Orthodontic Treatment - Treatment of Orthodontic Problems

CingSianDal 9,433 views 109 slides Jun 01, 2018
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About This Presentation

Orthodontic Treatment - Treatment of Orthodontic Problems
Copyright by Orthodontic Department, UDM


Slide Content

Orthodontic treatment
Treatment of orthodontic problems
K.Thein

Treatment of orthodontic problems
Orthodontic problems
Nonskeletal orthodontic problems
Alignment problem, dentitional problem, and
space problems (crowding / spacing) without
skeletal dysplasia.
Skeletal orthodontic problems
Size or positional malrelationship of skeletal
structures in all three planes of space
(sk-II, sk-III, sk crossbite) usually associated with
dental problems.

Treatment
Treatment in preadolescent children
(Mixed dentition treatment)
- Non skeletal orthodontic treatment
- Growth modification treatment
Treatment in adolescence and adult
(Early permanent and permanent dentition)
- Comprehensive orthodontic treatment
- Camouflage treatment
- Orthognathic surgery
- Combination of above treatments

Timing of treatment
Early or Preadolescent treatment
Mixed dentition treatment
Adolescent and
Adult treatment
Nonskeletal orthodontic treatment
Skeletal orthodontic treatment
-Growth modification treatment
Comprehensive orthodontic treatment
- In adolescence (early permanent dentition)
- in adults:
- young adults
- older age group
Camouflage treatment
Orthognathic surgery
Combination of above treatments

Treatment of nonskeletal orthodontic problems in mixed
dentition or preadolescent dentition (Early treatment)
Advantages
1. Possibility of achieving better results
2.Some forms of treatment can only be done at an early age
3.Control of deleterious habits is easier
4.Psychological advantage
5.Young patients are more cooperative and attentive

Disadvantages
- Difficulty in defining goal for early treatment
- Improper early treatment can be harmful
- Diphasic treatment may lengthen the total
treatment time

Reason for failure of early treatment
- When there is no clearly defined goal
- When there is no clear reason for starting
treatment

No one has the right to begin treatment -
- without clear definition of treatment goal
- without a reasonable understanding of
the treatment process
- without reasonable expectations of
success of treatment

TREATMENT OF CROWDING
IN
MIXED DENTITION
K.Thein

THE DENTAL CROWDING.
The dental crowding was described as the difference
between the space required for the perfect alignment of teeth in
the arch and the space available in that arch – that is , the space
discrepancy.
Thus, crowding can be described as an expression of an
altered tooth / tissue ratio or as a dentoalveolar disproportion.

CAUSES OF CROWDING
Evolutionary
A trend toward a reduced facial skeletal size without a
corresponding decrease in tooth size. ( Hooton )
Hereditary
The result of interbreeding in ethnic groups who were
physically dissimilar. ( Brash )
Environmental
Loss of arch length caused by caries, early loss, delayed
eruption, etc ( Barber & Moore, Lavelle & Spence )
Conflicting evidence exists regarding the part played by the
tooth size and the part played by the arch dimension.

Crowding could result from-
Lack of adequate space for the alignment of permanent teeth.
Causing an erupting permanent tooth to be deflected from its
normal position in the arch.
Interference with tooth eruption.
A condition preventing the permanent teeth from erupting
normally.
eg. Early loss of deciduous teeth, supernumerary teeth,
ectopic eruption, delayed eruption etc.

Clinical Features of Crowding
In permanent dentition,
Actual crowding
Potential crowding

Actual crowding. (clinically evident crowding)
The incisor teeth remain upright and well positioned over
the basal bone of the maxilla and the mandible but the teeth
are rotated or tip labially or lingually

Potential crowding. (no clinically evident crowding)
The crowded teeth align themselves at the expense of lip,
displacing the lip forward and interfering with the lip
closure. The incisors are proclined and off the basal bone

Lip protrusion and crowding

Clinical Features of Potential Crowding
In mixed dentition,
- Irregular position of erupting permanent central and lateral
incisors
- Early loss of primary teeth with drifting and tipping of adjacent
permanent teeth
-Early loss of primary canines
- premature resorption of the root of primary canine in X-ray

Irregularly erupted permanent central and lateral incisors

Early loss of primary mandibular canines with drifting
and tipping of adjacent permanent teeth and primary molars

Early loss of primary maxillary canines with drifting of
permanent lateral incisors and primary molars

Early loss of mandibular left primary second molar with mesial
drifting of first permanent molar

Lack of space for the eruption of permanent teeth due to tooth
size jaw size discrepancy.

