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2. Various prescriptions
Part I
• Andrew’s Straight Wire Appliance (SWA),
• Roth Prescription,
• The Level Anchorage System,
• Alexander’s The Vari Simplex discipline.
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3. Various prescriptions
Part II
• Hilgers – Linear Dynamic System (Bio-
Progressive system).
• MBT System.
• Viazis – The Bioefficient Therapy.
• Bowman and Aldo Carano: The Butterfly
System.
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5. An evolution from the edge wise technique
introduced by Dr’s. Robert Ricketts and Ruel
Bench, who combined contemporary
edgewise mechanics with solid diagnostic
principles and an innovative approach to
sectional mechanics.
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6. Considerations for Design
1. Type and severity of malocclusion:
Class II cases medially rotated upper molar,
medially tipped lower molar, forward buccal
segments and tapered upper arch – rebound –
Overcorrection.
2. General approach to mechanics:
Contracted arches in extraction cases –
detorque.
Expanded arches in non extraction cases –
torque.
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7. 3. Sizes of final arches:
For each .001 " tolerance between archwire
and slot, as much as 4° of torquing effectiveness
is lost.
Torquing - full-size continuous archwire.
4. Timing of torque control:
Torque control from the start as efficient to
bring the tooth directly to its over treated goal.
Early set-up of the posterior occlusion provides
the framework for proper buccal and anterior
tooth positions. www.indiandentalacademy.com
8. 5. Need for overcorrection:
Each tooth has an overcorrected position
that best allows for final settling. Some of these
positions relate to mechanics, others to
rebound.
6. Bracket placement:
The accuracy of bracket placement, the
compensations for occlusal interferences, and
the adaptability of the bracket bases all affect
final tooth positions, especially with direct
bonding. www.indiandentalacademy.com
9. Area to observation – upper cuspid fit with the
lower cuspid-bicuspid embrasure.
Achieved by first setting up the posterior occlusion
by rotating the upper first molar.
But it is difficult to rotate the upper first molar
without first rotating and uprighting the lower
first molar.
Therefore, the key to a Class I buccalTherefore, the key to a Class I buccal
segment is the proper positioning of thesegment is the proper positioning of the
lower first molars.lower first molars.
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10. So, allow the dentition to move directly toward
final positions by establishing a mandibular
occlusal table as early in treatment as possible.
The ability of certain teeth to drift into desired
locations and inability of other teeth to drift
into desired locations.
Understanding of the physiologic rebound allows
to make decisions about tooth locations when
detailing a case.
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11. Criteria for each Tooth
• Ideal orthodontic tooth position.
• Anticipated rebound and required
overcorrection.
• Appliance design features that contribute to
patient comfort, clinical simplicity, and
optimum utility.
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12. Prescription
Mandibular First Molars:
Torque Tip Rotation Thickness
Main slot – 27° – 5° 12° distal Thinnest
Auxiliary slot 0° – 5° 0°
Upper first molar - into a slight mesial tip with
the distobuccal cusp slightly past the plane of
occlusion as distal marginal ridge on the upper
first molar is shallower than the mesial
marginal ridge.
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13. For distal rotation of the upper first molar – the
lower first molar must be rotated distally more
than one would expect.
The contact between the lower first and second
molars is unique. Because of the settling of the
upper first molar to the mesial, there should be
a slight opening in the contact point between
the lower first and second molars to allow the
disto-buccal cusp of the upper first molar to
seat.
Prescription
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14. 2 mechanical factors for mesial rotation:
1. the pull of Class II elastics and
2. the forces used to retract anterior teeth.
Counterbalance these factors by slight over-
rotation.
Prescription
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15. Ideal distal rotation, distobuccal cusp of first
molar is rotated 1/3rd
of distance through mesial
marginal ridge of second molar.
The 12° distal rotation coordinates with a 15°
maxillary molar rotation to avoid conflicting
inclined planes and eliminate the need for
bicuspid and molar offsets.
