The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078
2. 2
Increased ability to move teeth under better control: ever-
expanding choice of extraction.
Factors affecting choice of extraction
1. Treatment objectives
2. Type of malocclusion
3. Esthetics (large chin button, prominent nose)
4. Growth pattern.
5. Conditions of teeth.(caries, multifilled teeth,
impacted, ectopic, severe rotation)
6. Health of supporting tissues.
www.indiandentalacademy.com
3. 3
Facial profile alteration:
Maxi retraction of U&L anteriors: 4’s
Lesser retraction in lower face: U4’s and L5’s
Less overall retraction: 5’s or 6’s.
Deep anterior overbite:
Closer.( Mechanically easier to level, as spaces are
closed). incisors – min time and effort.
Open bite:
5 or 6 Xn. Accentuate the curve of Spee.
GRABER: Removal of 5s in mandibular arch preferable.
‘.’ reduces the tendency of relapse of openbite &lingually
inclined incisors seen occasionally with Xn of 4s.
www.indiandentalacademy.com
5. 5
Incisor Extraction:
Mandibular incisors- therapeutic importance
1st sign of incipient malocclusion
Difficult to treat as they relapse easily.
Not a new idea.
Jackson (1904)
Riedel(1975) : Xn of lower
Incisors
Angle:
Inexcusable. Disharmony b/w
Occlusal planes, abnormal overbite
www.indiandentalacademy.com
6. 6
Incisor extraction:
Indications:-
For mandibular incisors:
Extreme crowding / protrusion.
Gingival recession & loss of
overlying bone on labial surface.
Lateral incisors severely # in
young children.
Discrepancy in sizes of U & L
incisors themselves, 1 incisor can
be removed.
Reidel- Rx time reduced.
min facial change.
www.indiandentalacademy.com
7. 7
Incisor extraction:
Advantages:
1. Maintains/ reduces intercanine
width
2. General arch form is maintained
– greater stability
3. Retention period- less
4. Anterior segments can be
retracted readily, if needed.
5. Immediate solid tooth support of
entire buccal segments.
6. Easy reduction of
overbite, reshaping
7. Mechanotherapy is simplified.
Space closure quick.www.indiandentalacademy.com
8. 8
Incisor extraction:
Disadvantages:-
Reopening of space . Central Incisor.
Danger of creating a tooth size discrepancy.
1 incisor Xn- deepbite- if normal tooth size
relationship is present before Xn.
Color difference of canine.
www.indiandentalacademy.com
9. 9
Upper Incisor Extraction:
Rarely indicated.
Unfavorable impaction of U incisor.
Bu/Li blocked out lateral, with good contact b/w central
and canine.
Congenital missing of 1 lateral incisor
Dilacerated tooth.
Trauma, caries & periodontal disease
Gardiner et al:
U crowding, mesial displacement of root apices
of U3 - Xn of lateral incisor.
www.indiandentalacademy.com
10. 10
Summarize:
Incisor Xn not often.
Possibility must always be considered.
Careful planning with diagnostic setup
www.indiandentalacademy.com
11. 11
Extraction of Canines:
Not extracted.
Long path of eruption.
Conditions where indicated:
Impossible to bring in alignment.
Gross displacement Bu/Li
4 in contact with 2 & does not show palatal cusp.
Decision : position of apex.
www.indiandentalacademy.com
12. 12
Where teeth should be positioned in the face and jaws and
how to get them there---Thomas Creekmore JCO sep 1997
www.indiandentalacademy.com
17. 17
Ist Molar Extraction:
Avoided:
Not provide adequate space in the ant region.
5 & 7 may tip in the Xn space.
Deepening of bite.
Masticatory efficiency.
www.indiandentalacademy.com
18. 18
Carious- beyond restoration
RCTreated, - than a perfectly good premolar.
Multi filled teeth- crown.
Premature Xn of 6, to preserve symmetry.
Facial considerations: large chin buttons&/ prominent
nose
(rationale: farther back less facial change)
Open bite cases.
Indications:
www.indiandentalacademy.com
19. 19
Ist Molar Extraction:
Not to allow U7 locked behind L7.
Horizontal elastics – until danger of locking has passed.
Mesially inclined 7, lesser degree of anchor bend.
Wilkinson’s Extraction: 1942
8 ½ to 9 ½ yrs. Extraction of all Ist molars.
Basis:
•Additional space for eruption of 8s.
•Crowding of lower arch minimized.
•Disadvantages-
www.indiandentalacademy.com
20. 20
Single arch extraction – U 6 or what to do
when non extraction treatment fails.
Raleigh Williams. AJO 1979
Class II div 1 with perfect lower arch alignment but growth
expectation inadequate.
Class II div 1 active growth over. Pt non cooperative.
Class II div 1 with good lower arch over basal bone, with
some growth expectation.
