Orthodontic alignment phase of pre-adjusted fixed appliance PART 1

Orthodontic alignment phase
of pre-adjusted fixed
appliance
PART 1
Prof dr Maher fouda
Mansoura Egypt

The former standard
edgewise appliance
employed
relatively similar brackets
on the teeth, and thereby
required the orthodontist
to place bends in the
archwire
to individually position
each tooth in terms
of their relative horizontal
‘in–out’ positions, their
crown angulation
(mesiodistal crown ‘tip’)
and
crown inclination
(buccolingual crown
‘torque’).
Edgewise bracket

This
prepared
archwire then
engaged the
brackets in an
‘edgewise’
manner,
hence the
name.

In the mid-1970s,
the American orthodontist
Lawrence F. Andrews
introduced the ‘Straight-wire
appliance’,which
modified the standard
edgewise system such that the
information for the in-out
position of each tooth, its
crown tip and crown torque
was incorporated into
the respective bracket for each
individual tooth, i.e.
the details of the final tooth
position is incorporated
in each ‘preadjusted’ bracket.
Preadjusted Siamese edgewise brackets
showing twin design and contoured
base. The bracket prescription will position
the tooth in three dimensions, generating
mesiodistal tip, torque and in/out positioning.

This was achieved
by varying the thickness of
each bracket base (for
the in-out position of the
respective tooth), and by
varying the angulation of
each bracket slot relative
to the long axis of each
tooth in the mesiodistal
plane
(for the crown angulation)
and contouring the base
of the bracket
occlusogingivally (for the
crown inclination).
Straight wire bracket

Clinicians must understand
prescriptions to achieve
ideal tooth position. Even
with pre-
adjusted appliances,
achieving all six keys of
occlusion is still difficult .
There is a need for a bracket
inventory to
include a variety of
prescriptions and the
knowledge to apply them in
different scenarios for
individual patient needs.
pre-adjusted bracket prescription
“prescription” i.e. the in out, tip and
torque values

Whilst the pre-adjusted
appliance is economical and
efficient, and
has no doubt revolutionised
orthodontic treatment, it relies
heavily on accuracy of
bracket
placement, and no single
prescription totally eliminates
wire bending. The outcome of
orthodontic treatment,
however, does not rely on the
prescription alone.
pre-adjusted bracket prescription

Therefore, when the teeth
are in their correct
three-dimensional positions,
there is a level bracket
slot line-up, i.e. the bracket
slots in each arch are at the
same height, and there are
no offset bends in the
archwire.
These preadjusted bracket
systems have reduced
the requirement for wire
bending dramatically.
the alignment stage

the bracket slot size refers to the
dimensions of the horizontal
channel within a
bracket that receives the
orthodontic archwire. The
most commonly used bracket
slot sizes are the
0.018 × 0.025-inch (0.46 × 0.64
mm) and the larger
0.022 × 0.028-inch (0.56 × 0.7
mm).
Bracket slot dimensions and
rectangular archwire
dimensions in cross-section. A
0.022 × 0.028-inch bracket slot is
shown, with a 0.019 × 0.025-inch
rectangular archwire.

The type used
is dependent on the
preference of the orthodontist,
but the 0.022 × 0.028-inch
bracket slot does allow the
use of heavier stainless steel
archwires, which make
dental arch levelling potentially
easier Bracket slot dimensions and
rectangular archwire
dimensions in cross-section. A
0.022 × 0.028-inch bracket slot is
shown, with a 0.019 × 0.025-inch
rectangular archwire.

To avoid long-winded
terms in clinical practice,
user-friendly
abbreviations may be
used at the
chair side. The 0.018 ×
0.025-inch bracket slot
size
is abbreviated and
pronounced an ‘18-slot’,
and the
0.022 × 0.028-inch bracket
slot a ‘22-slot’.