Prescription
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16. Maxillary First Molars
Torque Tip Rotation Thickness
Main slot -10° 0° 15° distal Thinnest
Auxiliary slot 0° 0° 0°
Prescription
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17. A line drawn through
distobuccal cusp points at the
distal of the opposite cuspid.
This rotation uses the shortest
distance across the
trapezoidal molar, with
shortest arch length in the
upper buccal segment, and
allows seating of the upper
cuspids.
Prescription
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18. 15° distal offset:
First, the tooth morphology requires some offset
for a linear archwire.
Second, the archwire leads away from the tooth
mesiodistally, and the tube's built-in rotation
must be neutral to allow proper rotation.
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19. Third, most Class II cases have mesially rotated
upper first molars that require compensation
with an overcorrected distal rotation.
Fourth, mechanics in Class II and III cases often
involve forces that rotate the upper molar
mesiolingually.
Fifth, a few degrees of offset is lost because of
archwire/slot differential.
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20. The roots be inclined slightly to the
lingual, for occlusal forces.
There is a slight distal root tip as
the upper first molars settle into a
normal Class I occlusion.
The entire upper buccal segment
should have 10° of buccal root
torque to compensate for the
occlusogingival curvature of the
crowns of these teeth.
Prescription
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21. The Auxiliary Tube:
Is offset to the buccal to avoid tissue
impingement. This allows for selective torque
and rotation of the upper first molar with initial
utility arches, and it helps in placement of
auxiliary arches.
The auxiliary tube can be used as the main arch
slot in upper first bicuspid extraction cases
where mesial rotation of the molar is desired.
Prescription
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22. Second Molars
Torque Tip Rotation Thickness
Main slot -10° 0° 12° distal Thinnest
Mandibular -27° -5° 12° distal Thinnest
Prescription
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23. In Class II cases, erupts mesially – areas of
occlusal interference, often causing
disarticulation of the condyle.
Lower second molar:
Tipped distally during treatment because it
will settle mesially as the distobuccal cusp of
the upper first molar settles into the lower first
and second molar embrasure.
Prescription
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24. Upper second molar:
When tipped back slightly and
overcorrected in its Class I position, will settle
in much the same way as the upper first molar.
The same cast tube is used for both maxillary and
mandibular second molars. Difference in
torque, correspond with that of the first molars
to allow proper positioning.
Prescription
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25. Mandibular Second Bicuspids
Torque Tip Thickness
– 17° 0° Thin
Buccal root torque symmetrical with the lower
first and second molars, because their main
cortical bone support is through the external
oblique ridge.
Bracket base be thin to accentuate the buccal
offset of the lower first molar. In extraction
cases it is helpful to have a 5° mesial tip for root
paralleling.
Prescription
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26. Mandibular First Bicuspids
Torque Tip Thickness
– 11° 0° Thin
Transition tooth of the lower arch functions as
both an anterior and a posterior tooth.
The buccal cusp seats in the distal fossa of the
upper first bicuspid.
Prescription
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27. The upper cuspid occludes with the lower first
bicuspid, the lower cuspid, and often the distal
aspect of the lower lateral incisor.
Root support of the lower first bicuspid is mainly
from the lingual.
Buccal root torque in the bracket to passively
accommodate the greater buccal crown
curvature.
Prescription
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28. Prescription
Mandibular Cuspids
Torque Tip Thickness
7° 5° Thin
Cuspid's distobuccal incline articulates with the
mesiolingual incline of the upper cuspid to
create the primary guidance for disarticulation
of the balancing side occlusion.
Therefore, the labial surface would ideally be
angled slightly outward— implying a lingual
root torque.
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29. Prescription
Also advantageous mechanically as the lower
cuspid is moved mesially or distally – especially
in extraction cases, as a tendency to detorque
both arches.
In the vertical plane, the lower cuspid should be
bracketed slightly gingivally to keep it in
contact with the upper cuspid.
