Preventive

Preventive orthodontics is action taken to preserve the
integrity of what appears to be the normal occlusion at a
specific time.
Preventive procedures are undertaken in anticipation of
development of a problem.
For eg: extraction of supernumerary teeth before they cause
displacement of other teeth is a preventive procedure, while
their extraction after the signs of malocclusion have
appeared is an interceptive procedure.
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The following are some of the procedures undertaken in preventive
orthodontics:
•Parental education
•Caries control
•Care of deciduous teeth
•Management of ankylosed tooth
•Maintenance of quadrant wise tooth shedding time table
•Check-up for oral habits and habit breaking appliance if necessary
•Occlusal equilibration if there are any occlusal prematurities
•Prevention of damage to occlusion eg: Milwaukee braces
•Extraction of supernumerary teeth and space maintenance
•Management of deeply locked first permanent molars
•Management of abnormal frenal attachments

Education of parents
Should ideally begin before the birth of the child.
The expectant mother should be educated on matters such
as nutrition, to provide an ideal environment for the
developing foetus.
Should also be educated on proper nursing and care of the
child.

Should be educated on the difference between the physiological
nipple and the conventional nipple.
Conventional nipples are non physiological and do not permit
sucking by movement of the tongue and the lower jaw Rather they cause
sucking of the milk which later on lead to various orthodontic problems.
Physiological nipples on the other hand are designed to permit
suckling of the milk which more or less resembles the normal functional
activity as in breast feeding.
They should also be educated on the need for maintaining good oral
hygiene and the correct method of brushing.

Caries control
•Caries on the proximal
surfaces of teeth if not restored
in time can lead to loss of arch
length by movement of
adjacent teeth into that space.
•Should be detected by clinical
and radiographic examination
eg: bitewing radiographs are
used to detect proximal caries.
•Proper restoration of affected
teeth should be done
immediately to prevent loss of
arch length.

Care of deciduous dentition
•Prevention and timely restoration of carious teeth.
•Deciduous teeth are excellent natural space maintainers until
developing permanent teeth are ready to erupt in the oral cavity.
•To prevent early loss of deciduous teeth.
•Simple preventive procedures such as application of topical fluoride
and pit and fissure sealants help in preventing caries.

Extraction of supernumerary teeth
•Presence of supernumerary teeth and supplemental teeth can
interfere with eruption of nearby normal teeth.
•They can deflect adjacent teeth to erupt in abnormal positions.
•Such teeth should be identified and extracted before they cause
displacement of other teeth.
•Presence of an unerupted mesiodens prevents the two maxillary
central incisors from approximating each other.

•Most common location is seen in the anterior maxilla.
•The teeth are often discovered on the panoramic or occlusal radiograph
when a child is about 6 to 7 years of age, either during a routine dental
check up or when the permanent incisors fail to erupt.
•Simple cases are those when single supernumerary tooth exists and is
superficially located.
•Complicated cases involve multiple supernumerary teeth which may be
inverted.
•Superficially located supernumerary teeth can be removed by
uncomplicated extractions without disturbing the normal teeth.

•More supernumeraries present it is highly likely to have disturbed the
position and eruption timing of the normal teeth before their discovery
and the tubercle teeth are unlikely to erupt.
•Extractions should be carried out as soon as the supernumerary tooth
can be removed without causing any harm to developing normal teeth.
•If the treatment is delayed it is highly likely that the remaining normal
teeth will require surgical exposure or orthodontic traction.

Eliminating occlusal interference
•All functional prematurities should be eliminated as they can lead to
deviations in the mandibular path of closure and also predispose to
bruxism.
•Using articulating paper to detect the premature contact area can
eliminate these and then selective grinding is carried out.
•Also enamel pearls can cause premature contact and should be
eliminated by grinding.

