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Orthodontics Tips
and its Secrets
DR AHMED FAWZY
drahmedfawzykamis@Hotmail.com
Dr ahmed fawzzy

Tips to increase the amount
of anchorage in the upper
and lower dental arch
Dr ahmed fawzzy

Anchorage in Orthodontics
Dr ahmed fawzzy

Lace-backs for distal movement of canines following extraction of first premolars
Dr ahmed fawzzy

Definitions
Moyers :
• Resistance to displacement.
• Active elements and resistance element
Proffit :
• Resistance to unwanted tooth movement.
Nanda :
• The amount of movement of posterior teeth (molars, premolars) to
close the extraction space in order to achieve selected treatment
goals.
Dr ahmed fawzzy

MBT :
•The tooth movements needed to achieve passive
engagement of a steel rectangular wire of. 019 / 025
dimension into a correctly placed preadjusted .022
bracket system.
Definitions
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ANCHORAGE LOSS
•It is the movement of the reaction unit or the
anchor unit instead of the teeth to be moved.
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ANCHORAGE DEMAND
Depending on anchorage loss :
1. Maximum anchorage case
2. Moderate anchorage case
3. Minimum anchorage case
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Maximum anchorage cases
• Anchorage demand is very high
Not more than ¼ th of the extraction space should be lost by forward movement of the
anchor teeth
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Moderate anchorage cases
• Anchor teeth can be permitted to move forward into ¼ th to ½ of the extraction
space.
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Minimum anchorage cases
• Anchorage demand is very low
• Anchorage or "non-critical -anchorage';where 75% of space closure is obtained
by mesial displacement of posterior teeth.
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• We elaborate this type of anchorage in the arch wire
(stops, tip back, arch wire tie back, toe-in, toe-out, in-bend, out-bend) or
• With accessory elements (retro-ligature, intermaxillary elastics, lip
bumper)
• or a combination of both
Dr ahmed fawzzy

Principles of anchorage control
There are two main aspects to anchorage control:
1. Reduction of anchorage needs during leveling and aligning.
There is a need to minimize the factors which threaten anchorage and which
produce unwanted tooth movements. This reduces the demands on anchorage.
2. Anchorage support during tooth leveling and aligning.
Where necessary, there is a need to use anchorage support, such as palatal or
lingual bars, to help to control certain teeth, or groups of teeth.
Dr ahmed fawzzy

• Anchorage control needs will differ from case to case.
• Measures to support anchorage control will not be needed in both
arches, in every case.
• Every orthodontic case will be different,and the anchorage control
needs will be determined by the position of the incisors relative to PIP,
and not by the Angle's classification
Dr ahmed fawzzy

Class 2/1 example
• At the start of treatment, the upper incisors are
normally in front of PIP, and full AlP anchorage
control will be required to restrict mesial
movement and an increase in overjet.
• Upper arch anchorage control will involve
lacebacks and bendbacks, and may require
support from a palatal bar, or Class II elastics.
Dr ahmed fawzzy

Class 2/2 example
• In these cases, it is often a treatment
requirement to allow upper and lower incisors
unrestricted mesial movement in response to
the opening archwires.
• Therefore lacebacks and bendbacks may be
dispensed with, so that anterior bracket tip
can express itself.
Bimaxillary retrusion
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Bimaxillary protrusion example
• Normally full anchorage control will be
required in both arches for this type of case,
because upper and lower incisors will be in
front of PIP at the start of treatment.
• Full anchorage control is normally appropriate
in the early stages, to ensure optimal
retraction of the anterior segments.
Dr ahmed fawzzy

Class III example
• In this example, the upper incisors are
behind PIP at the start of treatment,
• Lacebacks and bendbacks will therefore be
contraindicated in the upper arch in many
Class III cases, to allow upper incisors to
procline and to allow upper arch
development.
Dr ahmed fawzzy

Class III example
• Lower incisors will typically be in front of
PIP in a Class III case.
• The lower arch will therefore normally
require full anchorage control with
bendbacks and lacebacks, possibly
supported with a lingual arch and/or Class
III elastics.
Dr ahmed fawzzy

