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Extractions vs non extraction debate
1. EXTRACTION vs NON EXTRACTION
IN ORTHODONTICS
5/09/2017
Dr.Arpana shekhawat
2ND
M.D.S
Department of Orthodontics&Dentofacial
Orthopaedics,GDC,jaipur.
3. INTRODUCTION
• Generally there are three reasons to extract
the teeth;
1.To provide space for the alignment of
crowded teeth.
2.For the retraction of protruded teeth.
3.For camouflaging the skeletal class II and
class III malocclusions.
4. 4
The Great Extraction controversy
• Extraction of deciduous teeth- ancient times
• Celsus, Fauchard- recommended
• Controversy- permanent teeth extraction
• Hunter- 17th
century- opposed- inhibited growth
• Early 1800s- extraction of 1st
premolars- Class II div 1
malocclusion
• Delabarre- 1818- It is much easier to extract teeth
than to determine if it is absolutely necessary
5. 5
• Kingsley- gave up
• Davenport- 1887- loss of important organs
• Case- 1893- reintroduced- though arches
could be expanded- neither esthetics nor
stability satisfactory in the long run
Although done only in severe cases- 6%
• Angle- 6th
and 7th
publications- non extraction
6. b. Wolff’s Law of bone:
Bone trabeculae were arranged in response to
stress lines on the bone.
7. This led Angle to 2 key concepts:
I. Skeletal growth could be readily influenced by
external pressure.
II.If teeth were placed in proper occlusion,
forces transmitted to teeth would cause bone
to grow around them and so stabilizing them
in a new position even if great deal of arch
expansion had occurred.
8. 8
• Case- 1911- article “the question of extraction
in orthodontia” (Dental cosmos 1912)
• Martin Dewey- challenged Case
• Angle followers- won the day- 30 years-
nonextraction
• John Mershon, Joseph Johnson, George
Crozat- nonextraction
9. These concepts did not go unchallenged.
Calvin Case argued that although arches
could always be expanded, neither esthetics
nor the stability would be satisfactory in
long term in many patients.
This controversy culminated in debate
between Angle’s student Dewey and Case.
Angle’s followers won the day.
10. 2. THE RE-INTRODUCTION OF EXTRACTION IN
THE MID 20TH
CENTURY.
Relapse after non-extraction treatment was
frequently observed by 1930.
Charles Tweed & Raymond Begg, both adapted
‘EXTRACTION WHEN NECESSARY’ approach and
treated their patient with this philosophy.
They found that occlusion was stable and
esthetics was improved.
11. 11
Re-introduction of extraction in
mid-century
• 1930- relapse frequently observed
• First to analyze relapse scientifically – Alex
Lundstrom - Stockholm, Sweden
• Apical base is deficient- crowded teeth
corrected by orthodontic means- relapse
12. 12
• By the early 1960s- more than 50% American
patients- extraction treatment (not always
first premolars)
• Concept- orthodontic treatment could not
affect facial growth
• Hereditary cause
• Lack of proximal wear
15. 15
• Reason for decrease in extraction cases
• Collapse of expanded arches- stable occlusion-
no guarantee
Extraction – may not be stable- no reason to
sacrifice teeth
17. 17
What is a borderline case?
• Buchin- Borderline case- when extraction of teeth is
required to reach stable and functional occlusion ,
but patient has good facial esthetics that could be
disturbed by extractions
characteristics:
• • Absence of dental or craniofacial anomalies.
• • Permanent dentition.
• • Healthy periodontium.
• • Normal anteroposterior relationship between maxilla and mandible (skeletal
Class I).
18. 18
Criteria for extraction
• Arch length discrepancy
• Facial esthetics:
- Will flattening middle and lower third of face
improve esthetics?
- Will soft tissue drape be representative of the
skeletal scaffold, how much will chin and nose
grow?
22. EVALUATION OF DIAGNOSTIC
ELEMENTS FOR EXTRACTION
CLINICAL
PARAMETERS
I. FACIAL
APPEARANCE
II. SOFT TISSUE
PROFILE
III. MIDLINE
IV. GROWTH
MODEL ANALYSIS
I. CAREY’S MODEL
ANALYSIS
II. CURVE OF SPEE
III. BOLTON
DISCREPANCY
IV. IRREGULARITY
INDEX
CEPHALOMETRIC
VARIABLES
VERTICAL FACIAL
PROPORTIONS.
