the model
can produce roughness of the acrylic but such areas can be quickly smoothed, as can any sharp ends of wire.
drawing attention to the need to take care not to distort any of the active parts of the appliance during its insertion and removal.
Frequently, however, the operator is presented with an appliance on which the clasps are faulty and adjustments may be necessary.
These faults can be corrected in most cases by a combination of bends at two points.
Take as an example a clasp that is found to have an arrowhead pushing ihto the gingivae(Figure 10.8a). The wire can be bent at point X to move the arrowhead occlusally (F). The height will be corrected but the adjustment will also have the effect of moving the arrowhead away from the tooth. A bend can then be placed at point Y to compensate for this
If the arrowhead grips too far occlusally it can be moved buccally by an adjustment at point Y. A further adjustment at point X will then bring it into contact at the correct position).
Poor retention may be due to a conically shaped tooth, which offers little undercut. This is especially common when second molars are
being clasped.
This will merely interfere with the passage of the wire across the embrasure and prevent full seating of the appliance.
On occasion, slight initial trimming may be necessary to allow insertion, but beyond this some adjustments to the baseplate may also be necessary.
. For example to permit a buccally placed canine to move into line as a premolar is being retracted.
Before activating springs the labial wires, loops and buccal springs should be adjusted if necessary so that they lie at the correct height and do not traumatize the cheeks, lips and gingivae.
During fitting, any anterior clasp on the incisors will generally be engaged and the position of the springs checked before upward pressure is applied to the palatal acrylic with a finger or thumb .
Wear during meals is especially important. Particularly if bite opening has to be achieved or if the teeth are being moved across the bite
The patient should be instructed to wear the appliance full time, for meals and as far as possible for sports.
If, on occasion, circumstances do not permit this then the appliance should atleast be removed from the mouth and rinsed under a tap.
If it does prove necessary to remove the appliance from the mouth other than for cleaning, for example during contactsports or the playing of a wind instrument. the
patient should be instructed to
The most difficult adaptation is to accept the wear of the appliance at meal times and this may take several days to accomplish. The patient should be encouraged
to persevere until this has been achieved
Chewing gum - other than one especially formulated for denture wearers - will adhere to the acrylic.
The patient should continue to wear the appliance for some hours each day if possible to maintain its fit. If the appliance cannot be worn it should be kept moist
This not only informs the parent but also allows reinforcement of the instructions to the child. The printed instructions should be given to the patient only after verbal instructions.
There are several reasons why a new appliance may not fit.
The technician should be asked to leave all existing teeth on the model during appliance construction, except in cases where wires are to be positioned across extraction spaces.
Unless the embedded parts of the wirework override the erupting teeth, the acrylic can be trimmed away, but if the wireworkis in the way, this provides a considerable difficulty.
The eruption of an instanding tooth should be anticipated when designing the appliance.
Wire loops, which lie close to the gingivae, take no account of the path of insertion so that they may impinge on the mucosa as the appliance is seated. Careful adjustment of the appliance can usually avoid this.
Successful management of orthodontic treatment depends upon careful assessment at each visit so that lack of progress or unwanted tooth movements can be recognized early and remedial action is taken.
This merely encourages an affirmative answer. even if the patient has not been cooperating
.it is easy to see whether it is being correctly worn and whether all springs are correctly positioned
Look into the mouth before the appliance is removed. The fit of the appliance is then easily assessed.
The fitting surface of the appliance will give some clue to oral hygiene but in addition the teeth, gingivae and oral mucosa.
Newton's third law of motion tells us that every force has an equal and opposite reaction.
When teeth are being moved the reactive force will be transmitted through the appliance . and will affect other teeth which are themselves capable of movement.
. Where the obstruction is due to occlusal interference
the bite plane may need to be thickened by the addition of cold-cured acrylic
The operator can ask the patient to demonstrate turning and the screw can be turned back to check that the number of turns corresponds with that expected.
Although the problem is rare, a similar situation can arise where a tooth, often an upper canine, is buccally displaced into the cortical plate. The bone surrounding the root is dense and lamellar and if the tooth is moved parallel to the line of the arch progress will be slow. Such a tooth should be moved into the line of the arch by the shortest path and then retracted through the cancellous bone of the alveolar process.
Provided that the appliance has been correctly adjusted lack of tooth movement is usually due to inadequate wear.
By giving the patient a target number of hours to be achieved per week, motivation can be improved
Where cooperation is not adequate, all that can be done is to emphasize to the patient (and parent) that failure to wear the appliance as instructed can only delay treatment and prejudice the result
The orthodontist should always have In mind the problem of muscular adaptation involved in this kind of treatment.Therefore the length of retention period may vary from 6-1 year,or even longer.
lip.This faulty position may also cause the upper border to tilt towards gingiva and opens mouth resulting in stripping of gingiva.
Hence it is best to reacrylize the lip pads.
.Hence speech impairment is only minimal.During speaking the vestibular shields loosen the tight musculature and this facilitates musculature to adapt to the appliance.
. d.Patient is made to read out paragraphs from books and record it in a tape which can be useful tool to examine speech impairment
The patient should not be allowed to wear the appliance at night because the mucosa and muscles have sufficiently adapted to wearing the appiance during the day.
5) Initially the appliance should be removed at time of eating.However ,the importance to eat with the appliance in mouth should be stressed.This enhances effect of functional forces.
-Patient should be now wearing the appliance comfortably and eating with them in position.
Patient motivation is reinforced.
-confirmed by reduction in overjet measured intraorally with mandible fully retruded
to encourage selective erupton of posterior teeth to increase vertical dimension.
To maintain adequate inclined planes to support the corrected arch relationships the lower bite block is shaped into a triangular wedge distally in contact with the upper block.
