it explain need for extraction, choice of teeth for extraction, Wilkinson extraction, extraction of permanent teeth without appliance therapy, balance extractions, compensating extractions, additional factor to consider in extraction of teeth.

1. Extractions in Orthodontics
Dr. Shweta A. Kolhe
BDS.MDS (Orthodontist). PhD Scholar.

2. • The philosophy of extraction in conjunction with orthodontic
treatment is not new.
• Extractions in orthodontics requires the reduction of one or more
teeth include
serial extraction- carried out as an interceptive procedure during the
mixed dentition period.
Therapeutic extraction- treatment procedure for gaining space.

3. Extraction and controversy in orthodontics
• Edward Angle- belied that an individual was capable of having 32
teeth in normal occlusion and orthodontic treatment for every
patient involved expansion of arches.
• Calvin Case- argued that arches could always be expanded so that
teeth could be placed in alignment, neither aesthetics nor stability
would be satisfactory in the long term for many patients. thus
advoated extraction of teeth.

4. • Charles Tweed- observed that the post-treatment occlusion was
more stable in patients treated with extraction of four first premolar.
• Begg- in Australia, argued that premolar extractions were required in
order to compensate for the lack of interproximal wear seen in the
modern dentition, through lack of a coarse diet.
It is advisable that each case must be assessed on its merits with
more sensible approach based on the requirements of the individual
case rather than the two extremes seen in the past century.

5. Need for extraction
• Arch length-tooth material discrepancy-
- The presence of tooth material in excess of the arch length can result
in crowding of teeth or proclination of anteriors.
- In many cases the tooth material-arch length disproportion cannot be
treated by increasing the arch length.
- Hence reduction of tooth material is the only alternative.

6. Mesial migration of
buccal segment can
result in reduction
of arch length to
accommodate all
the teeth.
Markedly
irregular or
crowded
upper an
lower
anteriors.
Lower anterior
faring is an
indication of
arch length
deficiency
Unilateral or
bilateral
premature loss
of deciduous
canines with
midline shift.
Sign of arch length discrepancy

7. Sign of arch length discrepancy
Absence of
physiologic spacing
in the primary
dentition indicate
future arch length
deficiency.
Ectopic eruption
of teeth is often
a result of arch
length
deficiency.
Localized gingival
recession in the
lower anterior
region is a
characteristic
feature of arch
length deficiency.
Malpositioned or
impacted lateral
incisors that
erupt palatally
out of the arch.

8. • Correction of sagittal inter-arch relationship -
- Angle Class I :
characterized by a normal sagittal inter-arch relation. Thus it is not
advisable to discourage the development of one dental arch more than
the other. Hence in Angle’s Class I cases, it is preferable to extract in both
the arches.

9. - Ange Class II:
upper dental arch is forwardly placed or the lower arch placed back.
Thus by extracting only in the upper arch it is possible to reduce the
abnormal upper proclination and also to discourage the forward
development of the upper arch.
-where there is lower arch crowding or the molars are not in full Class II
occlusion, may be necessary to extract in both arches.

10. • Angle Class III:
Beneficial to avoid extraction in the upper arch as it may affect the
forward development of the maxilla.
Angle class III cases are preferably treated by extraction only in the
lower arch or by extraction in both arches.

11. • Abnormal size and form of teeth:
Anomalies includes macrodontia, severely hypoplastic teeth,
dilaceration and abnormal crown morphology.
• Skeletal jaw malrelations :
Sever skeletal malrelationship of the jaws ma not be satisfactorily
treated using orthodontic appliances alone. Surgical respective
procedures along with extraction maybe required.

12. The Choice of teeth for extraction
• The Choice of teeth for extraction depend on number factors
including:
1. Arch length tooth material discrepancy
2. The direction and amount of jaw growth
3. The facial profile
4. The state and position of teeth in particular
5. The entire dentition
6. Age of patient

13. Extraction of upper incisors
1. An unfavorably impacted upper incisor that cannot be brought to normal
alignment.
2. A buccally/ lingually blocked out lateral incisor with good contact between the
central incisor and canine can be extracted.
3. If one of the lateral incisors is congenitally missing, the opposite lateral may
have to be extracted in order to maintain arch symmetry.
4. A grossly carious incisor that cannot be restored may have to be sacrificed.
5. Malformations of incisor crowns that cannot be restored by prosthesis may
necessitate their extraction.
6. Trauma or irreparable damage to incisors by fracture may indicate their
removal.
7. An incisor with dilacerated root cannot be efficiently moved by orthodontic
therapy. It is hence preferable to extract them.