I. FMA
II. SN-MP
III. JARABAK RATIO
LOWER INCISOR
POSITION.
I. IMPA
II. FMIA
III. LOWER INCISOR
TO A-Pog
DISTANCE
23. CLINICAL PARAMETERS
I. FACIAL APPEARANCE:
• Facial appearance -consideration -planning
orthodontic treatment.
• Genetic makeup,
• Environmental influences,
• and cultural background.
• How extractions vs arch expansion affects
facial appearance is a major concern for
orthodontists.
24. II. SOFT TISSUE PROFILE.
• How extraction vs non-extraction therapy
affects the profile also is a concern.
• Extraction therapy is sometimes believed
to be detrimental to the profile.
25. Facial appearance of
the patient
following treatment
after 1Yrs and 9
months
P R E - T R E A T M E N T
P O S T - T R E A T M E N T 25
26. • This is important because, if a patient has
proclined incisors or proclined incisors with
crowding.
• it would be virtually impossible to improve
the anteroposterior position of the teeth and
the patient’s profile without extractions.
27. III. MIDLINE:
• According to Strang , the harmonic
positioning of the midlines relative to each
other and to the face is what characterizes
normal occlusion.
• Any variation in this combination is
indicative of improper relationship between
the teeth or dental arches.
28. • This requires a careful diagnosis because
properly assessing the causes behind midline
shifts allows professionals to use unique
mechanics and asymmetric extractions.
• Patients presenting with severe dental
midline deviation relative to the face
require tooth extractions.
29. IV. GROWTH STATUS.
• In malocclusions with skeletal
discrepancies it is crucial—for the
diagnosis and prognosis of the case—to
check whether the patient is still
undergoing significant facial growth.
• If a malocclusion can be corrected with
growth response (growth redirection),
clinicians can handle the case without
extractions.
30. MODEL ANALYSIS
I. CAREY’S ANALYSIS:
• First determine the degree of discrepancy
between bone and tooth structure.
• If the discrepancy is 2.5 mm. or less, we do
not extract.
• If it is 2.5 to 5.0 mm., we extract the
second premolars, whenever possible, to
obtain better esthetics.
• If it is more than 5 mm., we extract the
first premolars.
31. • If the discrepancy is extreme (5 mm. or
more), in the lower arch and mild in the
upper, we extract the lower first and
upper second premolars, and vice versa.
• When the discrepancy is confined to the
maxillary arch, two upper first or second
premolars are removed, the choice
depending upon the degree of the
deficiency.
32. II. CURVE OF SPEE:
• Levelling the curve increases incisor protrusion.
• Recent studies conclude the real effect to be
closer to 1:3; for every 3 mm of curve levelled,
arch circumference increases 1 mm.
• The deeper the Curve of Spee, the greater the
need for extraction.
33. III. BOLTON DISCREPANCY.
• An interarch tooth-size discrepancy may provide
incentive to extract in order to establish a proper
occlusion. This diagnostic variable has been
popularized as the Bolton discrepancy.
• Clinicians have utilized interproximal reduction to
resolve interarch tooth size discrepancies.
34. • Bolton noted a 4 mm limit to anterior
reduction. Thus, extraction may be necessary
to resolve a discrepancy greater than this.
35. CEPHALOMETRIC VARIABLES
VERTICAL FACIAL PROPORTIONS:
I. SN-MANDIBULAR PLANE ANGLE(SN-MP)
• Schudy utilized the angle formed at the
intersection of the sella-nasion and mandibular
planes (SN-MP)to aid in his assessments, and
found the value of 33 degrees to be average for
balanced vertical facial types, with a range of 31
to 34 degrees.
36. II. FRANKFORT MANDIBULAR PLANE ANGLE(FMA).
• The FMA provides an additional vertical
appraisal to the SN-MP measurement.
• A normal value for the FMA is in the range of 20
to 30 degrees.
• Values above these normal ranges are
associated with skeletal open bite, whereas
values below are typically associated with
skeletal deep bite.