Maintenance of tooth shedding time table
•A gap of not more than three months should exist in the shedding of
deciduous teeth and the eruption of permanent teeth in one quandrant
•Delay in eruption can be due to the following conditions
Presence of over retained deciduous teeth or roots
Supernumerary tooth
Cysts
Overhanging restorations in deciduous teeth
Fibrosis of gingival tissue
Ankylosed primary teeth

•A permanent tooth should replace its primary predecessor when approx three
fourths of the root of the permanent tooth has formed whether or not resorption
of the primary roots is to the point of spontaneous exfoliation.
•If the permanent tooth is noticeable and the primary tooth is mobile to such an
extent that it moves 1mm in the facial and lingual direction then the child is
encouraged to wiggle it out. If that cannot be accomplished then conventional
extractions should be prescribed.
•Most over retained primary maxillary molar teeth have either the buccal
roots or the large lingual root intact.
•By contrast most primary mandibular molars have either the mesial or distal
root still intact.

•Over retained teeth lead to gingival inflammation and hyperplasia that
cause pain and bleeding and sets the stage for deflected eruption paths that
can result in irregularity and cross bite. Once the primary tooth is out if
space is inadequate moderately abnormal facial or lingual positioning will
usually be corrected by equilibrium forces of the cheeks, lip and the
tongue.
•Generally incisors will erupt lingually and then move facially when the
primary tooth exfoliates.
•This emergence position is due to the lingual position of the developing
tooth bud.

•In the canine and pre molar areas the permanent tooth can emerge either
facially or lingually and will tend to move toward the correct position.
•If correction has not occurred when over bite is achieved however futher
alignment is unlikely in either the anterior or posterior quandrants and a
crossbite will result.

Management of ankylosed teeth
•Ankylosis is a condition characterized by absence of the periodontal
membrane in a small or the whole of the root surface.
•Ankylosed deciduous teeth do not get resorbed and therefore either
prevent the deciduous teeth from erupting or deflect them to erupt in
abnormal location.
•Appropriate management of an ankylosed primary tooth consists of
maintaining it until an interference with the eruption or drift of other teeth
begins to occur then extracting it and placing a space maintainer or other
space management appliance if needed. Should be diagnosed and surgically
removed at an appropriate time to permit the permanent teeth to erupt.

•If occlusal discrepancies have occurred from supra eruption of a tooth or teeth
in the opposing arch the use of partial dentures may be needed after extensive
occlusal adjustments.
•If tipping over the ankylosed tooth is recognised early placing a stainless steel
crown can prevent it. This is a temporary treatment.
•When significant vertical growth has occurred the ankylosed tooth will
again be out of occlusion then the primary ankylosed tooth should be
extracted surgically and then the permament teeth repositioned to regain
space.

•Any vertical discrepancies will be eradicated when the succedaneous tooth
brings bone with it during eruption.
•The situation is completely different when there is no succedaneous
erupting permanent tooth then the ankylosed tooth should be extracted early
to prevent any periodontal problems and before a large vertical discrepancy
occurs.
•Because erupting teeth bring alveolar bone with them in planning and
executing treatment it is best to move teeth into the edentulous space so that
the bone can be maintained and any potential periodontal defects can be
eliminated.
•Space maintenance can therefore be contraindicated rather than space
closure if replacement of missing tooth is a long-term plan

Management of abnormal frenal attachments
•Presence of thick and fleshy maxillary labial frenum that is attached
relatively low prevents the maxillary central incisor from approximating
each other.
•Abnormal frenal attachments in most patients are caused due to
hereditary factors.
•Should be diagnosed and treated at an early age.
•Presence of ankyloglossia or tongue-tie prevents normal functional
development due to lowered position of tongue and abnormalities in
speech and swallowing.
•They should be surgically treated to prevent full-fledged malocclusions.

Oral habits check up and educating parents and patients
•Finger and thumb sucking, nail biting, tongue thrusting and lip biting
should be identified and stopped.
•Digit sucking and pacifier sucking are most common.
•The effect of such habits on the hard and soft tissues depends on the
duration, intensity and frequency of the habit.
•Although it is possible to deform the alveolus and dentition during the
primary dentition years with an intense habit much of the change is
related to the anterior teeth.

•Maxillary incisors are tipped facially, mandibular incisors are tipped
lingually and some incisors are prevented from erupting.
•The overjet increases and the over bite decreases.
•In some cases maxillary intercanine and inter molar width may be
narrowed resulting in posterior cross bite.
•Girls are more likely to continue the habit than the boys.
•There is prevalence of increased posterior cross bites with pacifier usage.
•Pacifiers with a more physiological sucking pattern have not been proven
to be beneficial when compared with other pacifiers or to finger sucking.

