Presented in Journal club 28 11 2018 at KCD Peshawar Reference: Orthodontics Part 8: Extractions in orthodontics By H. Travess, D. Roberts-Harry and J. Sandy doi:10.1038/sj.bdj.4810979

1. EXTRACTIONS IN ORTHODONTICS
DR. JAWAD TARIQ PGR MCPS Family Dentistry
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2. LEARNING OBJECTIVES
 Explain the method used for teeth alignment
 Discuss and demonstrate each method with their final results
 List some important factors affecting the decision to extract
 Discuss the ease of extraction and the presence of impacted teeth with an example
 Discuss briefly about overbite correction
 Discuss briefly about the extraction of each tooth individually
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3. INTRODUCTION
 Extractions in orthodontics remains a relatively controversial area
 It is not possible to treat all malocclusions without extracting any teeth
 Extractions of specific teeth are required in the various presentations of
malocclusion
 In some situations careful timing of extractions may result in spontaneous correction
of the malocclusion
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5. ARCH ALIGNMENT FOR CROWDED TEETH
 Arch Expansion
 Reduction in Tooth Size
 Reduction in Tooth Number
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6. ARCH EXPANSION
• Arch expansion can be achieved by moving teeth buccally and labially
but the long-term stability and whether bone grows as teeth are moved
through cortical plates remain contentious issues
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Arch
expansion
Maxillary
Mandibular
• Suture in the maxilla can ‘split’ with rapid
maxillary expansion. The split suture fills in
with bone and thus a wider arch to
accommodate teeth is achieved
• More stable result than other methods
• Increasing mandibular length for teeth
accommodation relapses in nearly 90% of
cases

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Reduction in Tooth Size
• Particularly in the labial segments with interdental stripping, is
another mechanism to relieve crowding.
•Variable relapse has been reported and one study noted relapse of some degree in
all cases.

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Reduction in Tooth Number
• The reduction in tooth number in usually achieved by tooth extractions

10. CONSIDERATION BEFORE EXTRACTING TEETH
 It is important to consider the patient as a whole in the treatment planning.
 Medical history, attitude to treatment, oral hygiene, caries rate and the
quality of the teeth are important
 A dogmatic approach is inadvisable and each case must be assessed on its
merits
 The decision on whether or not to extract teeth is based on an assessment
of many factors including:
- Crowding
- Increase in overjet
- Change in arch width
- Curve of Spee
- Adjusting the torque of the anterior teeth
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11. FACTORS AFFECTING THE DECISION TO EXTRACT
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12. FACTORS AFFECTING THE DECISION TO EXTRACT
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13. EASE OF EXTRACTION AND PRESENCE OF IMPACTED TEETH
 The extraction of teeth is a potentially traumatic experience.
 The use of general anesthesia is usually considered in dealing with
unerupted teeth, first molars, multiple extractions in four quadrants and
specific phobias.
 If teeth are impacted or ectopically positioned, extraction of an erupted tooth
can guide the path of eruption of the impacted tooth
and obviate the need for minor oral surgery.
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14. EXAMPLE
 Impaction of lower second premolars are
relieved by the removal of the lower right
first premolar and lower left first molar,
which only required local analgesia and is
less traumatic than the removal of the
impacted tooth.
 After that, spontaneous alignment
occurred with both impacted premolars
erupting successfully into the occlusion
with no active treatment
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15. OVERBITE IN ORTHODONTICS
 Space closure with fixed appliances tends to increase the overbite.
 In some malocclusions, where the anterior face height is reduced, extractions
can make space closure difficult.
 It is important to recognize whether a case is genuinely crowded or whether the
teeth are displaced lingually. Lingually displaced lower labial segments are
frequently not crowded, even though they may appear to be so
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16. CORRECTION OF OVERBITE
 Proclination of the lower labial segment reduces the overbite, as well as
overjet, and may obviate the need for extractions.
 Exaggerated curve of Spee is frequently observed in dental malocclusions
with deep overbites.
 So, flattening of an accentuated curve of Spee in order to reduce an overbite
is an option, where proclination is contraindicated
 It does require space, for which the extraction of lower teeth can sometimes
be considered.
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18. EXTRACTION OF SPECIFIC TEETH
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19. LOWER INCISORS
 In general, removal of lower incisors should be avoided as the inter-canine
width tend to decrease which can result in :
- Crowding development in the upper labial segment.
- Overjet increasing.
 Situations need to extract the teeth:
- Lower incisors is grossly displaced from the arch form or ectopic and
space is required to align the teeth.
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21. UPPER INCISORS
 Upper incisors are rarely the extraction of choice to treat a malocclusion.
 Situations need to extract the teeth:
- Long term prognosis of an incisor is poor, for example;
The incisor is non vital, root filled, dilacerated or of abnormal form,
the tooth should be considered for extraction as part of the orthodontic
treatment plan
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22. CANINES
 These teeth are rarely considered for extraction unless very ectopic
because:
- The loss of a canine makes canine guidance impossible and may
compromise a good functional occlusal result.
- Contact between a premolar and lateral incisor is often poor and canines
can act as ideal abutment teeth because of their long root
length and resistance to periodontal problems.
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24. PREMOLARS
 Premolars are often ideal for the relief of both anterior and posterior
crowding
 The first and second premolars have similar crown forms;
which means that an acceptable contact point can be achieved between the
remaining premolar and the adjacent molar and canine.
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26. FIRST MOLARS
 First molars extraction requires careful planning because;
Their position in the arch means that whilst relief of premolar
crowding is achieved the space created is far from the site of any
incisor crowding or overjet reduction.
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27. FIRST MOLAR (CONTD..)
 In general, if a lower first molar is to be extracted, the upper molar on the
same side should also be extracted (compensating extraction).
-This prevents unwanted over eruption of the upper first molar and
the upper second molar will usually erupt into a good position
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28. FIRST MOLAR (CONTD..)
 However, if an upper first molar is to be extracted, the lower counterpart is
usually left in situ.
- The lower second molar behaves unpredictably and rarely achieves
good spontaneous alignment
- Lower molars over erupt less than upper molars and will not interfere
with the generally good progress made by upper second molars.
Therefore, If the case has no crowding, then balancing extractions
should not be considered
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29. SECOND MOLARS
 Role of loss of second molars in orthodontic treatment by Thomas*
 Second molar loss may be undertaken under the following circumstances:
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30. SECOND MOLAR (CONTD..)
 However, the potential disadvantages of second molar extraction are :
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31. THIRD MOLARS
 Whilst extraction of wisdom teeth for orthodontic purposes is rare, these
teeth should be included in the treatment planning.
 The incidence of impaction of third molars varies widely.
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32.  Many factors influence the choice of teeth for extraction
 Careful treatment planning in conjunction with good patient cooperation,
appliance selection and management of the treatment are essential if an
acceptable, aesthetic and functional occlusion is to be achieved.
(Reference: H. Travess et al. (2004). Extractions in orthodontics. BDJ, 196(4), 195-203.)
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CONCLUSION

33. THANK YOU!
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