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30. Prescription
Mandibular Incisors
Torque Tip Thickness
– 1° 0° Thin
Plays a role in cuspid guidance. The incisal edge
has a short mesial incline and a long, sloping
distal incline.
Allowing for a slight distal root tip of the lower
lateral incisor – stability.www.indiandentalacademy.com
31. Prescription
Bracket Height
Incisal in deep bite cases to assist in bite
opening and intrusion.
Gingival bracket placement in the buccal
segments, this helps level a deep curve of Spee.
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32. Prescription
Maxillary Bicuspids
Torque Tip Thickness
– 7° 0° Thin
If the distal marginal ridge of the upper second
bicuspid is not seated against the
mesiobuccal cusp of the lower first molar, it
is difficult to establish an anterior Class I
relationship.
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33. Prescription
As with the maxillary first molar, buccal root
torque assures that the roots can be slightly
to the lingual and supported by the dense
cortical bone of the palate particularly when
expansion is part of the treatment mechanics.
A mesial root tip of -5° in extraction cases
facilitates root paralleling.
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34. Prescription
Maxillary Cuspids
Torque Tip Thickness
7° 10° Thin
With a 134° intercanine angle, the upper cuspid
should be torqued slightly to the lingual.
The labial inclination is important in supporting
the corners of the mouth and the caninus
complex. www.indiandentalacademy.com
35. Prescription
The relationship between the upper lateral
incisor and the upper cuspid is influenced by
torque.
Torque differential to maintain integrity of the
labial surface contours.
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36. Prescription
Maxillary Incisors
Torque Tip Thickness
Lateral 14° 8° Standard
Central 22° 5° Standard
Brachyfacial – more torque is needed.
Dolichofacial need the torque to prevent
dumping during space closure.
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37. Prescription
Standard thickness:
To keep the upper lateral incisor flush with the
central incisor during the overcorrection process
and then tuck in the lateral incisor during the
retention phase.
To maintain a good contact point with the upper
cuspid, the upper lateral incisor bracket should
be slightly thicker than the upper cuspid
bracket.
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38. In this bracket system, the slot dimensions are
0.018x0.030 inch compared with the standard
0.018x0.025 inch edge wise slot. This was an
evolution from the original Steiner design.
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41. Richard P McLaughlin and John Bennett in
1993.
Third generation of brackets.
Basis – mechanics and force levels should
determine the design of the bracket system
and not vice versa.
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42. Range of Brackets
1. Standard size metal brackets – control
main requirement.
2. Midsize metal brackets – less control, cases
with poor oral hygiene average to small
teeth.
3. Esthetic brackets – older patients.
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43. Shape of Bracket
Rhomboid shape:
Reduces bulk,
Allows reference lines in both horizontal
and vertical planes – assists accuracy.
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44. Torque in Base
CAD factor:
Problem with earlier generation – torque in
base was not possible.
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45. In-out specification
100% fully expressed – archwire fits snugly in the
slot.
Original SWA used.
Upper 2nd
premolars – small crowns in 20% of
cases. 0.5mm thicker brackets for such tooth.
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46. Tip and Torque
Upper Incisors: Tip Torque
Centrals – 40
170
Laterals – 80
100
Lower incisors – 00
60
Tip lesser than SWA – reduces anchorage
decreases tendency of dark triangular spaces
between centrals.
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47. Torque control for Incisors
Upper Torque loss – Class II elastics, better
results in class I and III cases – palatal root
torque.
Even improve esthetics and under torque look.
Lower incisor tend to procline – curve of spee
leveling and relieving crowding – upright them.
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48. Cuspids Tip Torque
upper 80
-70
lower 30
-60
Tip
Additional increase in tip increases anchorage
needs.
Allows for cuspid rise during functional
movements.