Class II div 1 with mild open bite.
www.indiandentalacademy.com
21. 21
Problems with Xn of 4s:
Tipping, opening of space (5 small to fill the space)
Mesial tipping of 6, hanging palatal cusp
Avoided with 6 Xn.
Good molar relation.
U 4 occlude with L4
8s erupt normally.
Min patient cooperation
Stable results.
Tuberosity not crowded.
Results similar to nonext.
Rx duration is reduced.
Profile maintained.
Open bite correction
www.indiandentalacademy.com
22. 22
2nd MOLAR EXTRACTION:
David W.Liddle- AJO 1977
Malocclusion: potential force by developing 7,8.
Xn of 7s to intercept this forward force.
4 Xn: treating the effect and not the cause.
10-12mm of space :satisfies arch length problem, not
apparent when patient smiles.
91% 7 Xn.
6 move distally in response to pressure.
Over compressed CT fibers- move 3 &4 to a more normal
occlusion.
www.indiandentalacademy.com
23. 23
2nd MOLAR EXTRACTION:
ADVANTAGES AND INDICATIONS
Disimpaction of 3rd molars, faster eruption
Prevention of “dished-in” at the end of facial growth
Prevention of late incisor imbrication
Facilitation of 1st molar distalization
Distal movement only as needed to correct the overjet
Fewer “residual”spaces at the end of Rx
Good functional occlusion
Overbite reduction.
www.indiandentalacademy.com
24. 24
Indications:
Chipman:
Xn 7 - caries, ectopic, rotated.
Mild – moderate discrepancy with good profile.
Crowding in tuberosity area ,with a need for distal
movement of 1st molar.
Lehman - preconditions
8 in favorable angulation 15-30*angle to the long
axis of the 1st molar.
Normal in size/shape & root area is sufficient w.r.t
2nd molar.
No congenitally missing teeth.
www.indiandentalacademy.com
25. 25
Disadvantages:
Too much tooth substance removed in Cl I mal occlusion
with mild crowding.
Location far from area of concern.
No help in correction of A-P discrepancy without patient
cooperation .
Possible impaction of 3rd molars even with 2nd molar Xn
Unacceptable positions of erupted 3rd molars –second, late
stage of fixed therapy.
9-20% missing 3rd molars.
www.indiandentalacademy.com
26. 26
Timing for mandibular 2nd molar extraction:
Kokich:
1. 3rd molar crowns completely formed, Xn before
roots begin to develop
2. 30*to the occlusal plane
3. 3rd molars in close proximity to 2nd molar-drift.
Halderson, Huggins, Lehman and Smith.
Before radiographic evidence of root formn.(12-14yrs)
Consensus opinion: as soon as 2nd molar erupts.
angulation.
www.indiandentalacademy.com
27. 27
3rd Molar Extraction:
Xn to prevent lower anterior crowding?
Distal movement of 6,7– impaction of 8.
Pain
Contraindications:
1st or 2nd molars are extracted.
www.indiandentalacademy.com
28. 28
The Effect of Different Extraction sites upon
incisor retraction. Raliegh Williams et al AJO 1976
Relation b/w root surface area and Xn site selection upon
incisor retraction.
Efficient mechanotherapy.
Diagnostic line.
Larger the root surface area, greater the resistance to
movement.
www.indiandentalacademy.com
30. 30
Conclusion:
Location of the Xn site-
Root surface area.
Predict incisor retraction.
Should be considered in diagnosis, so that a
desired Rx goal for the final position of incisors
within the facial profile can be achieved.
www.indiandentalacademy.com
31. 31
Orthodontic treatment may include extractions of
any tooth in the arch.
Based on sound diagnosis, treatment objectives.
www.indiandentalacademy.com
32. 32
“Different extractions for different malocclusions” – Sidney
Brandt, Safirstein AJO 1975
Extractions in Orthodontics- Nagalakshmi & Ashima
Valiathan JICD vol 37 1995
Single arch extraction- upper first molars or what to do when
nonextraction treatment fails- Raleigh Williams AJO oct
1979
Second molar extractions: A review – Samir Bishara, AJO-
DO 1986 may
Second molar extraction in orthodontic treatment- David
W. Liddle AJO dec 1977
Third Molars: A review Samir E. Bishara AJO feb 1983
References:
www.indiandentalacademy.com
33. 33
References:
The effect of different extraction sites upon incisor
retraction- Raleigh Williams & Hosila AJO 1976
Where teeth should be positioned in the face and jaws and
how to get them there---Thomas Creekmore JCO sep
1997
Class II subdivision treatment success rate with symmetric
and asymmetric extraction protocols- Guilherme Jansson,
Dainesi, Fernando. AJO-DO sep 2003
www.indiandentalacademy.com
34. 34
Thank you
For more details please visit
www.indiandentalacademy.com
www.indiandentalacademy.com