•As long as the habit stops before the eruption of the permanent teeth most
of the changes resolve spontaneously.
•If the child does not want to stop the habit the dentist should follow the
“ adult approach” and (restrain any parental intervention). He should have a
straightforward discussion with the child, which should express concern
and include explanations from the dentist.
•Most children loose the habit by the age of 4 or 5 years at the latest.

•If a child needs help to stop the habit “ reminder therapy” is used
wherein adhesive bandage with waterproof tape on the finger that is
sucked can be used.
•Also the anterior portion of the quad helix can be quite a useful
reminder.
•If reminder system fails a reward system can be implemented.
•If all fails then an elastic bandage loosely wrapped around the elbow
prevents the arm from being flexed and the fingers from being sucked.
•Cemented reminder appliance can also be used.
•Prevention starts with proper nursing of the child and use of a
physiologically designed nursing nipple and pacifier will enhance normal
functional and deglutational activity.

Prevention of Milwaukee brace damage
•Milwaukee brace is an orthopaedic appliance used for correction of
scoliosis
•The appliance exerts tremendous amount of pressure on the mandible and
the developing occlusion leading to retardation of mandibular growth and
possible deformities
•Occlusion should be protected using functional appliances or positioners
made of soft materials

Deeply locked permanent molars
•Deciduous second molars occasionally have a prominent distal bulge
which prevents the eruption of the first permanent molars
•Slicing the distal surface of the second deciduous molars helps in guiding
the first permanent molars into occlusion

SPACE MAINTENANCE
Early loss of a primary tooth presents a potential alignment problem
because drift of permanent or other primary teeth is likely unless it is
prevented by space maintenance. Space maintenance is only possible when
adequate space is available and all unerupted teeth are present and at proper
stage of development. If there is not enough space or if succedaneous teeth
are missing space maintenance is alone inadequate.

Classification
Hitchcock
•Removable, fixed or semi fixed
•With bands or without bands
•Functional or non functional
•Active or passive
•Combinations of the above
Raymond C. Thurow
•Removable
•Complete arch
•Lingual arch
•extra oral anchorage
•Individual tooth

Hinrichsen
•Fixed space maintainers
Class I a) non functional types
-bar type
-loop type
b) functional types
-pontic type
-lingual arch type
Class II – cantilever type (distal shoe, band and loop)
•Removable space maintainers
Acrylic partial dentures

Requirements
•Maintain entire mesio-distal space created by lost tooth.
•Restore the function as far as possible.
•Prevent over eruption of opposing teeth.
•Should be simple in construction.
•Should be strong enough to withstand the functional forces.

•Should not exert excessive stress on adjoining teeth.
•Must permit maintenance of oral hygiene.
•Should not restrict normal growth and development and natural adjustments
which take place during the transition from deciduous to permanent dentition.
•Should not come in the way of other functions.

Factors governing the selection of appliance
•Patient co operation: with removable appliances greater co operation is
required.
•Appliance integrity: all types of appliance suffer breakage. But as per
Wright and Kennedy the mandibular removable appliance is the most
susceptible to breakage and that the integrity of fixed appliances is better.
•Maintenance: the length of time and projected maintenance should be
considered.

•Modifiability: anticipation of future modifications is essential.
•Limitations: loss of the first primary molar before eruption of the second
premolar while using band and loop.
•Cost: directly bonded are the best as time is saved. As lab time increases
labour charges increase.

Removable space maintainers
•They are space maintainers that can be removed and re inserted into the
oral cavity by the patient.
•Can be classified in functional and non functional.
•Functional space maintainers are those that incorporate teeth to aid in
mastication, speech and aesthetics.
•Non functional have an acrylic extension over the edentulous area to
prevent space closure.

Advantages
•Easy to clean and permit maintenance of oral hygiene.
•Maintain or restore vertical dimension.
•Can be worn part time and allows circulation of the blood to the soft tissues.
•Serve important functions like aesthetics mastication and phonetics.
•Dental check up for caries detection can be undertaken easily.

•Room can be made for permanent teeth to erupt without changing the
appliance.
•Stimulate eruption of permanent teeth.
•Band construction is not necessary.
•Help in preventing tongue thrust habit in the extraction spaces

Disadvantages
•May be lost or broken by patient.
•Un co-operative patients may not wear the appliance.
•Lateral jaw growth may be restricted if clasps are in corporated.
•May cause irritation to the underlying soft tissues.