Patient selection (Who need treatment and by whom)
 Treatment for children with moderate crowding problems can
be safely provided in general practice.
 Moderate problems are those consist entirely of dental problems
without skeletal dysplasia ( skeletal pattern I ) and crowding less
than 4 mm. (Non skeletal orthodontic priblems)
 Careful facial analysis is required to exclude severe problems.
 Children with severe problems are best treated with two phase
treatment.

It was said that –
When Columbus sailed to America………
he didn’t know where he was going!
When he got there,
he didn’t know where he was!
When he returned to Europe,
he didn’t know where he had been!
However, since Columbus lived prior to the invention of
modern navigational instruments, he can be excused.
(TM Graber)

The goals for early treatment.
To allow normal eruption of permanent teeth by
preventing teeth from drifting and reducing space.
To create space in the dental arch for the eruption and
alignment of permanent teeth.

- There is no guarantee that any orthodontic therapy will
proceed as planned and achieved every treatment goals.
- Early treatment is most likely to fail when there is no clear
reason for starting and no well-defined goals and strategies.
- One may be tempted, when confronting a malocclusion, and
started treatment without discriminating thought or plan.

Treatment in mixed dentition should begin only when….
The treatment goals are clearly defined.
The treatment process is planned
The expectation of the success of treatment is
predicted.

Treatment planning
 Treatment planning depends on the magnitude of
dentoalveolar discrepancy.
 Various methods may be used to predict the size of permanent
canine and premolars (Mixed-dentition space analysis)
 Comparison of space available and space required quantifies
dentoalveolar discrepancy.

Space
available
Space
required
Compare
Space excess
OK
Space deficiency

One half of the
mesiodistal width + 10.5 For the estimated width of
of the four lower incisors mandibular canine and
premolars in one quadrant
+ 11.0For the estimated width of

maxillary canine and


;
premolars in one
quadrant
Mixed dentition prediction

What you should put first in all the practice of
our art is how to make the patient well; and if
he can be made well in many ways, one should
choose the least troublesome
Hippocrates
The objective of treatment planning is to design a
strategy to address the problems with maximum
benefit and minimum cost and risk

Mixed dentition treatment

Mixed dentition treatment
The primary teeth are in function from the time its eruption
until all the permanent teeth has erupted.
During the primary dentition and in the mixed dentition
period, the primary incisors and more frequently the primary molars
are likely to be decayed.
Interproximal caries or premature extraction of primary
molars during the early mixed dentition period (12CDE6 stage)
would result in the loss of arch space due to mesial migration of first
permanent molar or distal tipping of permanent incisors.
Unless appropriate mixed dentition treatment has not been
given in time, to prevent space loss or to regain space, there will be
localized crowding in the premolar and canine region.

Contd:
Treatment of localized crowding, late in the permanent
dentition usually necessasitate extraction of permanent tooth and
require complicated bonded or fix appliance.
Mixed dentition treatment given at an appropriate time,
has the advantage in that –
- it obviate the need for permanent tooth extraction
- it require less complicated treatment technique
- it allow the more natural growth and development of the
dental arch
- it has more stable result.

Treatment options
Space maintenance
Space regaining
Space management
Expansion / Extraction
Serial extraction

Space Maintenance
Localized crowding.

Space maintenance
Defined as the preservation of spaces left by the
primary incisors, primary canines, primary molars and
sometimes the primate spaces
Space maintenance treatment avoids the future
crowding and allows the normal eruption of developing
permanent teeth.