14. Extractions of Lower Incisors
1. If one of the incisors is completely out of the arch with good inter-
dental contact between the rest of the teeth.
2. A lower incisor that was traumatized, or exhibiting severe caries,
gingival recession or bone loss may have a poor prognosis.
3. Presence of severe arch length deficiency is often characterized by
the presence of fan-shaped flaring out of the lower incisor crowns.
In these cases it may not be possible to flatten the lower anterior
segment by extracting teeth further distally in the arch. Thus one of
the incisors may have to be extracted so as to improve the crowding
and axial inclination of rest of the incisors.

15. 4. In mild Class III cases with lower incisor crowding, one of the lower
incisors may be extracted to achieve normal overjet, overbite and
to relieve crowding.
5. Cases where a tooth size discrepancy exists, for example upper peg
shaped laterals or missing upper lateral incisors, it may be extracted
to achieve normal overjet, overbite and to relieve crowding.
6. Cases where a tooth size discrepancy exists, for example upper peg
shaped laterals or missing upper lateral incisors, it may be of benefit
to extract a lower incisor.
7. Treatment of Class I cases with moderate lower labial segment
crowding of up to 5 mm (i.e. the size of a lower incisor) may be
treatment with loss of a lower incisor.

16. • Extraction of one lower can be considered in adult who have had
previous loss of premolars in each quadrant and present with late
lower labial segment crowding.

17. Extractions of Canine
1. The canines develop far away from their final location. In addition
they a long path of eruption from their site of development to their
final position in the oral cavity. Thus the canines are highly
susceptible to ectopic eruption and impaction. Such unfavorably
impacted canines or canines that have erupted in unusual locations
may have to be removed.
2. A canine that is completely out of the arch with reasonably good
contact between the lateral incisor and first premolar is an
indication for its extraction.

18. 3. Premature shedding of a deciduous canine usually indicates the
extraction of its fellow on the opposite side of the arch to restore
symmetry.
4. In Class II cases if the lower deciduous canines are shed early, the
upper deciduous canines should also removed so as to avoid
worsening of the post- normalcy (Class II tendency).
5. In Class III cases if the upper deciduous canines are shed early, it may
necessitate the extraction of the lower deciduous canines to avoid
worsening of the pre-normalcy (Class III tendency).
6. Deciduous canines may be extracted as a part of serial extraction
procedure.

19. Extractions of First Premolars
• Reasons for extraction :
1. Their location in the arch is such that the space gained by their
extraction can be utilized for correction both in the anterior as wel
as the posterior region.
2. The contact that results between the canine and second premolar is
satisfactory.
3. The extraction of the first premolar leaves behind a posterior
segment that offers adequate anchorage for the retraction of the
six anterior teeth.

20. Indications for first premolar extraction:
1. The teeth of choice for extraction to relieve moderate to severe
anterior crowding of the upper or lower arch.
2. The first premolars are extracted for correction of moderate to
severe anterior proclination as in a Class II, division 1 malocclusion
or a Class I bidental protrusion.

21. Extraction of second premolars
1. To relieve mild crowding and proclination where anchorage loss is
desirable
2. Unfavorably impacted
3. In open bites, they are preferred over first premolars as deepening
of bite is encouraged.
4. If grossly decayed or has a large filling with questionable prognosis,
then they are questionable prognosis, then they are extracted
instead of first premolars.

22. Extractions of first permanent molars
• Reasons for avoiding extraction of first permanent molars:
1. Does not give adequate space in the incisor region.
2. Extraction of the first molar result in deepening of the bite.
3. The second premolar and molar may tip into the extraction
space.
4. Mastication may be affected.

23. Indications for first molar extraction
1. Minimal space requirement for correction of mid anterior crowding
or mild proclination.
2. Grossly decayed molar or heavily filled teeth.
3. Molars that are extruded or with marked periodontal involvement.
4. Open bite cases can benefit from extraction of first molar, as there
is a tendency for the bite to deepen after extraction of first molars.
5. Orthodontically retracted cases presenting with Angle Class II
malocclusion where the first premolars have already been
extracted.