•When aesthetics are of importance.
•If abutment teeth cannot support a fixed appliance.
•Cleft palate patients who require obturation of the palatal defect.
•If a radiograph detects that an unerupted tooth is not going to erupt in
less than five months time.
•When permanent teeth are not fully erupted it is difficult to adapt the
bands.
•Multiple loss of deciduous teeth which may require functional
replacement in the form of either partial or complete dentures.
Indications

Contraindications
•Lack of patient co operation.
•Patients who are allergic to acrylic materials.
•Epileptic patients who have uncontrolled seizures.

Acrylic partial dentures
•Useful in bilateral posterior space maintenance when more than one tooth
has been lost per segment and permanent incisors have not erupted as yet.
•They replace the occlusal function.
•Posterior space maintenance in conjunction with replacement of anterior
teeth for esthetics.
•Excellent retention is obtained by placement of several clasps which
brings about patient compliance.
•Acrylic portion can be adjusted such as to allow eruption of permanent
teeth.
•Problems encountered with these appliances is the failure to wear them
thus leading to loss of space or failure to remove it for cleaning can lead
to soft tissue irritation.

Full or complete dentures
•Useful when all the primary teeth are lost due to rampant caries and
cannot be restores.
•Was prevalent in the pre fluoridation era but is also seen now.
•Dentures not only restore masticatory function and esthetics but also
guide the first permanent molar into occlusion. This is done by
approximating the posterior border to the mesial surface of the unerupted
first molar.
•Can be subsequently adjusted to allow eruption of permanent molars and
incisors.

•Immediate acrylic partial denture with an acrylic distal shoe extension
has been used successfully to guide the first permanent molar into position
when the deciduous second molar is lost shortly before the eruption of the
permanent first molar.
•Tooth to be extracted is cut away from the stone model and a depression
is cut into the stone model to allow fabrication of the acrylic extension.
Removable distal shoe space maintainer
•The acrylic will extend into the alveolus after the removal of the primary
tooth and should extend one mm below the mesial marginal ridge at and
before its emergence from the bone.

•Should not be given in children who are immunocompromised or who are
at a risk for subacute bacterial endocardititis because complete
epithelialization around the intra alveolar portion has not been
demonstrated.

Fixed Space Maintainers
Advantages

•Bands and crowns are used which require minimum or no tooth
preparation.
•They do not interfere with passive eruption of abutment teeth.
•Jaw growth is not hampered.
•Succedaneous permanent teeth are free to erupt into the oral cavity.
•Can be used in un co operative patients.
•Masticatory function is restored if pontics are placed.


Disadvantages

•Elaborate instrumentation with expert skill is needed.
•Result in decalcification under the bands.
•Supra eruption of opposing teeth can take place if pontics are not used.
•If pontics are used it can interfere with vertical eruption of the abutment
tooth and may prevent eruption of replacing permanent teeth if the patient
fails to report.

Types
Band and loop space maintainer
•Unilateral fixed appliance indicated for space maintenance in the posterior
segment.
•The tooth distal to the extraction space is banded and a loop of thick stainless
steel wire is soldered to it with mesial end touching the teeth.
•Maintain the space of primary first molar before eruption of the permanent first
molar but it also can be used to maitain the space of either a primary first or
second molar after the first permanent molar has erupted.

•Simple cantilever design makes it ideal for unilateral isolated space
maintenance.
•Loop has limited strength therefore should not be expected to accept functional
forces of chewing.
•Should be restricted to build up the space for one tooth.
•Loop provides little if any functional replacement for the missing teeth and
will not prevent supraeruption of teeth in the opposing arch.

Crown and loop appliance
•Similar to band and loop in all respects except that a stainless steel crown
is used for the abutment tooth.
•The crown is used when in preference to a band when the abutment tooth
is highly carious exhibits marked hypoplasia or is pulpotomized.