37. III. JARABACK RATIO:
• The PFH (distance between sella and
gonion) is divided by the AFH (distance
between nasion and menton).
• The normal value is 61-69%.
• Less than 61% suggests a skeletal open
bite; greater than 69% indicates a skeletal
deep bite.
38. LOWER INCISOR POSITION:
I. INCISOR MANDIBULAR PLANE ANGLE(IMPA):
• Charles Tweed used the orientation of the
mandibular incisor to aid in treatment planning
to create facial balance and harmony.
• He noted a need for “upright” and “vertical”
lower incisors.
• Margolis proposed the incisor mandibular plane
angle (IMPA) to quantitatively define these two
qualities.
39. • He proposed IMPA to be 90+/-3 degrees
in normal, balanced faces.
• According to Tweed, this value can range
between 85 and 95 degrees, and vary
according to ethnicity.
• Values above this range are indicative of
extraction to improve functional and
esthetic imbalance.
40. II. FRANKFORT MANDIBULAR INCISOR
ANGLE(FMIA):
• The norm for the angle formed by the
intersection of the Frankfort plane and the long
axis of the lower incisor is 60-70°.
• A value less than 60° indicates proclination of
the lower incisors, whereas a value greater than
70° suggests that the lower incisors are
retroclined.
41. III. LOWER INCISOR TO A-Pog DISTANCE:
• McNamara found the proper position of
the mandibular incisor to be 1 to 3
millimeters anterior to the line from
point A to Pogonion (A-Pog) in a well-
balanced face, regardless of age.
44. CHOICE OF INDIVIDUAL TEETH
1. UPPER INCISOR EXTRACTION:
INDICATIONS:
• Unfavorably impacted incisor.
• Buccally or lingually blocked out lateral
incisor with good contact between central
incisor and canine.
• Congenitally missing one of lateral incisor,
opposite incisor may require extraction to
maintain arch symmetry.
45. • Grossly carious incisor.
• Malformed incisor that can not be
restored.
• Trauma or irreparable damage.
• An incisor with dilacerated root.
46. 2. LOWER INCISOR EXTRACTION:
• In 1905, Jackson described a case in which
two lower incisors were extracted at
different times to relieve mandibular
crowding.
• Hahn(1942) advocated the removal of a
mandibular incisor to close the space and
thus reduce the anterior dentition.
47. INDICATIONS:
(Permanent dentition,Minimal growth
potential, Class I molar relationship,
Harmonious soft-tissue profile,Minimal-to-
moderate overbite, Little or no crowding in
the maxillary arch)
• Existing Bolton discrepancy
• Tooth-size-arch-length discrepancy of more
than 5mm in the anterior region
48. WHICH INCISOR TO BE REMOVED?
• Periodontal conditions
• gingival recession
• any restorations,including endodontic
treatment.
• Extraction of a lateral incisor is generally
preferred because it is less visible from the
front.
49. 3. CANINE EXTRACTION INDICATIONS:
•Extremely unfavourable cuspid position.
•Tooth position unfavourable for orthodontic
movement.
•Ankylosed tooth.
•Internal or external root resorption.
•Severe dilaceration.
51. 4. PREMOLAR EXTRACTION:
• In 1949, Nance stated that the term extraction
had, at that time, become synonymous with
the removal of all four first premolars.
Augmenting anchorage, maximum lip
retraction, better contact between the canines
and second premolars
• first premolars are nearer to anterior
crowding are some of the reasons behind
favouring their extraction.
52. 1ST
PREMOLAR
EXTRACTION
2ND
PREMOLAR
EXTRACITON
ANCHORAGE NOT SIGNIFICANT NOT SIGNIFICANT
LIP RETRACTION NOT SIGNIFICANT NOT SIGNIFICANT
FACIAL VERTICAL
DIMMENSION
NOT SIGNIFICANT NOT SIGNIFICANT
TOOTH SIZE
DISCREPANCY
MORE EVIDENT LESS EVIDENT
CLINICAL
CONSIDERATIONS
NOT FAVOURABLE FAVOURABLE
MOTHER NATURE’S
RULE
DOESN’T ALLOW ALLOW
53. Second premolars
• The indications for extraction of second premolars include the
following:
1. congenital absence of the second premolars and crowding of
the arch;
2. hypoplasia of the second premolars and crowding of the arch;
3. severe displacement of the second premolar;
4. mild to moderate crowding (2–4 mm per quadrant);
5. where space closure by forward movement of the molars
rather than retraction of the labial segments is indicated.