ANTERO-POSTERIOR ANCHORAGE
SUPPORT DURING TOOTH
LEVELlNG AND ALIGNING
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lacebacks for A/P canine control
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Bendbacks for A/P incisor control
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A/P anchorage support and control for upper molars –
the palatal bar
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A/P anchorage control of lower molars the lingual arch
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VERTICAL ANCHORAGE
CONTROL DURING TOOTH
LEVELLING AND ALIGNING
Dr ahmed fawzzy

Vertical control of the incisors
• This effect can be avoided either by not bracketing the incisors at the start of
treatment, or by not tying the archwire into the incisor bracket slots, but allowing it to
lay incisally to the brackets until the canine roots have been uprighted and moved
distally, under the control of the lacebacks.
• The incisors can then be engaged without causing unwanted extrusion.
Dr ahmed fawzzy

Vertical control of canines
• It is important to avoid early archwire engagement of high labial canines .
• So that unwanted vertical movement of lateral incisors and premolars does not
occur
Dr ahmed fawzzy

1- Use of the tip back bends in the wire arch
These bends are made in the wire
arch mesial to the tube of the molar
The bend is done round (0.020") or
rectangular (0.017x 0.025") at 45°
from the occlusal plane (toward the
gingiva), preventing the mesial
inclination of the molars and making
them more resistant to displacement.
45° tip back bend
Dr ahmed fawzzy

Once activated, the wire is going to produce intrusion of the
incisors, and the roots of the molar will mesially incline making it
more resistant to movement.
45° tip back bend
Inactive tip back bend. The arrows indicate
where the crowns and roots of the molar and
incisors will move once the wire becomes
active.
Dr ahmed fawzzy

Passive Tip back in mouth.
Active Tip back in mouth.
Dr ahmed fawzzy

This type of minimal anchorage is done in the arch wire, can be round (0.020") or
rectangular (0.017x 0.025") stainless steel.
The stops are made at the mesial portion of the molar tubes in a passive manner, this
means that the arch wire must be inside all the slots
2- Use of stops
Dr ahmed fawzzy

3- Use of arch wire tie back
The tie back is a type of minimal anchorage
made directly on the arch wire.
This is done by bending the arch 45°
gingivally at the end of the molar tube; in
order to do this it necessary to let the arch
wire 5 mm in excess from the distal end of
the molar tube
Dr ahmed fawzzy

• This can be used in the initial stage of treatment during
- Alignment and leveling with NiTi or stainless steel wires) or
- In the space closure phase for anchorage control
Dr ahmed fawzzy

4- Use of retroligatures
 The initial indication for retroligatures was to
prevent canine proclination, but we have
observed that retroligatures are the most
effective minimal anchorage for the anterior
sector.
 Retroligaturures are made with metal wire
0.010"-0.012“ diameter, laced between
braces (ligature in 8) or both between and
inside the brace (double 8 ligatures); they
can be placed over or under the arch wire,
with a needle holder
Double 8 ligature over the wire
Double 8 ligature under the wire
Dr ahmed fawzzy

5- Use of intermaxillary elastics
Maxillary-Mandibular elastic
• Class II, III and delta elastics represent minimal
anchorage that limit the protrusion of the
anterosuperior or anteroinferior segments.
• They can get upper and lower teeth closer together
and are a frequent way to obtain differential dental
movement.
Dr ahmed fawzzy

Super HeavyHeavyMediumLightInside
Diameter
6oz4oz2.7oz1.8oz3mm
1/8”
6oz4oz2.7oz1.8oz4mm
3/16”
6oz4oz2.7oz1.8oz6mm
1/4”
6oz4oz2.7oz1.8oz8mm
5/16”
6oz4oz2.7oz1.8oz10mm
3/8”
Dr ahmed fawzzy

6- Use of Nance Button
• Nance button includes a small acrylic dab the
size of a coin (about lcm diameter). It reclines
against the hard palate mucosa, at the palatine
ridges level.
• It is made out of 0.036" round stainless steel
wire with rests in the molars and on the hard
palate through the acrylic dab. This appliance
can be bonded on the molars or soldered to
the molar bands
Dr ahmed fawzzy