Lingual arch space maintainer
•When multiple primary posterior teeth are missing and the permanent incisors
have erupted.
•Helps in maintaining arch perimeter by preventing both mesial drfting of the
molars and the lingual collapse of anterior teeth.
•A conventional lingual arch attached to bands on primary second or first
permanent molars and contacting the cingula of the maxilarry or mandibular
incisors, prevents anterior movement of the posterior teeth and posterior
movement of anterior teeth.

•Lingual arch should be positioned to rest on the cingula of the incisors
approximately 1 to 1.5 mm off the soft tissue and should be stepped to the lingual
in the canine region or remain away from the primary molars and unerupted
premolars.
•Common problems are distortion and breakage and loss.
•Maxillary lingual arches are contraindicated in patients whose bite depth causes
the lower incisors to contact the arch wire on the lingual of maxillary incisors.

•Similar to the lingual arch.
•Designed to prevent mesial migration of the maxillary molars.
•Constructed using 0.036 inch diameter hard stainless steel wire.
•Also call nance holding arch which is a maxillary lingual arch that does not
contact the anterior teeth but approximates the palate.
•Incorporates an acrylic button in the anterior region that contacts the palatal
tissue.
Palatal arch appliances

•Soft tissue irritation can be a problem.
•It can become embedded into the tissue if the tissue hypertrophies because of
poor oral hygiene or if appliance gets distorted.
•Can`be used when primary molars are lost bilaterally, then it is attached to
both the permanent first molars to prevent mesial tipping.

Transpalatal arch
•rrecommended for stabilizing the maxillary first premolar molars when
the primary molars require extraction.
•Cconsists of a thick stainless steel wire that spans the palate connecting
the first permanent molar of one side with the other.
•Bbest indication is when one side of the arch is intact and several primary
teeth on the other side are missing.

•The rigid attachment to the intact side usually provides adequate stability for
the space maintenance.
•Avoids contact with the soft tissue.
•The arch prevent the anterior movement of the molars by preventing rotation
of the tooth around the lingual root.

Distal shoe space maintainer

•Also known as intra alveolar appliance.
•Distal surface of the second primary molar guides the first molar into
position therefore when the second primary molar is removed prior to the
eruption of the first permanent molar the intra alveolar appliance provides
greater control of the path of eruption of the unerupted tooth and prevents
undesirable mesial migration.
•The appliance used in practice now is roches distal shoe or its
modifications using crown and band appliances with a distal intragingival
extension.

•Described by Stefan miller and Johnson in 1971.
•Method of construction is simple .
•Provides an esthetic component.
•Space maintainer consists of a plastic tooth fixed onto a lingual arch
which is in turn attached to molar bands.
Esthetic anterior space maintainer

Band and bar type space maintainer
•Fixed space maintainer.
•Abutment teeth on either side of the extraction space are banded and
connected to each other by a bar.
•Alternatively stainless steel crowns can be used and these are called
crown and bar space maintainers.

Has been defined as that phase of science and art of orthodontics
employed to recognize and eliminate potential irregularities and
malpositions of the developing dento facial complex.
Procedures undertaken:
1.Serial extraction
2.Correction of developing cross bite
3.Control of abnormal habits

4.Space regaining
5.Muscle excercises
6.Interception of skeletal malrelation
7.Removal of soft tissue or bony barrier to enable eruption of teeth

SERIAL EXTRACTION
•This approach called serial extraction was developed in Europe in the
1930’s and at times has been widely advocated as a simple way of dealing
with severe space problems.
•It is an interceptive procedure.
•Initiated in the early mixed dentition when one can recognize and
anticipate potential irregularities in the dento facial complex.
•Correction done by a procedure that includes the planned extraction of
certain deciduous teeth and later certain specific permanent teeth in an
orderly sequence and pre determined pattern.
•This is done to guide the erupting permanent teeth into a more favourable
position.

History
•Kjellgren (1929)
used the term serial extraction to describe a procedure where some
deciduous teeth followed by permanent teeth were extracted to
guide the rest of the teeth into normal occlusion.
•Nance (1940)
popularised the technique in the united states and termed it
`planned and progressive extraction’.
•Hotz (1970)
termed it `active supervision of teeth by extraction’.