Indications for space maintenance treatment
- Missing primary teeth with no space loss
Early loss of primary canines and molars where
there has been no space loss or the space is adequate for the
eruption of permanent successors.
- Following the completion of space regaining treatment.
Prerequisites
The permanent successors (the premolars and canines) are
present and in correct developmental position.
The permanent successors would not erupt within six
months period.

Treatment techniques
Treatment techniques involve either fixed or removable
Band and loop space maintainer
Partial denture space maintainer
Holding arches
Lingual or palatal holding arch
Transpalatal holding arch
Nance holding arch
Distal shoe space maintainer

Band and loop space maintainers.
Unilateral fixed type appliance indicated to maintain the
space of primary first or second molar.
It consists of band and loop wire. The teeth for banding must
be fully erupted especially if the first permanent molar is to be
banded. Retention may be difficult if deciduous molar is to be
banded.
Loop wire must be wide enough faciolingually to allow
eruption of premolars and have adequate strength.
The loop portion of wire should lie above the contact area
and along the marginal ridge without interfering the occlusion.

Partial denture space maintainers.
Bilateral posterior space maintainers.
When more than one tooth has been lost, especially if the
permanent incisors have not yet erupted, to maintain space and to
replace function.
Replacement of anterior teeth, for esthetic function, in
conjunction with posterior space maintenance.
Patient compliance is needed for its effectiveness.
Therefore good retention of the denture is required. Failure to wear
the appliance leads to space loss.
Proper oral hygiene and regular cleaning of the appliance is
important.

Holding arch
Lingual arch space maintainers.
Indicated when multiple posterior teeth are lost and the
permanent incisors have erupted.
Consists of bands usually on the first permanent molars and
the lingual arch wire contacting the cingula of the incisors.
Prevents mesial movement of the posterior teeth and lingual
movement of the anterior teeth.

Contd-
The lingual arch wire should be placed to rest on the cingula
of the incisors approximately 1 to 1.5 mm off the soft tissues.
Should be stepped to the lingual in the canine region and
remain away from the primary molars and the unerupted premolars.
Problems include distortion, breakage and trauma to the
lingual gingiva.
Not suitable to use in upper arch with deep overbite.

Lingual holding arch (maxilla)

Lingual holding arch (mandible)

The Nance holding arch.
Bands on molars with the lingual arch wire inserted into
the acrylic button that contacts the anterior part of the hard palate.
Not as good as the lingual holding arch in space
maintaining capacity. More suitable if the palatal vault is deep.
Frequent problems include- space loss, soft tissue irritation
and hypertrophy if associated with poor oral hygiene.

Band on first molar
Palatal arch wire
Acrylic button
Nance holding arch

Transpalatal holding arch.
Bands on molars and the arch wire runs across the palatal vault
avoiding contact with the palatal soft tissue.
Reduce the molar mesial movement by preventing molar
mesiolingual rotation.
Indicated when the primary molars are lost on one side with
intact arch on the upper.
Space loss might occur despite the use of transpalatal arch
when both molars were lost bilaterally.
Problems include – displacement of molars if the wire is not
remain passive.

Transpalatal holding arch

Distal shoe space maintainer.
Appliance of choice when primary second molar is lost
before the eruption of first permanent molar.
Consists of metal or plastic guiding plane along which the
permanent molar erupts. The guiding plane must extend into the
alveolar process so that it contacts the permanent first molar
approximately 1mm below the marginal ridge at or before its
emergence from the bone.
The guiding plane is attached to the band on first primary
molar (fixed type) or inserted into the acrylic partial denture.
(removable type)
Careful positioning is required for the exact location of
guiding plane to ensure the eruption of first permanent molar.
Contraindicated in children who are at risk for subacute
bacterial endocarditis and immunocomprimised.

Space regaining.
Localized crowding

Space regaining
Space regaining is the restoration of arch length by
relocation of permanent teeth that have drifted into space
previously occupied by the primary teeth and the maintenance the
space thus gained.
Thus the space regaining procedure includes-
- restoration of arch length (space regaining) by distal
tipping of molars and labial tipping of incisors.
- maintenance of space thus gained (space maintenance)

Indication
- Localized space loss up to 3- 4 mm .
Space may be regained up to 4 mm if the loss is
unilateral and 3 mm if bilateral.
- Space regaining is more easier in maxilla than in
mandible.
- Choice of appliance depends on cooperation of the
patient, site ie maxilla or mandible and the tooth movement
required.

