Serial Extraction Pedo

SERIAL SERIAL

EXTRACTIONEXTRACTION

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INTRODUCTION HISTORY RATIONALE INDICATIONS CONTRAINDICATIONS ADVANTAGES DISADVANTAGES DIAGNOSITC PROCEDURE PROBLEMS IN SERIAL EXTRACTION

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INTRODUCTION:

Serial Extraction is an interceptive orthodontic

procedure usually initiated in the early mixed

dentition.

It is a procedure that includes the planned

extraction of certain deciduous teeth & later specific

permenent teeth in an orderly sequence & pre-

determined pattern to guide the erupting permenent

teeth into a more favourable position. www.fourthmolar.com

HISTORY:-HISTORY:-

Kjellgren (1929) used the term “Serial extraction” to describe a procedure where some deciduous teeth followed by permenent teeth were extracted to guide the rest of the teeth into normal occlusion.

Nance during 1940’s popularized this technique in united states of AMERICA, termed it “planned & progressive extraction” & has been called the ‘father’ of Serial extraction philosophy in united states.

Hotz in 1970 called such a procedure “active

supervision” of teeth by extraction. www.fourthmolar.com

Serial extraction is based on 2 basic principles:- RATIONALE:-Arch Length tooth material discrepancy: Whenever there is an excess of tooth material as compared

to the arch length a selective extraction of some teeth is done so that rest of the teeth can be guided to normal occlusion.

Physiologic tooth movementPhysiologic tooth movement

Human dentition shows a physiologic tendency to move towards an extraction space.

Thus by selective removal of some teeth the rest of the teeth which are in the process of eruption are guided by the natural forces into the extraction spaces. www.fourthmolar.com

INDICATIONS FOR SERIAL EXTRACTION

1. Class I malocclusion showing harmony between skeletal & muscular system.

2. Arch length deficiency as compared to the tooth material is the most imp. indication for serial extraction.

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Absence of physiologic spacing

Unilateral or bilateral premature loss of deciduous canines with midline shift.

Malpositioned or impacted lateral incisors.

Irregular or crowded upper & lower incisors.

Localized gingival recession in the lower ant region

Ectopic eruption of teeth.

Mesial migration of buccal segment.

Arch length deficiency is indicated by the presence of 1 or more of the following features:-

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Abnormal eruption pattern & sequence.

Lower anterior flaring.

Ankylosis of 1 or more teeth.

3. Where growth is not enough to overcome the discrepancy between tooth material & basal bone.

4. Patients with straight profile & pleasing appearance.

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Contraindications of Serial ExtractionClass II & III malocclusion with skeletal abnormalities.

Space dentition.

Anodontia/ oligodontia.

Open bite & deep bite.

Midline diastema.

Class I malocclusion with minimal space deficiency.

Unerupted malformed teeth. Eg. Dilacerations.

Extensive caries or heavily filled I permenent molars.

Mild disproportion between arch length & tooth material.www.fourthmolar.com

Advantages of Serial Advantages of Serial Extraction:Extraction: Treatment is more physiologic as it involves guidance of

teeth into normal positions. Psychological trauma associated with malocclusion can be

avoided by treatment of the malocclusion at an early stage. It eliminates the duration of multi-banded fixed treatment. Better oral hygiene is possible thereby reducing the risk of

caries. Health of investing tissue is preserved. Lesser retention period is indicated at the completion of

treatment. More stable results are achieved as the tooth material &

arch length are in harmony. www.fourthmolar.com

Disadvantages of Serial Extraction:

It can not be universally applied to all patients. Treatment time is prolonged as the treatment is

carried out in stages spread over 2-3 years. It requires the patient to visit the dentist thus

patient co-operation is needed. As the extraction spaces are created that close

gradually the patient has a tendency of developing tongue thrust.

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Extraction of buccal teeth can result in deepening of the bite.

If the procedure are not carried out properly there is a risk of arch length reducing by mesial migration of the buccal segment.

Ditching or space can exist b/w the canine & 2nd premolar.

The axial inclination of teeth at the termination of the serial extraction procedure may require correction.

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ProcedureProcedure

There are mainly three methods:-

•Dewel’s Method

•Tweed’s Method

•Nance method.

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DEWEL’S METHODDEWEL’S METHOD Dewel has proposed a 3 step serial extraction

procedure. In the 1st Step, the deciduous canines are extracted

to create a space for alignment of the incisors.

This step is carried out at 8-9 years of age.

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After 1 years, the deciduous 1st molars are extracted so that the eruption of 1st premolars is accelerated.

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This is followed by the extraction of the erupting 1st premolar to permit the permanent canines to erupt in their place.

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In some cases, a Modified Dewel’s Technique is followed where in the 1st premolar are enucleated at the time of extraction of the 1st deciduous molars.

This is frequently necessary in the mandibular arch where the canines often erupt before the 1st PM

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TWEED’S METHOD:This method involves the extraction of the deciduous

1st molars around 8 years of age. This is followed by the extraction of the 1st premolar

& the deciduous canines.

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Nance Method:

This is similar to the Tweed’s technique & involves the extraction of the deciduous 1st molars followed by the extraction of the 1st Premolars & the deciduous canines.

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Problems in the serial Problems in the serial extractionextraction

Ant. crossbites can broadly classified as:-

• Dento- alveolar ant. crossbites.

• Skeletal ant. crossbites

• Functional ant. crossbites.

ANTERIOR CROSSBITES

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Dento alvealor ant. Crossbites:

Ant. crossbite in which 1 or more maxillary teeth are in lingual relation to the mandibular ant. is termed as “Dentoalveolar ant. Crossbites”.

This is manifested as single tooth crossbite & usually occurs due to over retained deciduous teeth.

Functional ant. Functional ant. Crossbites:Crossbites: Also called “Pseudo Class III Malocclusion”.

Occurs as a result of occlusal prematurities.

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Skeletal ant. Skeletal ant. crossbitecrossbite

These are usually a result of skeletal discrepencies in growth of maxilla or the mandible.

Ant. cross bite can be a result of maxillary retrognathism or hypoplasia or mandibular prognthism.

These are treated by use of myofunctional or orthopadic appliances.

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References :References :

Textbook of orthodontics : GRABER

Textbook of orthodontics : S.I. BHALAJHI

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