Rationale
Based on two principles :
Arch length tooth material discrepancy
Whenever tooth material in considered more than arch length, tooth
material can be reduced and this is done by selective extraction of teeth so
that the rest of the teeth can be guided into correct occlusion.
Physiologic tooth movement
Human teeth have a natural physiologic tendency to move into
extraction spaces, thus by selective extraction of certain teeth the adjacent
teeth which are in the process of eruption are guided by natural forces into
extraction spaces

Indications
Class I malocclusion showing harmony between skeletal and muscular
system.
Arch length deficiency as compared to the tooth material is the most
important indication for serial extraction.
Arch length deficiency is seen in one of the following features:
· Absence of physiologic spacing
· Unilateral or bilateral premature loss of deciduous canines with mid
line shift
· Malpostioned or impacted lateral incisors that erupt palatally out of the
arch
· Markedly irregular or crowded upper and lower anteriors

· Localized ginigival recession in the lower anterior region is a characteristic
feature of arch length deficiency
· Ectopic eruption of teeth
· Mesial migration of the buccal segment
· Abnormal eruption pattern and sequence
· Lower anterior flaring
· Ankylosis of one or more teeth
· Where growth is not enough to overcome the discrepancy between tooth
material and basal bone patients with straight profile and pleasing appearance

Contraindications
•Class II and class III malocclusion with skeletal abnormalities
•Spaced dentition
•Anodontia and oligodontia
•Open bite/ deep bite

•Midline diastema
•Class I malocclsions with minimal space deficiency
•Unerupted malformed teeth
•Extensive caries or heavily restored permanent molars
· Mild disproportion between arch length and tooth material that can be
treated by proximal stripping

Advantages
•Treatment is more physiological.
•Psychological trauma associated with malocclusion can be avoided by
treatment of malocclusion at an early age.
∀Εliminates or reduces the duration of multibanded fixed treatment.
∀Βetter oral hygiene.
∀Ηealth of investing tissues is preserved.
•Lesser retention period.
• More stable results are achieved as the tooth amterial and arch length are
in harmony

•Serial extraction requires clinical judgment.
•Treatment time is prolonged ( carried out in stages over 2-3 years).
•It requires more frequent visits by the patient to the dentist.
•Patient has a tendency to develop tongue thrust in the open extraction
spaces.
Disadvantages

•Extraction of the buccal segment can lead to deepening of the bite.
•Risk of arch length reducing by mesial migration of the buccal segment leads
to poorly done serial extraction programme.
•Ditching or space can exist between the canine and second premolar.
•The axial inclination of teeth at the termination of the serial extraction
procedure may require correction.

Diagnosis
•Should involve comprehensive assessment of the dental skeletal and
soft tissue.
•Tooth material arch length discrepancy must ideally exist ( 5-7mm).
•Study model analysis should be carried out.
•Carrey’s analysis on the lower and arch perimeter analysis on the upper
should be carried out.

•Mixed dentition analysis should be carried out to determine space
required for erupting buccal teeth.
•Eruption status of teeth should be determined using opgs.
•The skeletal tissue assessment should involve comprehensive
cephalometric examination to study the underlying skeletal relation.

Procedure
The classic procedure consisits of four steps
1) Extraction of primary lateral incisors as the permanent central incisors
erupt.
2) Extractions of primary canines as the permanent laterals erupt.
3) Extraction of primary first molars usually 6 to 12 months before their
normal exfoliation, at the point when the underlying premolars have one
half to two thirds of their roots formed.
4) Extraction of the permanent first premolars before eruption of the
permanent canines.

Because the average first premolar is 7 to 8 mm wide, premolar
extraction creates 14 to 16 mm of space in the arch. Only the extremely
severe crowding of 10mm or more is there a chance of a reasonably
satisfactory result from serial extraction alone. After the serial extraction the
incisors tend to drift lingually and the posterior teeth tend to drift lingually
and posterior teeth tend to drift mesially to some extent, typically leading to
2 to 3 mm of space closure in each quadrant or 4 to 6 mm total. The
remainder of the space approximately 10 mm is available for resolution of
the crowding. Residual spaces will remain at the extraction sites if the
original discrepancy was much smaller than that.

Serial extraction in a patient with a relatively small discrepancy may
simplify later treatment even though closing residual spaces with
fixed appliances certainly will be required. If the space discrepancy is
large enough and if everything can be timed perfectly serial extraction
can produce total space closure and reasonably good alignment of the
teeth without orthodontic treatment. However such a favourable
outcome is rare and cannot be relied on. Even with vast majority of
patients undergoing serial extraction require a period of fixed
appliance treatment to achieve good alignment interdigitation and root
paralleling.