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49. Versatility
3 torque options for both the arch canines
Upper 70
, 00
and -70
Lower 60
, 00
and -60
6 factors govern the selection of above torque
1. Arch form,
2. Canine prominence,
3. The extraction decision (tip control),
4. Overbite,
5. Rapid palatal expansion and
6. Agenesis of upper lateral incisor where space is to
be closed. www.indiandentalacademy.com
51. Canine Prominence
00
or positive torqued brackets – canine
prominent and even if gingival recession.
00
for cases with premolar extraction and canine
tipping - - - roots in cancellous bone so tip
control will be easier.
Extraction Decision
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52. Overbite
Class II/2 and deep bite cases need for canine
crowns to move labially but with roots
centered in the bone – with 00
or +60
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53. Rapid palatal expansion
RME results in widening of the upper arch with
secondary widening in lower arch.
To compensate the torque changes – 00
or +60
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54. Agenesis of upper lateral incisor
Invert -70
upper bracket by 1800
so that torque
changes to +70
but tip remains the same.
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55. 1st
Bicuspids
Tip Torque
upper 00
-70
lower 20
-120
00
tip, places the crown in a more upright (in the
direction of class I ) position.
This also requires slightly less distal root
movement which helps to reduces the difficult
anchorage problem in the upper arch.
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56. For lower, the tip is 20
which inclines the crowns
slightly forward (in the direction of class I ).
–120
torque , which helps to upright the crown
facially – common need in cases that require
expansion of upper arch and also in extraction
cases.
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57. 2nd
Bicuspids
Tip Torque
upper 00
-140
lower 20
-170
00
tip – crowns in a more upright position than 20
tip and is more in the direction of class I and
also requires slightly less distal movement
conserving upper area anchorage.
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58. The upper 2nd
bicuspids is often smaller than the
1st
and additional 0.5mm of thickness i.e., in-
out is recommended in the bracket.
If the 2nd
bicuspids have the same size as the 1st
then a 1st
bicuspid bracket is recommended for
the 2nd
bicuspids.
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59. Lower 2nd
bicuspids
The 20
of tip incline the crown slightly forward
towards class I and is consistent.
The recommended torque is less and helps to
torque the crown in a buccal direction such
torquing is often desirable in cases where
upper expansion has been carried out and
also in extraction cases.
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60. 1st Molar
Tip Torque Rotation
Upper 00
-140
10
Lower 20
-200
0
Original SWA tip was 50
.
2 methods of achieving it during treatment.
The author prefer a 00
tip bracket, with the
bands seated more gingivally at the mesial
aspect, but is difficult to position the band like
this accurately. www.indiandentalacademy.com
61. There is a need to push the band up on the
mesial surface and trim band material distal
marginal ridge.
If a 50
bracket is used, and band is seated parallel
to buccal cusp this will result in an effective 100
tip on 1st molar, which is excessive.
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62. Torque consideration
Because of the tendency for the upper palatal
cusp to be extended, thereby creating
interferences, additional buccal root torque is
needed.
Therefore an extra 50
of –ve torque, (i.e., total of
-140
buccal root torque) on the upper 1st
molars.
While this does help the problem of interfering
the palatal cusp it is often necessary to add
buccal root torque to the upper archwire and
to widen it to achieve the desired result.www.indiandentalacademy.com
63. Rotation control
The authors chose to use 10 distal rotation
to create a proper occlusal relationship with
the lower 1st molar.
Class II molar result – for the cases treated to a
class II relationship, a 1st molar bracket with
00
tip, 0 rotation and –140
torque can be used.
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64. Lower 1st molar
Although in many cases –300
torque is
adequate this torque does little to upright lower
molars which are inclined lingually.
For this reason –200
torque is recommended for
lower 1st molar bracket which will result in
uprighting effect on the molars which are
tipped lingually.
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65. 2nd molars
tip torque rotation
upper 00
-140
10
lower 00
-100
0
Despite the additional torque, it is sometimes
necessary to add buccal root torque to the
rectangular wire in the finishing stages.