54. Second premolars
• Extraction of the second premolars is
preferable to extraction of the first premolars
in cases with mild to moderate crowding as
their extraction alters the anchorage balance,
favouring space closure by forward movement
of the molars.
55. 5. 1ST
MOLAR EXTRACTION:
• “First permanent molar extractions doubling
the treatment time and halving the
prognosis” was the phrase coined by Mills.
• Daugaard-Jensen suggested that first molar
cases are no more time consuming than 4
premolar cases.
• Williams and Hosila highlighted the fact that
first molar extraction cases are likely to have
less effect on the profile than premolar
extraction cases.
56. INDICATIONS:( Sandler et al 2000)
• Extensively carious first molars.
• Hypoplastic first molars.
• Heavily filled first molars where premolars are
perfectly healthy.
• Apical pathoses or root canal treated first
molars.
• Crowding at the distal part of the arches and
wisdom teeth reasonably positioned.
• High maxillary/mandibular planes angle
(Anterior open bite cases).
57. • TIMING OF EXTRACTIONS:
If the upper second molars are unerupted at the
time of extraction of the upper first molars, they
will almost completely replace them, thus
contributing little space for correction of the
malocclusion.
If there is a space requirement in the upper arch
therefore, extraction of the first molars must be
delayed until the second molars have erupted
sufficiently to allow a palatal arch with Nance
button or headgear to be placed.
58. 6. 2ND
MOLAR EXTRACTION:
INDICATIONS(Lehmann 1979)
• The second molars are severely carious,
ectopically erupted, or severely rotated.
• Skeletal Class I malocclusions with arch length
discrepancy in the distal part of the arch or with
mild anterior crowding and
• In Class II "skeletal" cases with only mild
crowding of the mandibular arch.
59. ADVANTAGES:
• Disimpaction of third molars
• Faster eruption of third molars
• Prevention of "dished-in" appearance of the
face at the end of facial growth
• Prevention of "late" incisor imbrication
• Facilitation of first molar distal movement
60. TIMINGS OF EXTRACTION: (Kokich 1983)
• The third molar crowns should be
completely formed but extractions should be
performed before the roots begin to develop;
• The axial inclination of the third molar buds
should not be greater than 30 ° relative to
the occlusal plane;
• The mandibular third molar should be in
close proximity to the second molar roots to
ensure adequate mesial drift of the third
molar as it erupts.
62. 62
• At what point have incisors moved too far
forward?
• >4 mm lip separation at rest- incompetent lips
63. 63
- Size of nose and chin
individual with a large nose or chin, it is better to
have fuller lips, provided it does not diminish the
mentolabial sulcus too much.
• For best aesthetics, the lower lip should be at least
as prominent as the chin. Retroclining the lower
incisors too much may cause the lower lip to fall back
leading to a concave profile which is unaesthetic.
•
67. 67
Expansion by opening the midpalatal suture-
lower arch will follow upper
But if limiting factor is cheek pressure- no
significant difference
Excessive expansion- fenestration, dehiscence of
molar, premolar roots- 50% skeletal, 50%
dental movement
12mm expansion- 3mm per side dental
69. 69
• Final set of guidelines:
- If extraction spaces can be closed without
retracting too much, expansion carried out
without proclining too much..
Esthetics not affected a great deal
For masticatory function and oral health, it
makes no difference either way
70. 70
Reproximation
• “Stripping is defined as the act of clinically
removing part of the dental enamel from an
interproximal contact area.” (AO 2007).