3 step extraction procedure
- deciduous canines are extracted to create space for alignment of
the incisors (8-9yrs)
- year later the deciduous molars are extracted so that the eruption
of first premolars is accelerated
- followed by the extraction of the erupting first premolars to permit
the permanent canines to erupt in their place
Dewel’s method

(Modified Dewel’s technique)
First premolars are enucleated at the same time of extraction of the
first deciduous molars. This is frequently necessary in the mandibular arch
where canines often erupt before the first premolars

Tweed’s method
- extraction of the first deciduous molars around 8yrs of age
- followed by extraction of the first premolars and the deciduous canines

Nance method
- involves extraction of deciduous first molars
- followed by the extraction of first premolars and the deciduous
canines

DEVELOPING ANTERIOR CROSS BITE
Condition characterized by reverse overjet where in one or more
maxillary anterior teeth is in lingual relation to the mandibular teeth.
Should be intercepted and treated at an early stage so as to prevent a
minor orthodontic problem progressing into a major dento facial anomaly.
Should be treated early because :
• Self perpetuating ie; if the condition is
• seen in the deciduous teeth in will be
• seen in the permanent teeth as well.
•
• Simple cross bites if not treated early have a potential of growing into a
• skeletal malocclusion that later need complicated orthodontic treatment
• combined at times with surgical procedures

In planning treatment for anterior crossbites, it is critically
important to differentiate skeletal problems of deficient maxillary or
excessive mandibular growth from crossbites due to only displacement of
teeth. The most common etiological factor of non skeletal anterior cross
bites is lack of space for the permanent incisors, and it is important that the
treatment plan focus on the management of the total space situation in
addition to the crossbite. Since the permanent tooth buds form lingual to the
primary teeth, a shortage of space may force the permanent maxillary
incisor teeth to remain lingual to the line of the arch and erupt into a
crossbite. If developing crossbite is discovered before eruption is complete
and overbite has not established, the adjacent primary teeth can be extracted
to provide the necessary space.

Primary teeth should be extracted bilaterally to prevent the midline from
migrating to the side of a unilateral to prevent the midline from migrating to
the side of unilateral extraction where extra room is available.
Dental anterior cross bites diagnosed after the incisors have erupted and
overbite is established require appliance therapy for correction. The first
concern is adequate space for tooth movement, which can be done by
bilateral disking, extraction of adjacent primary teeth or opening the space
for tooth movement. In a young child the best way to tip maxillary and
mandibular teeth out of cross bite is a removable appliance using finger
springs for the facial movement of maxillary incisors or an active labial bow
for lingual movement of mandibular incisors.

Can be classified into:
Dento alveolar cross bites
- One or more maxillary anterior teeth are in lingual relation to the
mandibular anteriors
- Often manifested as a single tooth cross bite
- Occurs sue to over retained deciduous teeth that deflect path of erupting
permanent teeth into a palatal position
- Effectively treated with tongue blades, Catlans appliance and double
cantilever springs with posterior bite plane

Skeletal anterior cross bites
Functional anterior cross bites
-Is the so called psuedo class III
-The mandible is compelled to close in a position forward of its true centric
relation
-Occur as a result of occlusal prematurities that cause a deflection of the
mandible into the forward postion during closure
- Treated by eliminating the occlusal prematurities

POSTERIOR CROSSBITES
The apparently unilateral posterior crossbite seen frequently in young
children, which is usually due to a mild bilateral constriction of the maxillary
arch, that creates occlusal interferences and a mandibular shift on closure is
not a severe problem.
When true unilateral posterior crossbites exist three relatively simple
methods can be applied:
Unequal w arches or quad helices
Lower arches stabilized with lingual arches to support cross elastics to the
maxillary teeth
Removable appliance that has been sectioned asymmetrically.

Final alternative is a lingual arch activated as a one couple device, so that
bodily movement on the anchorage side is pitted against facial tipping on the
movement side.