Techniques
Removable appliances
Using springs with various designs
Fixed appliances
Active lingual arches
Lip bumber
Utility arch with bonded brackets
Bonded brackets with closed coil spring
Head gear.

Upper removable appliance to distalize the first permanent molar.

Lip bumper appliance

Lower removable appliance to distalize the molar

Lower removable appliance to distalize the molar

Modified Adam clasp to distalize the molar bilaterally

Generalized crowding.
Transient crowding

Transient crowding
 During the early mixed dentition stage the erupting
permanent incisors may be crowded and clinically
expressed as mild irregularity or rotation especially in
the lower arch. This is called transient crowding.
 The transient crowding is due to the presence of
relatively large permanent incisors and primary molars
at that particular age although, the ultimate space to
accommodate all the permanent teeth will be available.

Treatment
 No need to begin treatment if incisor crowding is less
than 2mm. The crowding can resolve spontaneously after
eruption of premolars and permanent canines.
 If treatment is considered needed, disking of
interproximal surface of primary lateral incisors and
primary canines as the permanent incisors erupt is all that
is required.
 However, disking of primary teeth should be reserved
for situations when more than 2 mm of crowding exist.

Generalized crowding.
Space management / supervision

Space management (Space supervision)
Management of the existing space, during the mixed
dentition period, to allow for the proper sequence of
eruption and alignment of permanent teeth and to correct
molar relation.

During transition from primary molars to permanent
successors there is enough space for the premolars and permanent
canines to erupt and the first permanent molars to move mesially into
class I relation due to the presence of Leeway space.
If tooth sizes are large relative to jaw size the premolars and
permanent canines would have to use the Leeway space in order to
erupt and align properly.
In such situation it is very important to prevent mesial
movement of first permanent molars or lingual tipping of incisors into
the Leeway space.
In addition adjustment of first permanent molar relation into
class I position is required since no Leeway space is available for
molar mesial movement.

Indication for treatment
In patients with generalized crowding
If space for the eruption of premolars and permanent
canines are just enough or discrepancy is zero, with no
allowance for the molar mesial shift and lingual tipping of
incisors.
Flush terminal plane (End to end) or mesial step (class I).
When it is doubtful, according to the Mixed dentition
analysis, whether there will be room for all the teeth.

The objectives of space management treatment is

- to prevent the mesial movement of first molars or lingual
tipping of incisors.
(to allow normal eruption and alignment of premolars and
permanent canine without further arch perimeter shortening)

- to maintain class I first permanent molar relation.
(since no Leeway is left for molar adjustment)

Prognosis
The prognosis for the space management is always
questionable.
Therefore, space management should only be carried out in
such cases that will have a better chance of getting through
the mixed dentition with space management treatment than they
will without.
Failure of space management treatment or misdiagnosed
space management cases that require extraction of permanent
teeth are more difficult to treat than gross discrepancy cases
because :
(1) more space closure is needed
(2) the patient’s cooperation often lags after the
planned interceptive procedure has failed.

Basic principles for space management
Space supervision is not begun until the mandibular cuspid
and first premolar show approximately one-quarter to one-third of
the root formed.
Primary teeth are extracted serially to provide an eruption
sequence of cuspid, first premolar, and second premolar in the
mandible and of first premolar, cuspid, and second premolar in
the maxilla.
An effort is made to keep the mandibular teeth erupting
well ahead of the maxillary.
Take care that a late mesial shift of the mandibular first
permanent molar does not occur.

Space management technique.
Early extraction of primary canines and disking of primary
molars to allow the permanent incisors, canines and premolars to
erupt and align.
Lingual holding arch is required from the time the primary
teeth are extracted until the end of transition into permanent dentition.
Correction of molar relation is required since the molars were
not allowed to shift mesially into the leeway space. This can be done
by:
- extraoral force to the first permanent molar
with headgear.
- lip bumper
- fix appliance treatment.