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66. Lower 2nd
molar
00
tip is used. The band and the tube are placed
parallel to the occlusal surface, as with the
upper molars, and this provides 20
mesial
crown tip for the lower 2nd
molars.
The –350
torque (Andrews) has been
unacceptable due to persistent lingual crown
torquing of these teeth.
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67. This effect may be due to
1. the eruption pattern of 2nd
molars and
anatomy of mandible in the area.
2. arch forms which show medial curvature in
this area.
3. occlusal contact with upper 2nd molar.
4. improper bracket placement.
5. combination of these factors.
Therefore, -100
torque brackets are now preferred
as resolve these problem in most cases.
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70. ANTHONY D. VIAZIS in 1995.
1st
system to use bioefficiency to minimize
iatrogenic root resorption while maximizing
efficiency.
Long axis indicator ensures accurate placement
and alignment. The elbow side extension
provide maximum tip control. Single elevated
slot reduces wire bracket contact and friction.
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71. Interslot distance (large arrows) is greater than
inter-bracket distance (small arrows). Large
interslot distance (large arrows) allows wire to
flow smoothly from bracket to bracket.
Stiffer wire between brackets (small arrows) than
in interslot space, providing greater rotation
and tip control.
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72. Philosophy
Uses new technology.
Wires and brackets – reduces the forces used to
move teeth and achieve more biocompatible
intervention with less patient discomfort.
Overcorrect malocclusions and work with largest
possible wires from the start of the treatment.
Modification of Andrews, Roth, Alexander and
Hilgers prescriptions.
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73. Places upper central incisor bracket at the
middle of the tooth (the FA point of Andrews
coincides with the slot).
Patient friendly and users friendly system –
designed to shorten the time consuming initial
phase of treatment.
Reduces burnout for both the patient and
clinician – proceeding to more quickly to
individualized finishing stage.
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74. Bracket Design
Archwire’s maximum potential achieved with
largest possible wire size.
This requires maximum interslot distance for
maximum archwire flexibility.
x – length of wire between the slots of adjacent
twin brackets, then 1.5x would be the distance
between the slots of narrow single brackets.
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75. Stiffness is 1/x3
of the length of the wire
Amount of deflection or range is x2
of the length
of the wire,
An archwire between narrow single brackets
would have 3.37 times less stiffness and 2.25
times greater activation—and thus much
greater flexibility—than an archwire between
twin brackets.
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76. Conventional single brackets have not been as
popular as twin brackets because they have
virtually no capability of controlling rotations or
tipping.
Thus, the author had developed a multifunctional
single bracket for Bioefficient Therapy that
solves this design problem while providing
optimal tooth movement.
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77. Capabilities
1. Conformity to crown anatomy and gingival
outline: useful for bicuspids, where the
brackets can be placed as far gingivally as
needed because of a narrow, rounded gingival
end.
A low profile allows the brackets to blend in
well with the archwire.
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78. • 2. Ease of use: The ball indicates toward the
center of the curvature of the gingiva, the
vertical member automatically lines up along
the long axis of the tooth.
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79. 3. Minimum friction.
4. Tip control. as archwire contacts the side
elbows, it makes the single slot into a wide twin
slot that produces root movement before any
further crown movement.
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80. 5. Rotation control. The narrow, elongated
configuration of the brackets, with the wings
moved toward the mesiodistal surfaces of the
teeth, provides maximum rotation control.
Both wings and elbows can be used for ligation.
Larger interslot distance (x1) compared to
conventional brackets (x2) allows greater wire
flexibility. Shorter interbracket distance
increases wire stiffness for rotation control.
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81. 6. Vertical slot. A vertical slot is a helpful bracket feature
even for clinicians who do not use it consistently,
because it can be used with the new nickel titanium
uprighting springs to enhance and detail tooth
movement during the finishing stage. The slot does
not add significantly to bracket width.