24. Wilkinson extraction
• Wilkinson advocated extraction of all the four first permanent molars
between the ages of 8 ½ - 9 ½ years.
• The basis for such extractions is the fact that the first permanent molars
are highly susceptible to caries.
• Benefits of extracting the first molars at an early age are:
A. Their extraction provides additional space for eruption of the third
molars. Thus impaction of third molars can be avoided.
B. Crowding of the arch is minimized.

25. • Wilkinson’s extraction has number of drawbacks:
A. The extraction of first molars offers limited space to relieve
crowding.
B. The second bicuspids and second molars rotate and may tip
into the extraction space.
C. The removal of the first molars deprives the orthodontist of
adequate anchorage for any orthodontic appliance.

26. Extractions of second permanent molars
1. To prevent third molar impaction
2. To relieve impaction of second premolar
3. Lower incisor crowding
4. To enable distalization of first molars
5. Open bite cases.

27. 1. To prevent third molar impaction
• Cases where third molars are upright or not tipped mesially more than
300. then upper second molar extraction if carried out prior to the
eruption of the third molars, results in satisfactory third molar position.
2. To relieve impaction of second premolar
•Premature loss of ‘E’ allow drift of first permanent molar leaving
inadequate space for second premolar such case extraction of second
molar allow distal movement of first permanent molars and offer sufficient
space for the second premolar to erupt.

28. 3. Lower incisor crowding
• very mid crowding in the anterior part of the arch can be relived by
extraction of second molars.
4. To enable distalization of first molars
• Rapid and efficient distalization of first permanent molar can occur.
5. Open bite cases
• Extraction of second molars deepens the bite.

29. Extractions of third molars
• Etraction of third molar does not yield space that can be used for
decrowding or reduction of proclination.
• Reasons are as follow:
A. Grossly impacted
B. Grossly malformed
C. Eruption of third molars cause late lower anterior crowding.

30. Extractions of permanent teeth with-out
appliance therapy
• Extraction of the lower first premolars are often associated
with spontaneous decrowding of the lower anteriors. Such
spontaneous decrowding by drifting of teeth, referred to as
driftodontics are less frequent in the upper arch.

31. Balance extraction
• Removal of a tooth from one side of a dental arch result in tendency for the rest
of the teeth to move towards the extraction space.
• Thus the midlines of the arch may shift to the side of the extraction space.
• To avoid such unaesthetic shifts of the dental arch, balancing extractions are
advocated.
• Balancing extraction refers to removal of another tooth on the opposite side of
the same arch.

32. Compensating Extractions
• Compensating extraction refers to extraction of teeth in
opposite jaws.
• Compensating extractions are carried out to preserve the
buccal occlusal relationship.
• In a class I relation it is usually advisable to extraction in both
the arches to preserve the buccal occlusal relationship.

33. Additional factors to consider in extraction of
teeth
1. Quality of the teeth
Hypoplastic, heavily restored or carious teeth should generally be
removed in preference to healthy teeth.
2. Abnormalities of tooth form
Teeth of abnormal form or size may be considered for removal
as they can look unsightly and be difficult to align.
3. Medical history
e.g. patient with cardiac problem may need antibiotic
prophylaxis prior to extraction of teeth. Extraction is potentially
traumatic experience.

34. Facial pattern and extractions
Dolichocephalic facial pattern
• Dolichofacial patients feature increased facial height
relative to the width, exhibiting a long and narrow face.
• They have hypotonic facial muscles in the vertical
direction and can have anterior overbite.
• They suffer from greater anchorage loss, which helps in
closing spaces.
• Greater control should be exercised, however, in order to
avoid excessive anchorage loss and the consequent lack
of space to ensure the planned correction.
• Extrusive mechanics should be avoided, as well as distal
tooth movement.

35. Brachycephalic facial pattern :
• Brachyfacial patients facial width is greater than their
facial height, displaying a broad, short an globular
face.
• These patients are not as prone to anchorage los due
to certain muscle characteristic (hypertonic
masticatory muscles) that hinder tooth movement.
• Many patients have deepbite. Since in these cases
tooth extractions tend to worsen the vertical overlap,
adequate mechanical control is required.