Mesial step (Class I) protocol.
The mesial step relation with crowding in mandibular arch.

Extraction of primary canines Incisor alignment

Extraction of first primary molar
and slicing of the mesial of the
second primary molar.
Eruption of primary canines in
correct alignment

Removal of the second primary
molar
Placement of lingual holding
arch before removal of second
primary molar

Flush terminal plane (End to end) protocol
Flush terminal plane with crowding in the mandibular arch

Removal of mandibular primary
cuspid and distal tipping of
maxillary first molar
Improved incisor alignment as
a result

Removal of first primary molar
and slicing of mesial surface of
second primary molar
Eruption of mandibular canines
into the arch

Placing lingual holding arch and removal of the second primary
mandibular molars.
Note the first permanent molars are in class I position.

Generalized crowding.
Arch expansion
Extraction of permanent
teeth

Discrepancy up to 4 mm.
Treatment possibilities include -
- reduce the size of the primary canines.
- extraction of the primary teeth.
- expansion of the arch.

Discrepancy 5 to 9 mm.
Extraction or non-extraction treatment possible.
Extraction vs Expansion
Decision depends on characteristics of patient and the
details of orthodontic treatment.
Patients with narrow “V” shaped arch.
Patients with large nose and chin.
Direction and amount of tooth movement required
Aesthetics.
Choice of teeth for extraction

Generalized crowding.
(Tooth size jaw size discrepancy)
Serial Extraction.

Serial extraction (Kjellgren), guidance of eruption (Hotz)
-Timed extraction of deciduous and, ultimately,
permanent teeth to provide space and to stimulate eruption.
-It is an interceptive procedure designed to assist in
the correction of tooth-size and jaw-size discrepancies.
-Therefore true hereditary tooth-size and jaw size
discrepancies must be differentiated from crowded
dentitions resulting from the factors that are more
environmental in nature.

Patient selection for serial extraction
Ideal conditions for serial extraction are –
True, relatively severe hereditary tooth size-jaw size
discrepancy.
Mesial step mixed dentition developing into class I first
permanent molar relation.
Minimal overjet relationship of the incisor teeth.
Minimal overbite.
Orthognathic facial pattern, or with slight alveolodentlal
protrusion

Prerequisite
All teeth present and in good developmental position,
particularly premolars and canines.
No caries at permanent incisors and first permanent
molars
Good oral hygiene

Diagnosis.
- Facial examination.
- Intra-oral examination
- Diagnostic records.
Diagnosis records.
- Radiographs.
Periapical or panoramic radiograph.
Cephalometric radiograph.
- Photographs.
Facial Photographs, intraoral photographs.
- Study models.
Properly articulated upper and lower models
for space analysis and to provide record.

Sequence of extraction.
C,D,4 sequence
Begins in early mixed dentition period, with the extraction of
primary incisors, followed by extraction of primary canines.
- To allow proper eruption and alignment of permanent
incisors.
Extraction of maxillary primary first molars. Best extracted
when there is half to two-thirds root formation on the first premolar.
- To stimulate or speed up the eruption of permanent first
premolars before the canines erupt.
Extraction of first permanent premolars.
- To provide space for the eruption of permanent canines.

The CD4 sequence of extraction in maxilla
-Correct maxillary incisor alignment and speed up the
eruption of first permanent premolars. Associated with lingual
tipping of incisors.
- The objective of serial extraction is to allow the eruption of
first premolars ahead of canines which will later be
extracted to correct crowding.
- The maxillary canines are the last tooth to erupt into the
oral cavity and also the developmental position of first
premolars in radiograph is usually much closer to the occlusal
level than permanent canines.
- Therefore, there is greater chance of first premolars to
erupt ahead of canines.
- Lingual tipping of incisors would result in more
aesthetically pleasing face if the patient has slightly convex
facial profile. However, it may have negative consequences
if the patient already has concave facial profile.