A round
archwire, e.g. a
0.018-inch stainless
steel, is pronounced
‘18-steel’, whereas a
rectangular
stainless
steel archwire with
the dimensions
0.019 × 0.025-
inch is pronounced
‘19–25 steel’.

Tipping occurs when
the crown of a tooth
moves more than its
root in a given
direction. This form of
movement is common
during
orthodontic treatment
as the moment
created by the applied
force will
tend to cause tipping..
Point contact between the
round wire and bracket

It is important
to remember
that when a
tooth tips,
the crown and
root move in
opposite
directions.
Point contact between the
round wire and bracket

Stages of Straight
Wire Technique
1. Leveling and
aligning.
2. Overbite
reduction.
3. Overjet reduction
and space closure.
4. Finishing and
occlusal detailing.
The initial leveling and aligning
can be done with a light round
arch wires, such as nickel,
titanium or braided stainless steel
arch wire as they apply gentle
forces

The flexibility of these
wires
was excellent for
individual tooth
alignment in many
clinical situations.
However, it was not
effective when
wire stiffness was
needed to retract
canines, level arches,
and close spaces.
The maxillary teeth
were bonded with fully
programmed
Preadjusted 0.022 MBT
prescription brackets .
Brackets were bonded
in the lower arch after
sufficient overjet was
achieved and the
arches were aligned
using the following
sequence of
archwires; 0.012 Niti,
0.014 Niti and 0.016
Niti.
Later, 0.018ss wire followed by 0.019 x 0.025 stainless
steel arch wire was placed to level and improve the
torque of the upper incisors
Functional Shift During Orthodontic Correction of Class
II Division 2 Malocclusion in an Adult- A Rare Case
Report Archives of Dentistry and Oral Health
Volume 1, Issue 1, 2018, PP: 22-28

During alignment
period, the nickel-
titanium alloy
group of
wires was
developed, but
orthodontists were
unsure
about when to use
them.
Initial alignment

These bends anchor
molars in a palatodistal
position and
are indicated to correct
or prevent molar
rotation as a
consequence
of intraoral or extra
oral traction.
Toe-in

They are usually
done in round
(0.018" or 0.020") or
rectangular (0.017" x
0.025") wire, making
a 200 or 30° palatine
or lingual-wise
(Toe-in) at the end of
the arch wire
(at the entrance of
the molar tube).
Toe-in

Advantages
1. They are done in
the arch wire.
2. The Toe-in bend
prevents palatomesial
molar rotation.
3. They are multipurpose
anchorage elements
because
can correct and prevent
rotations

Disadvantages
1. The patient can refer
pain at molar level when
the arch
is placed in the molar tubes
while the molars begin to
rotate.
2. It can provoke TMJ
disorders due to premature
contact points that can
appear during molar
inclination.
Recommendati
on
1. Once the
spaces are
closed we must
take the bend
off
so we can align
the molar again

Intraorally, the
patient had gingival
recession related
to the ectopically
erupted UR3 and
LR4.
case report showing the
stages of orthodontic
straight wire fixed
appliance

Patient had a full set of
permanent teeth erupted
in his mouth except for
the partially erupting
lower right permanent
canine (LR3), an
acceptable composite
filling in the LL6, and
sizeable defective filling
in the LR6.

The patient had a
Class II incisor
relationship, angle
class I molar
relationship
bilaterally. He had
Class I canine
relationship on the
left side and
undetermined canine
classification on the
right side.

The malocclusion
is complicated by
proclined and
protruded upper
and lower incisors.
He had moderate
crowding in the
upper arch and
severe crowding in
the lower arch.

Furthermore, he had 6
mm increased overjet,
shallow bite that was
around 10%, ectopic,
and buccally positioned
UR3 and LR4, partially
and ectopically erupted
LR3. The patient had
multiple rotated teeth.
The lower midline is 2
mm shifted to the right
to the upper midline

Space analysis using
digital caliber indicated
that there was moderate
crowding (3.6 mm) in
the upper arch and
severe crowding (7 mm)
in the lower arch.