7- Use of Transpalatine Arch (TPA),
• It crosses the palate joining as one unit both
first molars; it is effective as a moderate
anchorage appliance forming an anchorage
unit that resists mesial molar movement and
mesial rotational lingual root tendency.
• It is one of the most simple moderate
anchorage appliances to make and the most
used by the majority of orthodontists
Dr ahmed fawzzy

• We must take an impression with
bands adapted on the first upper
molars in order to fabricate one, then
we pour plaster in the impression with
the bands placed in it.
• Then we can proceed to bend the
0.036" stainless steel wire and form the
trans palatine arch, leaving a 1 or 2 mm
separation between the wire and the
palatine mucosa.
The transpalatine arch must be separated 1 or 2 mm from
the palatine mucosa in order to avoid its impingement.
Dr ahmed fawzzy

Fixed transpalatine arch soldered on the band of
the first upper molars.
Dr ahmed fawzzy

Fixed trans palatine arch bonded on the
palatine aspect of the first upper molars.
Dr ahmed fawzzy

Double trans palatine arch with palatine plate.
Dr ahmed fawzzy

Direct adhesion TPA used as anchorage at
premolar level while distalizing upper molars.
Dr ahmed fawzzy

Lesion in the dorsum of the tounge caused by
the transpalatine arch.
Dr ahmed fawzzy

8- Use of Lingual Arch
• The lingual arch is a moderate
anchorage appliance that is
widely used for dental arch length
maintenance; it is relatively rigid
and diminishes mesial molar
movement
Dr ahmed fawzzy

• The lingual arch is made from 0.036"
stainless steel round wire and it extends
from molar to molar near the lingual
aspect of the inferior teeth.
• If it is used as a leeway space maintainer,
it must rest near the cingulum of the
inferior teeth
Dr ahmed fawzzy

• If used as anchorage for the
retraction of the anterior segment,
then it must be separated 3 or 4 mm
from the cingulum.
Dr ahmed fawzzy

• The omegas of the lingual arch must be
placed away from the oral mucosa so
they do not impinge into the mucosa.
• If this happens, we must remove it for
at least a week to let the mucosa heal.
Dr ahmed fawzzy

• The lingual arch can be made according to the case at hand.
Lingual arch made from molar to premolar in order
to pull the second molar to the extraction site.
Dr ahmed fawzzy

9- Absolute Anchorage
Miniscrews
Temporary Anchorage Devices
(TADs)
Dr ahmed fawzzy

Unitek™ TAD features a
4 mm tapered body shape
and, because it is a self-tapping system,
its insertion is easier as there is no need for heavy
force application.
Dr ahmed fawzzy

A periapical radiograph should be at hand to check
root positioning and the amount of interradicular
space available for insertion of the miniscrew
Dr ahmed fawzzy

• Use infiltration anesthesia
• The amount of infiltrative anesthetic
used should be approximately 1/16
of the anesthetic cartridge
Dr ahmed fawzzy

Identify the site of the insertion of the
miniscrew using a graduated probe ,
guided by the periapical radiograph.
Dr ahmed fawzzy

. Make a punch incision in the keratinized gingiva with a gingival punch.
Dr ahmed fawzzy

• In the maxilla, the miniscrew should be inserted perpendicular to the alveolar
bone
Dr ahmed fawzzy

Check the stability of the miniscrew with a probe.
It should be firm, that is, with no signs of mobility
Dr ahmed fawzzy

Take a periapical radiograph after insertion to confirm the miniscrew position
Dr ahmed fawzzy

Tips For Space Closure
Tips For Space Closure
Dr ahmed fawzzy

METHODS OF CANINE RETRACTION IN SLIDING MECHANICS
• There are two ways in which anterior teeth are retracted.
1. By retracting the canine first followed by retraction of other four
anteriors enmasse.
2. Enmasse retraction of six anterior teeth.
Dr ahmed fawzzy

