Serial Extraction

Question 1

What is serial extraction?

Answer 1

A clinical procedure that involves the timed sequence of extractions of certain primary, and permanent teeth in mixed dentition.

Question 2

What is the “aim” of serial extraction?

Answer 2

The goal is to influence the permanent first premolars to erupt ahead of the canines so that they can be extracted and the canines can move distally into this space

Question 3

Why do we do serial extractions?

Answer 3

• In many children with severe crowding, when expansion is not enough to relieve severe crowding.
• A planned sequence of tooth removal can reduce crowding and irregularity during the transition from the primary to the permanent dentition.
• It will also allow the teeth to erupt over the alveolus and through keratinized tissue, rather than being displaced buccally or lingually.

Question 4

Other names used for serial extraction

Answer 4

“Guidance of occlusion”
“Guidance of eruption”
- Simply involves the timed extraction of primary and, ultimately, permanent teeth to relieve severe crowding.

Question 5

When is serial extraction best used?

Answer 5

• No skeletal problem exists.
• Space discrepancy is >10 mm per arch.

Question 6

Although serial extraction makes later comprehensive treatment easier and often quicker, by itself it almost _____ results in ideal tooth position or closure of excess space.

Answer 6

Never

Question 7

It is unwise for a non-specialist to start serial extraction in a child who has a skeletal problem because the closure of extraction spaces would be affected by how the skeletal problem was being addressed

Question 8

When does serial extraction begin?

Answer 8

begins in the early mixed dentition with extraction of primary incisors if necessary, followed by extraction of the primary canines to allow eruption and alignment of the permanent incisors.

Question 9

Side-effects of serial extraction?

Answer 9

As the permanent teeth align without any appliances in place, there is usually some lingual tipping of the lower incisors, and overbite often increases during this stage.

Question 10

Upper arch considerations when talking about serial extractions

Answer 10

The maxillary premolars usually erupt before the canines, so the eruption sequence is rarely a problem in the upper arch.

Question 11

Lower arch considerations when talking about serial extractions

Answer 11

The canines often erupt before the first premolars, which causes the canines to be displaced facially.

Question 12

How to avoid this result?

Answer 12

The lower primary first molar should be extracted when there is one-half to two-thirds (1/2 – 2/3) root formation of the first premolar developed.
Speeding up the PM eruption and cause it to enter the arch before the canine allowing for easy access for TE of first PM before canine erupts

Question 13

Complication (Lower primary first molar)

Answer 13

A complication can occur if the primary first molar is extracted early and the first premolar still does not erupt before the canine. Leading to impaction of PM that requires surgical removal later on

Question 14

Complications (canine eruption)

Answer 14

at the time of the primary first molar extraction, it may be obvious that the canine will erupt before the premolar.
Causing the underlying premolar can also be extracted at the same time of the primary first molar extraction.
* a procedure termed enucleation.
If possible, however, enucleation should be avoided because the erupting premolar brings alveolar bone with it.

Question 15

What is enucleation?

Answer 15

A procedure where the underlying premolar can also be extracted at the same time of the primary first molar extraction.

Question 16

What can enucleation cause?

Answer 16

Early enucleation can leave a bone defect.

Question 17

Complication (increased overbite)

Answer 17

A variation in the extraction sequence can be used to help in controlling this
problem.
* The mandibular primary canines are retained.
* Instead, the primary first molars will be extracted.
* With this approach, eruption of the permanent first premolars is encouraged, and the incisors are less prone to tip lingually.

Question 18

What are the Advantages of Mechanotherapy after S.E?

Answer 18

• Proper space closure
• Ideal teeth alignment
• Ideal root parallelism
• Ideal over-bite

Question 19

The premolar extraction spaces close partially by mesial drift of the second premolars and permanent first molars but largely by _____ _______ __ ____ ________

Answer 19

distal eruption of the canines.

Question 20

In many patients with severe crowding, the primary canines are lost due to ectopic eruption of the _____ and cannot be maintained.

Answer 20

laterals

Question 21

Review clinical steps

Question 22

Step 1

Answer 22

Step 1:
* The primary canines are extracted to provide space for alignment of the incisors.

Question 23

Step 2

Answer 23

Step 2:
* The primary first molars are extracted when one-half to two-thirds of the first
premolar root is formed, to speed eruption of the first premolars.

Question 24

Step 3

Answer 24

Step 3:
* When the first premolars have erupted they are extracted and the canines erupt into the remaining extraction space.

Question 25

Step 4

Answer 25

Step 4:
* The residual space is closed by drifting and tipping of the posterior teeth unless full appliance therapy is implemented.