Bolton analysis
revealed 2.6 mm overall
mandibular excess
(93.8%), including 0.9
mm of anterior
maxillary excess
(75.3%). Therefore, he
had 1.7 mm posterior
mandibular excess and
average curve of Spee

Panoramic x-ray shows
erupting lower right
permanent second molar
(LR7), impacted LR3,
developing upper and
lower third molars (crown
formation stage) with
future impaction tendency
of the lower right and left
third molars. The LL6 had
a composite filling. The
LR6 had poor root canal
treatment and a
comprehensive defective
coronal restoration

the patient has a
skeletal class III
relationship (SNA =
76°, SNB = 75.9°,
ANB = 0.1°) that was
confirmed by Wits
appraisal (−2.6 mm).
He had protruded
upper and lower
incisors (U1-NA =
14.5 mm), (lower
incisors to Nasion-B
point [L1-NB] = 8.3
mm), (lower incisors
to A- Pogonion
[L1-Apo] = 8.4 mm).

Extraction of all first
premolars usually
performed to manage
bimaxillary dentoalveolar
protrusion.
Regarding the status of
LR6 this tooth was
questionable, and a
decision made to extract
upper right first premolar
(UR4), upper left first
premolar (UL4), lower
left first premolar (LL4),
and LR6.

For anchorage
preparation, a
transpalatal
arch (TPA)
planned for the
upper arch, and
second molars
were included
to maximize
anchorage.

TPA cemented on the
upper first molars as
an aid to the
anchorage. Referral
of the patient to the
dental surgeon for
the extraction of the
selected teeth.
Comprehensive fixed
orthodontic treatment using a
pre-adjusted edgewise fixed
orthodontic appliance, 0.018 ×
0.025-inch Roth prescription.

Postpone bonding of the
upper and lower incisors
to avoid excessive
flaring while leveling
and alignment.
Initial leveling and
alignment of the upper
and lower teeth were
performed using a round
0.014-inch nickel-titanium
archwire (NiTi) and
canines’ laceback ,
followed by 0.016-inch
NiTi and then 0.016 ×
0.016-inch NiTi.

During the leveling and
alignment stage, placement
of buccal and lingual
buttons on the lower
right canine to derotate
it by applying a couple
of force was performed
Once the canine
derotated and aligned,
canine retraction
started on 0.016 ×
0.022-inch SS archwire
using power chain.

After canine retraction,
the upper and lower
incisors were leveled
and aligned, and then
the midline was
corrected.
were retracted using
rectangular SS 0.016
× 0.022-inch SS
archwire with T-loop
in both arches that
was activated by
cinch back the wire
every 3 weeks.

For the protraction of the
lower-left permanent
second molar (LL7), space
closure was accomplished
by using rectangular SS
0.016 × 0.022-inch SS
archwire with Omega
closing loop. After space
closure, arch coordination
performed. Then, finishing
and detailing using 0.017 ×
0.025-inch titanium
molybdenum alloy archwire
(TMA) and 0.017 ×
0.025-inch SS.

Initial Alignment
Achieving well-aligned arches is one
of the first objectives
in treatment . Eliminating rotations,
occlusogingival and buccolingual
displacements facilitate
future treatment stages.
Preliminary alignment,
whether into complete arches or
arch segments, simplifies
future adjustments and tooth
movements by
eliminating significant interbracket
discrepancies.
A major objective of initial alignment is the
creation of well-aligned and coordinated
dental arches.

