To extract or not to extract??

04/11/23 copyright (your organization) 2003 2

Extraction in orthodontics is carried out in cases where there is space deficiency to align teeth.

Extraction is considered in the optimal treatment plan only after

1.Clinical examination 2.Model analysis 3.Cephalometric analysis

Deficiency in space due to: 1.Malrelation between arches 2.Disproportion between arch/tooth size – crowding. 3.Preservation of arch symmetry

1.Wilkinson’s MethodWilkinson extractions 2.Balancing extractions 3.Therapeutic extractions 4.Enforced extractions 5.Serial extractions

Advocated extraction of

Felt that they are susceptible to caries and extraction of these teeth will provide additional space for third molars and also relieve crowding.

Disadvantage: 1.loss of adequate anchorage during

treatment. 2.Excessive drifting of

3.Mesial drifting of lower 2nd molars, is not bodily movement but tilting/rotation

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Also called as compensation extractions If a tooth is absent in one quadrant the

opposing tooth may supraerupt causing malocclusion.

To prevent such malocclusions in the same arch on opposite sides or in the opposing quadrant of the other arch extractions are carried out.

These extractions are performed as the situations warrants/or it becomes imperative/compulsion.

These include: - Grossly decayed teeth - Poor periodontal condition -Fractured teeth - Impacted teeth Tooth in the line of fracture

Extractions carried out for the purpose of treatment.

Prior to extraction of teeth for treatment various factors such as

1.Condition of the teeth(caries) 2.Amount of space required 3.Skeletal/dental discrepancy 4.Age and dental development of the

patient.etc are important.

Is an interceptive procedure where in a few deciduous and permanent teeth are extracted to facilitate the alignment of the remaining permanent teeth.

Upper incisors: 1.Unfavorable impaction 2.Dilaceration 3.Gross caries 4.Fracture/injury 5.Structural defects 6.Conical lateral incisors with invaginated

crowns - prone to caries.

- Form the pillars of treatment and are most rarely extracted.

- Unfavourable impaction. - All teeth are well aligned and only canine

is totally ectopically erupted.(labial/lingual)

1.Ectopic eruption 2.Class-3 cases reverse overjet 3.Severe gingival recession/bone loss

Most preferred because: 1.Space required is more than 5 mm. 2.Extraction site is close to the problem. 3.Anchorage is maximum as 5 & 6 are present. 4.Midway between anterior and posterior

teeth. 5.If ectopically erupted 6.Mechanics are easier to perform during treatment. 7.Severely rotated 8.Gross caries

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CONTRA INDICATIONS

Minimal crowding

Minimal retraction

Average/good profile

1.Space required is less than 5mm. 2.Ectopic eruption 3.Severely rotated tooth 4.Gross caries

* * * * Important: Though the mesio-distal diameter of First

and second premolar are almost the same we can move the anterior teeth more in case of 1st premolar extraction because 5 & 6 are present for anchorage where as extraction of 2nd premolars causes more anchor loss as only 1st molars are present.

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- These are generally not extracted. - Wilkinson extraction - Grossly decayed - Open bite and high angle cases - Minimal space requirement of about 2 mm - But not always done.

1.Allows proper alignment of 3rd molars 2.Distilization of 1st molars 3.Open bite cases - however they are not routinely extracted. Third molars: - Impaction - Thought to cause crowding in the

anterior region as they erupt,but has been proven wrong.

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EXTRACTION SITE FAR-CROWDING

ADDITIONAL Rx TIME

DELETERIOUS

EFFECTS

POSSIBLE IMPACTION3RD MOLARS

EXCESS REMOVALTOOTH SUBSTANCE

1. Extraction 2.Expansion - skeletal - dental 3. Interproximal stripping 4. Derotation 5. Distalisation