• Sheridan and Fillion 1985…..slenderization
techchnique
currently in use
71. 71
INDICATIONS:
• Mild to moderate crowding in anterior areas….class
I
• Good oral hygiene
• Mild tooth material excess …. Bolton’s analysis
• Post treatment relapse
• Tooth shape deviations (Peck & peck index)
72. 72
CONTRAINDICATIONS
• SMALL TEETH
• RESTORED TEETH WITH NORMAL SHAPE
• ENAMEL HYPOPLASIA
• POOR ORAL HYGIENE
• HIGH CARIES & PLAQUE INDEX
• RECTANGULAR SHAPED TEETH
• VERY YOUNG PATIENTS
73. 73
Approximately 50% of the
interproximal enamel can be safely
removed ( Boese -AO 1980)
Fillión : Mesial surface of the first right molar
to the same surface of the left molar
10.2 mm of space in the maxilla
8.6 mm in the mandible.
75. 75
“Air rotor stripping is a technique to remove controlled
amounts of enamel in the posterior segments to gain arch
length for retracting and aligning anterior teeth”(AJO FEB’94)
-Primarily in the buccal quadrants (upto 8mm space gain)
- Treatment philosopy …… Difficulties in adult extraction
Instability of expansion
76. 76
Molar Distalization
• Patient with Class II molar- no obvious skeletal
deficiency
• Acceptable facial esthetics
• Upper incisors – normal, retroclined
• Canines bucally blocked out
• Minimal arch length discrepancy
• Low MPA
77. 77
Negatives of extractions
• Tendency towards recrowding in lower
anterior region
• Deepening of anterior overbite
• Incomplete contact points, improper marginal
ridges, plunger cusps- perio problems
• Streamlining of face- large nose, big chin
point, retrusive dentition
78. 78
Comparison of the changes in facial profile after
orthodontic treatment with and without extractions, in
"borderline" Class I crowding female patients
- Arch length discrepancy - 3 to 7mm
- No severe incisor and lip protrusion and no
severe vertical discrepancy
79. 79
- Soft tissue differences between two groups - end of
treatment - more protruded lower lip in non-
extraction patients
- Significant hard tissue difference between two
groups - only limited to- more labial inclination of
the incisors in non-extraction patients
- Borderline cases can be treated with satisfactory
occlusions and esthetics either way. This is true if
expansion is managed so as not to produce too much
protrusion, or space closure after extraction is
controlled so as not to produce too much incisor
retraction
80. 80
• Are we more concerned with the face rather
than the patient?
• Calvin Case:
No matter how irregular the teeth, however bunched,
malaligned or malposed, they can always be placed
in their respective places in the arches and in normal
occlusion. Therefore, so far as the relations of the
teeth to each other are concerned, no dental
malposition should be taken as a basis for extraction.
The only excuse, then, for the extraction of savable
teeth must be that it is inexpedient or impossible to
correct their positions in that way without producing
facial protrusion."
- Stability
81. 81
• Facial balance with the major objective- clinical
experience
• It is always a problem when someone asks a
question and uses a term that has meaning to him
but perhaps a different meaning to the man
answering the question. We refer to clinical
experience and diagnostic criteria. To me, clinical
experience is only a measure of the operator's
ability. It varies with each of us. Our clinical
experience is "what we can do".
82. 82
• Diagnostic criteria are generally specifics that we
take from someone else such as a Tweed triangle or
a Downs analysis. In our working practices we have
to give preference to the clinical experience we have
attained over the numbers that someone may have
given us. So, if we do have a conflict, I think it is
perfectly legitimate to use clinical experience or
therapeutic treatment in preference to some
arbitrary scale of which we are not completely sure.
It may change tomorrow.
83. 83
Summary- Century Orthodontics
• All or nothing nature of premolar extractions-
different orthodontists – conflicting views
• Each doctor has different gray between
extraction and nonextraction
84. 84
• Borderline cases- no right answers
• Try to avoid extractions as much as possible
• Esthetics, stability
• Conflict between esthetics, stability- esthetics
• Not that flat profiles, crowding-
nonextractions
85. 85
• Contrary to nonextraction believers- no TMDs
• Well treated extractions- no adverse effect on
facial profiles
• Visualize patients with flat profiles with
premolar extractions
• Truth- tight facial structures – crowding-
extractions- not vice versa
86. 86
• Most dished in – nonextraction
• dark buccal corridors and a narrow smile are
not “caused” by premolar extractions.