INTERCEPTION OF HABITS
Defined as those certain actions involving the teeth and the other
oral or perioral structures which are repeated often enough by some
patients to have a profound and deletrious effect on the positions of
teeth and occlusion.
Interceptive procedures should involve identification and removal
of the cause.

SPACE REGAINING
Space regaining procedures are undertaken at an early age to compensate
for the loss of space created by the loss of the primary molar and mesial
migration of the first permanent molar. This is bought about by the distal
movement of the first molar.
This is preferably done before the eruption of the second molar. Some
appliances used are :

GERBER SPACE REGAINER
A seamless orthodontic band or a crown is selected for the tooth to be
distalized. This space reginier consists of a U shaped hollow tubing and a U
shaped rod that enters the tubing. The rod is soldered or welded on the
mesial aspect of the first molar to be moved distally. The U shaped wire or
rod is fitted into the tube in such a way that the base of the U rod contacts
the tooth mesial to the edentulous area. Open coil springs of adequate length
are placed around the free ends of the U shaped rod and inserted into the
tubing assembly. The forces generated by the compressed open coil springs
bring about a distal movement of the first molar.

SPACE REGAINING USING JACK SCREWS
Use of jack screws placed in such a way that an increase in arch length
is obtained by distalization of the molar. The appliance consists of a split
acrylic plate with a jack screw in relation to the edentulous space and is
retained using adams clasp.

SPACE REGAINING USING CANTILEVER SPRING
Using simple finger springs the molar can be distalized to regain space
by using removable appliances.

MUSCLE EXCERCISES
These help in improving aberrant muscle function.
Exercise for the masseter muscle
This involves clenching the teeth and asking the patient to
count till ten. The patient is asked to repeat this exercise for
some duration of time.

Exercise for the lips (circum-oral muscles)
a)Stretching the upper lip to maintain lip seal is an important therapeutic
measure in patients having short hypo tonic lips. To aid in stretching the patient
is asked to hold a piece of paper between the lips.
b)Patients are asked to stretch the lip in a downward direction to the chin
c)Holding and pumping of water back and forth behind the lips
d)Massaging the lips
e)Button pull exercise: a button of one and a half inch diameter is taken and a
thread passed through the button hole. The patient is asked to place the button
behind the lip and pull the thread while restricting it from being pulled out by
the lip pressure
f)Tug of war exercise: using two buttons

Excercises for the tongue
a) One elastic swallow :
This is done to correct improper positioning of the tongue.
A 5/16 inch intra oral elastic is placed on the tip of the tongue and
the patient is asked to raise the tongue and hold the entire the elastic
against the rugae area and swallow.
b) Tongue hold exercise:
A 5/16 inch elastic is positioned over the tongue in a designated
spot for a prescribed period of time with the lips closed. The patient is
then asked to swallow with elastic in place and lips apart.

c) Two elastic swallow
Two 5/16 inch elasctics are placed over the tongue one in the
midline and the other on the tip and the patient is asked to swallow with
elastics in position.
d) The hold pull exercise
The tip of the tongue and the mid point are made to contact the
palate and the mandible is gradually opened. This exercise helps in
stretching the lingual frenum.

INTERCEPTION OF SKELETAL MALRELATIONS
Skeletal malocclusions if detected at an early age can be corrected using
growth modulation procedures.
Interception of class II malocclusion
Class II occurs as a result of excessive maxillary growth, deficiency in
mandibular growth or a combination of both.
Maxillary growth can be restricted by use of a face bow with head gear.
Class II with mandibular deficiencies are treated with use of myofunctional
appliances

Interception of class III malocclusions
Class III is a result of mandibular prognathism, maxillary retrognathism or a
combination of both.
Chin cap with head gear helps in restriction of mandibular growth.
FR III or face mask therapy is used in cases of maxillary deficiency.

REMOVAL OF SOFT TISSUE AND BONY BARRIERS
Whenever a permanent tooth fails to erupt at the appropriate time its
eruption may be stimulated by surgically exposing the crown.
The surgical procedure involves excision of the soft tissue and
removal of any bone overlying the crown of the unerupted tooth. The
extent of the tissue removal should be such that the greatest diameter of
the crown of the tooth is exposed. The surgically created opening in the
tissue is slightly larger than the greatest dimension of the tooth. The
surgical wound is given a dressing for a period of 2 weeks,

Preventive

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