Initial alignment is
usually obtained by
the use of
light, round arch
wires. Common
choices for arch
wires at this stage are
nickel/titanium alloys
or
braided steel wires.
Treatment of Class II division 2 malocclusion
with impacted
lower canine
October-December 2016 / Volume 7 / Issue 4
International Journal of Orthodontic Rehabilitation
Case report

Wire diameters frequently
range from 0.012-inch to 0.020-
inch diameter wires,
depending on severity of the
malalignment and
bracket slot size.
Nickel/titanium wires have the
further
advantage of superelasticity,
providing a constant
force on the teeth independent
of the wire deflection.
Treatment of Class II division 2 malocclusion
with impacted
lower canine
International Journal of Orthodontic Rehabilitation
Case report

Efficient clinicians avoid
reflexively or automatically
progressing through a sequence of
arch wire sizes
(i.e., arch wires should be
changed purposefully).
Specific clinical responses should
be desired when
replacing an arch wire. These
early wires should be
changed only if there is
permanent deformation of the
wire or if the wire is delivering
inadequate force levels
and treatment is progressing too
slowly.
Treatment of Class II division 2 malocclusion with impacted
lower canine
International Journal of
Orthodontic Rehabilitation

lower canine
MBT appliance 0.022 × 0.028˝
slots (Ormco, Glandora, CA,
USA) were used. Anchorage was
enhanced by transpalatal
arch placed on banded maxillary
first molars.
Alignment
and leveling in the maxilla were
accomplished with the
following sequence of arch wires:
(a) 0.016 heat-activated
nickel–titanium (NiTi) archwires, (b)
0.018 stainless steel
archwires, and (c) 0.017 × 0.025
stainless steel archwires.

lower canine
After 3 months of
alignment, 0.018 stainless
steel intrusion
arch was placed in the
upper arch to level the
maxillary central
incisors and correct deep
bite
Fifty grams of force
was used to intrude
central incisors.

lower canine
After deep overbite
correction, MBT brackets were
bonded on the mandibular
dentition. After initial alignment
and leveling, space was
opened for the lower right canine
using NiTi open coil springs
on 0.017 × 0.025 stainless steel
archwires. The impacted
canine was exposed by surgical
means, and a bondable button
was placed. Orthodontic traction
was applied after 2 weeks
of exposure, and a vertical loop
made of 0.018 stainless steel
was used to apply extrusive forces
on the canine .
October-December
2016 / Volume 7 / Issue
4

lower canine
Both the arches were coordinated
on 0.019 × 0.025
stainless steel archwires. Palatal
root torque of 11 and 21 was
incorporated in 0.021 × 0.025˝
titanium molybdenum alloy
archwires to correct torque of
upper incisors. Finishing was
accomplished on 0.021 × 0.025˝
braided stainless steel arch
wires. Gingivotomy was
performed before bracket removal
to improve the gingival contour of
11 and 21. Composite
restorations of incisor crowns
were done to achieve ideal
height-width ratio.
October-December
2016 / Volume 7 /
Issue 4

Toward the end of initial
alignment, the brackets
become well aligned on the
arch wire. At this point,
bracket placement
discrepancies become
apparent .The bracket
position errors result in
incorrect tooth positions
even though the wire rests
passively in the bracket
slots
Class III
malocclusio
n treated
by
extraction
of lower
first
premolars,
upper
second
premolars
and fixed
appliances.

Further correction of
tooth position with
round wires could be
obtained
through placing
bends in the wires to
compensate
for the faulty bracket
position or by
repositioning the
bracket.
The brackets are aligned on the wire,
but rotations of the teeth remain. A,
The lateral incisor bracket has been
placed too far distally, and the canine
bracket
has been placed too far mesially B,
Both premolar brackets are distal to
the desired position. The arrows
indicate the
approximate position for proper
bracket placement.