The CD4 sequence of extraction in mandible
The mandibular first premolars usually erupt ahead of canines
and the developmental position of the first premolars in radiograph is
much further away from the occlusal level than the position of
canines.
Therefore the C,D,4 sequence in the mandible has the greater
chance of eruption of canines ahead of first premolars, which would
make the extraction of first premolars difficult.
In addition, the lingual tipping of mandibular incisors,
associated with C,D,4 sequence, would increase the overjet and
exaggerate crowding in the maxillary incisors.
If this sequence is to be employed in the mandible, make sure
that the developmental position of first premolar is ahead of canine
and lingual holding arch, contacting the cingulum of incisors, is
required from the beginning of treatment.

The D,4,C sequence of extraction
This sequence of extraction may be used in maxilla. The
incisor alignment may not improve with the extraction first
primary molar. After removal of first premolar and primary
canines space may be available for correction of crowding.
This D,4,C sequence of extraction is especially suitable in
mandible where the permanent canines tend to erupt earlier than
first premolars. The extraction of primary first molars speed up the
eruption of first premolars. The premolars may be extracted, soon
after its eruption, to make space for the eruption of permanent
canines.
This sequence of extraction is less associated with lingual
tipping of permanent incisors in the mandibular arch.

Conclusion.
 Serial extraction treatment is not a panacea in all patients
who present with dental crowding.
 It is the treatment of tooth-size and jaw-size discrepancy.
Therefore, appliance treatment is almost always required to
correct individual tooth position and arch interdigitation
The whole treatment should include –
- sequential extraction ( serial extraction )
- mechanotherapy ( appliance treatment )
- retention.

Extraction in orthodontics

Background history
Extraction versus non-extraction
- Changing trends in extraction / non-extraction based treatment.
Edward Angle – every person had the potential for an
ideal relationship of all 32 teeth. Ideal facial aesthetics could be achieved
by expanding the dental arches so that all the teeth were in ideal
occlusion.(1890)
Rousseau- from an orthodontic point of view, a perfect
occlusion could never be achieved by the extraction of teeth.
Wolff- remodelling of bone could occur in response to
functional loading.(1900)
Angle reasoned that if teeth were placed in a proper
occlusion, functional forces transmitted to the teeth would cause bone to
grow around them.

Tweed, argued about the poor long term stability of expanded
dental arches. He retreated Angles cases by extraction of four first
premolars and claiming more stable occlusion after extraction based
treatment.
The extraction debate has continued, because-
-arch expansion has tendency to relapse
-extracting teeth does not guarantee future stability.
Therefore, each case should be properly analysed and planned
to give optimal stability and aesthetics.

Teeth were extracted in orthodontics for two
reasons –
- to provide space for the correction of
crowding.
- to correct anteroposterior relation of teeth.
(To correct overjet and molar relation)

The following factors should be considered when extraction
of teeth is required.
The quality of teeth.
The degree and position of crowding.
The alignment of teeth in the dental arch.
The molar relationship.
The age.

The quality of teeth.
Aesthetic quality.
Function requirement.
Condition of teeth
The degree and position of crowding.
Degree of crowding.
Extraction of teeth with greater mesiodistal
diameter provides more space.
Position of crowding.
Extraction of teeth nearer to the area of crowding
provides more space.

Alignment of teeth in the dental arch.
Severely displaced or malaligned teeth may be
extracted if the adjacent teeth provide good contact
relation.
Most commonly displaced teeth are maxillary
canines, mandibilar second premolars, ectopically
erupted tooth.

Molar relation.
Class I relation.
All first premolars or second premolars.
Class II relation.
Maxillary first premolars and mandibular second
premolars.
Class III relation.
Mandibular first premolars and maxillary second
premolars.

Class I
Extraction of 4s or 5s
Class II
Extraction of upper 4s & lower 5s
Class III
Extraction of upper 5s & lower 4s

The age.
Extraction of mandibular first permanent molar
(enforced extraction) should be best done at age eight and a
half to nine years.
Enforced extraction of maxillary first permanent molar
can be delayed up to fourteen years.
Extraction of maxillary first premolars should be done
when tip of the canine appeared in the mouth at about the age
of ten or eleven years.