7. High anterior torque. It is more efficient and less time-
consuming to have torque built into the brackets than
to torque the archwires. Because most clinicians finish
with undersize wires, extra torque is needed to
counteract any tipping effect produced by active
mechanotherapy, especially during space closure.
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84. ABO reports in 1996 – common mistakes for case
reports failing phase III examination.
Shortcomings of PEA, of existing straight wire
concepts warrant improvements.
This is also considered in the 3rd
generation.
This lead to the development of Butterfly Bracket
System by Dr. S Jay Bowman and Dr. Carano in
2004 with Andrews’s original concepts.
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85. 5 reasons of Creekmore and Kunik
1. Inaccurate bracket placement,
2. Variations in tooth structure,
3. Variations in anteroposterior jaw relationships
affecting incisor position.
4. Lack of overcorrection built into treatment
mechanics and
5. Mechanical deficiencies of the orthodontic
appliance – force not applied at the centre of
resistance, play between wire and slot, or
force diminution.
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86. New low profile PEA bracket with a vertical slot.
Adds versatility to the appliance, permits
addition of varieties of auxiliaries.
This eliminates brackets with hooks.
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88. 1. The vertical slot
Simple v-slot – new treatment options and
auxiliaries.
• Reduces the potential tissue impingement,
reduces trapped food and plaque, and making
archwire tying easier.
• Usage of T pin for elastics, other auxiliaries –
rotating springs, uprighting springs and power
arms for retraction.
• Eliminates need for Kobyiashi ties of soldered
hooks.
• Blocked out or ectopically erupted tooth – steel
ligature placed through the vertical slot to sling
tie out.
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89. 2. Progressive posterior torque
Most prevalent error found by ABO Improper
bucco-lingual inclination of posterior teeth.
Common error considering the extreme amount
of mandibular posterior lingual crown torque
designed to obtain cortical anchorage.
Compounding this is the increasingly common
use of expansion treatment with a prescription
that generally features limited amount of
maxillary posteriors lingual crown torque.www.indiandentalacademy.com
90. 2. Progressive posterior torque
Increased maxillary posterior crown torque was
added to this system to reduced buccally
tipped molars while reducing posterior
mandibular torque is intended to diminish the
typical rolling-in or linguoversion of
mandibular molars.
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91. 2. Progressive posterior torque
The combined effect is an improvement in the
final bucco lingual occlusion by flattening the
curve of Wilson, minimizing posterior overjet
and reducing the prominence of palatal cusp.
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92. 2. Progressive posterior torque
Various prescriptions to overcome the
undesirable effects
Maxillary posteriors have -140
(prevent buccal
tipping of molars) whilst lower counterpart
have -10 of lingual torque.
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93. 3. Reversible 2nd
Premolar Bracket
5th
most common error in ABO – lack of occlusal
contact reason attributing were 2nd
premolars.
0 or –ve angulations
leading to improper inter-
cuspation
+ve tip of +30
improve
posterior marginal ridge
adaptation in non-
extraction. www.indiandentalacademy.com
94. 0 or +ve angulations leading
to improper inter-cuspation
Reversible 2nd
premolar
brackets with -30
tip
improves root paralleling in
extraction cases
So, in 1st
premolar extraction
cases brackets of 2nd
premolar are switched to
the contralateral sideswww.indiandentalacademy.com
95. For cases with 2nd
premolar
extraction or slipping of
anchorage is planned –
upper and lower 2nd
premolar brackets are
placed on the 1st
premolars.
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96. 4. Progressive Mandibular Anterior Tip
2nd
most common error – alignment of teeth in
particular anterior root angulation.
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97. 4. Progressive Mandibular Anterior Tip
Progressive mesial crown tip placed – reduces
distal crown tipping and root convergence of
the lower incisors.
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98. 5. Preventive Mandibular Anterior Torque
Some undesired tendency
• for maxillary and mandibular anteriors to be
tipped labially (increased instability, lip
protrusion and taxing anchorage),
• of clockwise rotation of mandibular plane
(increasing class II relationships and
decreasing stability) and
• of extrusion of maxillary incisors increasing
gingival display.