It is generally
more efficient to
remove and
reposition
brackets
following initial
alignment rather
than
placing bends in
the arch wires.
(a, b) Failure to seat the LR1 and LL1 brackets has
resulted in an excessive, uneven layer
of adhesive beneath each bracket base. Engagement
of a lower rectangular Nickel-Titanium archwire
highlights the rotational errors (a). A lower
rectangular Beta-Titanium archwire with first-order
correction bends is ligated to address the position of
LR1 and LL1 (b)

Bracket
discrepancies should
be identified
and corrected at this
stage by placing a
new
bracket more ideally
on the tooth. The
same light arch
wire can be used
until alignment is
attained.
A bracket positioning
error with inadvertent
reversal of the maxillary
central incisor
Roth brackets. The
intended 5 degrees of
mesial crown tip has
been converted into
distal tip leading
to a second-order issue.
This can be rectified
either with wire bending
or bracket repositioning

Initial orthodontic
alignment typically
represents the first phase
of fixed appliance-based
treatment.
In otherwords alignment is
the lining
up of teeth of an arch in
order to achieve normal con-
tact point relationships.

The objectives of this
stage include
correction of horizontal
and
rotational
discrepancies
(alignment),
improvement of gross
angulation and
inclination
issues and vertical
correction (levelling)
between adjacent
teeth.
anterior single
tooth crossbite
Elastomeric orthodontic
separators between the
canine and premolar
Instanding tooth
(central incisor) ligated
with ligature wire
Stainless steel base
archwire placed
above nickel-titanium
wire for stability

Ultimately,
this involves alignment of
the bracket slots relative
to each other permitting
progression
into larger dimension and
stiffer wires at later
treatment stages when
other objectives such as
overjet reduction and
space closure can be
achieved.
(a) Pretreatment mandibular occlusal view. (b)
Mandibular initial archwire: 0.016-inch NiTi,
interproximal enamel reduction; class 3 elastics. (c)
Mandibular finishing archwire: 0.017 × 0.025-inch SS.
(d) Threeyear posttreatment mandibular occlusal view

The first
phase in all
fixed
appliance
treatment is
to align and
level the
dentition.
Tooth alignment and
levelling
in the maxillary arch
(note the use of a
quadhelix to expand
the arch).
Tooth alignment
and
levelling in the
mandibular arch.

Levelling
means the correction of
marginal ridge
discrepancies as opposed
to definitive overbite
control.
Archwire sleeve protective tubing
Or leveling is
the process in which the
incisal edges of the
anterior teeth
and the buccal cusps of
the posterior teeth are
placed on
the same horizontal level

To achieve this,
small-diameter
flexible nickel
titanium or
multistranded steel
archwires are used
A couple being used to rotate a tooth.
multistranded steel
archwires

Wires used in this
initial phase in an
orthodontic
treatment requires
them to have low
stiffness, high
strength and long
working range.

The ideal
wires to use
in this
phase of
treatment is
a Nickel-
Titanium
archwires.
Palatal arch with
Nance button.
Transpalatal arch.

Low stiffness will allow
small forces to be
produced when the
wire is engaged in the
bracket slots of teeth.
High strength would
prevent any
permanent
deformation when the
wire is engaged in
teeth which are
severely crowded

In cases where
vertical
movements are
required, for
example with an
ectopic canine,
vertical
reinforcement of
anchorage may be
required .
Loss of vertical anchorage during the
alignment of the upper right ectopic canine.
A transpalatal arch providing additional
vertical anchorage during alignment of the
ectopic upper right canine.

This might involve
the use of a
transpalatal arch
(TPA) attached
to bands on the upper
first molars . Some
clinicians use an
upper removable
Loss of vertical anchorage during the
alignment of the upper right ectopic canine.
A transpalatal arch providing additional
vertical anchorage during alignment of the
ectopic upper right canine.
appliance, with acrylic
palatal coverage for
additional vertical
anchorage support.