87. 87
• Good selling point for premolar extractions-
moderate crowding, well formed and
positioned 3rd
molars
• no guarantee can be made that the thirds will
always come in with enough room
88. 88
• Great deal of confusion about early expansion
treatment
• Important difference between expanding a
constricted upper arch to match a normal
lower arch
• significantly expanding both arches in a
patient whose arches may be narrow, but are
in a normal transverse occlusal relationship to
each other
89. 89
• Possible to upright lingually verted lower posterior
arches (which may have collapsed in, to compensate
for a narrow maxillary arch), it is not possible to
expand the mandibular basal bone - is no suture to
distract as in the maxilla
• One of the most established - stability of the lower
inter-canine width
• Expansion beyond the original width - almost a
guarantee of collapse and recrowding
90. 90
In an attempt to avoid first premolar extractions,
various alternatives can be considered:
- Expanding the arch, especially in flat-faced
individual- preferable to extractions - unstable
correction - retention will be needed
- Patients with good posterior occlusion, good upper
arch with relatively small upper incisors, moderately
severe lower crowding, minimal overbite - extraction
of lower incisor
Should be evaluated very carefully- untreatable
problem with excessive overjet/overbite
91. 91
• Interproximal enamel reduction (IPR) can
provide a moderate amount of room but
should be reserved for older patients.
Excessive IPR as an initial treatment
complicates the orthodontist’s ability to
correct minor relapses in the future.
92. 92
• Consider extraction of second premolars rather than
first premolars.
• Theoretically- reduces the amount of anterior
retraction when only some space is needed for
crowding and facial profile is acceptable
• Works best when second premolars resemble the
first, but large, molar-like second premolars may
provide too much room and small, canine-like first
premolars may not work against first molars
93. 93
• No right answers in borderline cases
• Both T/t performed by competent
orthodontists- satisfactory results- neither
perfect
94. 94
• Borderline cases- greatest responsibility
• Sensitive
• if the wrong decision is made or if the
mechanics are not carried out correctly, one
really stands to do a great disservice to the
patient.
95. 95
Extractions are just a tool,
not good or bad in
themselves. Used right, they
improve the quality of
treatment, used wrong they
may create a poor result.
97. MCQ:
1.Extraction of teeth in conjunction to orthodontic treatment is
necessary in order to
(A)To relieve crowding in the arches especially when jaws are
not large enough to accommodate all the teeth
(B)To achieve proper sagittal inter-arch relationship
(C)Just as a procedure of orthodontics
(D)Both A and B
2. The decision of extraction is based on the following factors
(A)Patient’s age
(B)Sex of the patient
(C) The amount of space needed for tooth alignment
(D) All of the above 97
98. 3.The decision to opt for extraction should only be made
(A)After careful clinical evaluation
(B)After model analysis done
(C)After cephalometric tracing done
(D)All of the above
4. Injudicious extraction of teeth can cause
(A)Arch collapse
(B)Deep overbite
(C) Spacing and tissue damage
(D) All of the above
98
99. 5.Who was the major proponent of “ Non Extraction
Philosophy”
(A)Edward H Angle
(B)Calvin Case
(C)John Hunter
(D)All of the above
6. Who introduced the concept of extraction as a part of
orthodontic treatment.
(A)Calvin Case
(B)Charles Tweed
(C)Angle
(D)Jhon Hunter
99
100. 7.Most commonly extracted teeth for orthodontic purpose are
(A)Maxillary first molars
(B)Maxillary and mandibular premolars
(C)Mandibular incisors
(D)Maxillary incisors
8. The tooth most rarely extracted as a part of orthodontic treatment
(A)Maxillary central incisors
(B)Maxillary third molars
(C)Mandibular third molar
(D)Maxillary and mandibular premolars
100
101. 9. What are the different extraction procedures?
(A)Balanced extraction
(B)Compensatory extraction
(C)Enforced extraction
(D)All of the above
10. Compensatory extraction refers to
(A)Extraction of tooth in the opposite jaw to the same teeth
group
(B)The extraction of a tooth in the same jaw to the same teeth
group
(C)The extraction of a tooth in the cotralateral side to the same
teeth group
(D)None of the above 101