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99. 2 options of torque:
1. Preventive lingual crown torque of -50
in
mandibular anteriors of this system is
intended to resist the inherent tipping of
incisor during leveling.
2. Brackets with an optional -100
torque for use
in class II cases to reduce the labial tipping
from class II elastics or fixed functional
appliances like Jasper Jumper and Hersbt.
5. Preventive Mandibular Anterior Torque
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100. 6. Angulated 1st
Molar Attachment
Marginal ridge discrepancies between 1st
and 2nd
molars and 2nd
premolars and 1st
molars.
Reason
Difference in the heights of proximal
marginal ridges of the upper 1st
molar, standard
molar bands end up positioned too gingivally in
the distal aspect, thereby tipping the molar tube
distally.
Result
Prominence of disto-
buccal cusp of the 1st molars,
marginal ridge discrepancies
and occlusal interferences.www.indiandentalacademy.com
101. 6. Angulated 1st
Molar Attachment
60
of tip is added to the attachments on 1st
molars
to help compensate for the difference in the
mesial and distal, marginal ridge height of these
teeth.
So, these bands be fitted evenly at the mesial
and distal but the slot in the bracket will be
level.
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102. 7. Improvement in overjet
4th
most prevalent error, mostly in the posterior
teeth.
Reason
Over-expanded arch blanks combined with
bimax expansion therapy.
Result
Discrepancy in overjet in both anterior and
posteriors apart from flared molars and distally
tipped incisors
This leads to esthetic effect of wider than
normal smile. www.indiandentalacademy.com
103. Remedy
progressive posterior torque (reduced lower
and increased upper).
Prefer archform consistent with patients
pretreatment anatomical shape with
maintenance of inter canine width.
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105. Conclusion
Throughout the development of the various
bracket prescription there has been main
concentration on the Andrews 6 keys to
occlusion.
Apart from this, there have been changes in
major aspect that being tip and torque. So, it
would be wise to say based on chances of
relapse to the respective cases the desired
prescription be preferred.
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106. References
• Andrews – The six keys to normal occlusion. AJO-
DO, Volume 1972 Sep 296 – 309.
• RG Alexander - The Vari-Simplex Discipline: Part 1 -
Concept and Appliance Design. JCO, Volume 1983
Jun 380 – 392.
• Andrews LF - The straight wire appliance, origin,
controversy, commentary. JCO, 1976 Vol 10; 99 – 114.
• Anthony D. Viazis - Bioefficient Therapy JCO Volume
1995 Sep 552 – 568.
• James J. Hilgers - Bioprogressive Simplified Part 2
The Linear Dynamic System. JCO, Volume 1987 Oct
716 – 734.
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107. References
• Aldo Carano and SJ Bowman – the butterfly
system. JCO, Volume 2004 38; May 274 - 286
• Roth RH: treatment mechanics for the straight
wire applaince,
Root TL: the level anchorage system,
Graber and Swain – orthodontics current
principles and techniques, St. Louis, 1989, C V
Mosby Co.,
• Proffitt WR – contemporary Fixed
Orthodontics, in Profitt, editor contemporary
orthodontic, ed. 3, St. Louis, C V Mosby Co.
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108. References
• RH Roth - Five-Year Clinical Evaluation of the
Andrews Straight-Wire Appliance: JCO,
Volume 1976 Nov 836 – 850,
• RH Roth - The Straight-Wire Appliance -17
Years Later: JCO, Volume 1987 Sep 632 – 642,
• JC Bennett and RP Mc Laughlin - Orthodontic
management of the dentition with the
preadjusted appliance C V Mosby Co.,
• JC Bennett RP Mc Laughlin and HJ Trevisi -
Systemized orthodontic treatment mechanics C
V Mosby Co.,
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