Patient with severely
displaced upper right
canine. Use of continuous
superelastic wire for
leveling would have side
effect of canting occlusal
plane.
A continuous archwire system is simple to
use and relatively comfortable for the patient, but
it is statically indeterminate, since the wire is
inserted into a series of brackets.
OVERVIEW
Passive and Active Overlay
Systems
2004 JCO,
Alignment of high canines

Patient with severely
displaced upper right
canine. Use of continuous
superelastic wire for
leveling would have side
effect of canting occlusal
plane.
A continuous archwire system is simple to
use and relatively comfortable for the patient, but
it is statically indeterminate, since the wire is
inserted into a series of brackets. The forces generated
by the appliance and the forces resulting
from function and the muscular matrices are
therefore unpredictable. Although a continuous
archwire can often produce satisfactory results, it
can also generate unwanted side effects, especially
in cases with significant individual tooth malalignments
Alignment
of high
canines

A way to limit these side effects and thus
improve the effectiveness of continuous archwire
systems is to use two wires simultaneously. This
approach is commonly referred to as an “overlay
system”. A stiffer wire, called the “master”, is
used to control the archform, and a highly elastic
wire, called the “server”, to deliver the forces
needed for tooth alignment
Same patient treated with active overlay
system for sagittal and transverse expansion. Use
of .019"  .026" stainless steel master wire during
canine leveling will prevent canting of occlusal
plane.
Alignment
of high
canines

Passive Overlay Systems
Overlay systems can be categorized according
to the function of the master wire. In a passive
system, the master wire is used only for
anchorage, bypassing the teeth to be moved,
while the server (an .014" or .016" superelastic
wire) is used for corrections of
severely displaced teeth.
Alignment of
high canines

Passive overlay system
in case with sufficient
space for
alignment of upper right
lateral incisor. A. .018"
Australian master
wire keeps already
leveled teeth in place
while .016" superelastic
server wire aligns lateral
incisor. B. Continuous
archwire
inserted after lateral
incisor has been
aligned.

Passive Overlay Systems
If enough space is available for the alignment
of one or two teeth, a passive system is
appropriate. A rectangular stainless steel or round
Australian wire is used as the master wire, with
step bends bypassing the displaced teeth .

If enough space is available for the alignment
of one or two teeth, a passive system is
appropriate. A rectangular stainless steel or round
Australian wire is used as the master wire, with
step bends bypassing the displaced teeth .

The server wire is inserted into the bracket slots
on the malaligned teeth and then either tied to the
master wire, as shown by Begg and Kesling, or
inserted into the slots of the adjacent brackets,
beneath the master wire, as recommended by
Hilgers. It should be noted that if the master wire
is tied directly to the server, it will produce a Vbend
effect on the server wire.

Active Overlay Systems
In an active overlay system, the master wire
is used to deliver additional sagittal or transverse
forces, while the server wire is used for alignment.
The directions of the forces delivered by
the master wire are determined by its
configuration.
10
Alignment of class Iidiv 2

If there is insufficient space available for
the alignment of displaced teeth, the master
wire’s bypass bend should be slightly longer than
the interbracket distance between the two teeth
adjacent to the malaligned teeth .
Alignment of class II div 2

Active overlay system used to provide space for leveling proclined
upper central incisors. A. .018" Australian master wire configured with
bypass bend 1mm longer than interbracket distance. B. Continuous
archwire inserted after central incisors have been proclined.
Alignment of class II div 2

Thus ,the master wire will generate space while the
server wire brings the teeth into their correct
positions. An alternative is to place open-coil
springs on the master wire . This method
generates friction, however, and the presence of
the springs may prevent complete alignment of
the displaced teeth.
Open-coil spring
provides space for
alignment of lingually
displaced second
premolar with
.016" superelastic
server wire and .018"
Australian master
wire.
ALIGNMENT OF LINGUALLY INCLINED SECOND BICUSPID

A continuous Niti wire
placed on all the teeth
including the canine
would result in
incisor intrusion,
anterior open bite
tendency with
dumping of the
anterior and
posterior segment
towards each other,
Undesirable side effects produced by a continuous wire
placed through all the brackets.
the forces generated upon
placement of a continuous arch wire in a dentition with partially
impacted canine.

loss of arch
length, reduced
space in the
canine region and
undesirable
rotation of the
high canine will
also result . The archwire is partially
ligated to the canine

An auxiliary segmented T-loop made
from 0.022 inch MBT
0.0175 × 0.025 inch TMA wire from
26 was attached
to 23 and its mesial arm was
activated in distal, occlusal,
and palatal direction to bring the
buccally displaced right
maxillary canine in the arch.
After initial
levelling and alignment with 0.014,
0.016, and 0.018 nickel-
titanium HANT archwires, both
the arches were stabilized
with coordinated 0.018 inch
stainless steel wires. 23 was bonded

Elastic archwire
inserted into a
high canine
bracket deforms
the general arch
form and
sometimes
causes canting
of the occlusal
plane.
Canting of the
occlusal plane
Alignment of high
upper canine teeth
The appliance was mounted according
to the malocclusion. The
height of the canine bracket from one
side is different to other side with
the leveling resulting in a significant
improvement

Four examples of
mechanics used to
extrude a canine. (a) An
open coil spring between
the
lateral incisor and
premolar on 0.016-inch
stainless steel wire
maintains the space while
preventing the
adjacent teeth from
tipping
Alignment of high upper
canine teeth

.
(b) A cantilever with a
V-bend can be used
to move the canine
down. The cantilever
should be
attached to the
canine with a ligature
at only one point to
avoid unwanted
moment.
Alignment of high
upper canine teeth

(c) Reciprocal
anchorage to
level maxillary
and
mandibular
canines with
an up-and-
down elastic.
canine teeth

(d) An auxiliary
0.014 or 0.016
NiTi wire can be
used along with
a rectangular SS
main archwire to
bring the high
canine down.
Alignment of high upper canine
teeth

This 12-year-old presented
with a transposition of the
upper right canine between
the lateral and central
incisor . A transpalatal arch
was used for anchorage, and
a power arm was used to
pull the tooth distal and
keep it high in the buccal
vestibule until it passed the
root of the lateral incisor
canine teeth

Power arms inserted into
the vertical slot are used to
exert a force closer to the
center of resistance of a
tooth. They come in a short
and long size depending on
the desired place you want
to exert a force. This can be
especially useful if a
temporary anchorage device
(TAD) is placed in order to
retract an anterior segment
using maximum anchorage .
Alignment of high upper canine teeth

The diagram shows the
unfavorable rotation of
the anterior segment if
the force is directed from
the TAD to the canine.
When a power arm is
used, a more favorable
bodily movement is
possible without the
unwanted rotation of the
anterior segment.
Alignment of high upper canine teeth

The aligning archwires are
initially ligated into all the
brackets, either fully or
partially,
unless a tooth is severely
crowded and short of space.
In this case, space will need to
be created before the tooth
can be aligned. This can be
achieved by aligning the other
teeth first and then placing a
more rigid wire, such as
stainless steel.
A 0.014-in NiTi archwire is engaged
into the brackets of these se-
verely maligned upper teeth

More recently, efficiency -
based practice
with the MBT philosophy
has led to immediate
progression from the
aligning nickel titanium
wire to a 0.018 inch ×
0.025 inch rectangular
nickel - titanium wire;
thus omitting the round
steel wire stage.
MBT prescription for tip and torque
(at mid-point of facial surface)

Early progression to a
rectangular
wire helps to express
torque, which determines
the final inclination of
teeth, and also
facilitates progression
onto a 0.019 × 0.025 inch
stainless steel archwire.

A length of compressed
coil spring placed on this
archwire is then used to
create space for the
crowded
tooth . Once space has
been created, the tooth can
be aligned by placing
a lighter, more flexible
archwire as described
earlier.
Space creation with push coil on
round stainless steel archwire.

Orthodontic alignment phase of pre-adjusted fixed appliance PART 1

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Orthodontic alignment phase of pre-adjusted fixed appliance PART 1