Separate canine and anterior retraction
Dr ahmed fawzzy

En-mass retraction
Dr ahmed fawzzy

METHODS OF SPACE CLOSURE
1. Elastic chains
2. Coils
3. Closing loop archwires
4. Sliding mechanics with heavy forces
5. Sliding mechanics with light continuous forces (Recommended).
Dr ahmed fawzzy

Closed chain Short chain
Elastic chains
Long chain
Dr ahmed fawzzy

Elastic chain
• Elastic chain is not recommended for closure of large spaces, because of
force level issues.
• For example, chains stretched from first molar to first molar, initially generate
400 gm of force in the upper arch and 350 gm of force in the lower arch.
• In a first premolar extraction case, for example,
Dr ahmed fawzzy

• Over-stretched chain links in the extraction sites will cause rotation
of adjacent teeth.
Dr ahmed fawzzy

• Under-stretched chain links in the extraction sites will not produce any
space closure
Dr ahmed fawzzy

• Elastic chain is useful for dealing with one or two minor
spaces towards the end of treatment and light chain can be
helpful in preventing spaces from opening late in the
treatment, when finishing .014 wires are in place
Dr ahmed fawzzy

Space closure with parallel forces
• This is done with two simultaneous forces (buccal and lingual).
• We must place additional buttons, in order to apply a simultaneous force in the
lingual aspect of the tooth as well as on the buccal side.
Canine retraction with parallel chains. Two weeks after
Dr ahmed fawzzy

Space closure with power arms
• Power arms are simple appliances that are easy to use, and are generally used for canine
retraction and anterior diastema closure.
• The biomechanics consists in getting these arms as close as possible to the center of resistance so
that rapid and stable space closure takes place (bodily movement).
• They are bonded on the gingival area of the dental crown and the force is applied through a power
chain, an open coil or a 6 ounce elastic
Dr ahmed fawzzy

Diastema closure with power arms.
After three months.
After two months.
Dr ahmed fawzzy

Space Closure with intermaxillary elastics
Rebound in the premolar zone.
Dr ahmed fawzzy

• This problem can be corrected with a thermoplastic retainer (mouth guard) in
combination with intra-maxillary elastics.
• The guard is sectioned at the extraction site level; then buttons are bonded for the
use of space closure elastics.
Dr ahmed fawzzy

• In cases that present rebound at the anterior sector due to dental proclination, we will observe
diastemas on the upper or lower incisors.
• These spaces can be eliminated with a Hawley or circumferential retainer.
• A modification of the circumferential retainer would be cutting the buccal arch and placing an elastic
as a substitute.
Dr ahmed fawzzy

CLOSED COIL SPRINGS
• The closed coils in the market, with one
and two stainless steel eyelets.
• The eyelets are soldered to the coil with
a laser and this makes placement on
tubes and brace hooks easier.
• They are comfortable to wear because
there are no sharp edges that may
lacerate the oral mucosa.
Dr ahmed fawzzy

• The length of inactive closed coil is 3 mm (this
measure does not include the eyelets) and can be
stretched up to 15 mm without deformation or
force change.
• The forces range from 25 g to 300 g depending on
the manufacturer.
3 force levels:
1- Soft (100 g, yellow eyelet)
2- Medium (150g, blue eyelet) and
3- Heavy (200g, red eyelet)
150 g closed coil.
Dr ahmed fawzzy

Closing loop archwires
Dr ahmed fawzzy

Passive "T" loop Active "T"" loop.
Passive Loop.. Active Loop.Passive closed vertical loop Active vertical closed loop.
Dr ahmed fawzzy

Passive Loop.. Active Loop.
Dr ahmed fawzzy

Disadvantages to this method of space closure.
• A lot of wire bending time was needed, and the forces were heavy;
• sliding mechanics were poor, and the mechanism had only a short
range of activation.
• Closing loop archwires are therefore not recommended for routine
space closure with preadjusted brackets.
Dr ahmed fawzzy

Sliding mechanics with heavy (ex-edgewise) forces
• In the early days with the preadjusted bracket system. Attempts were made to apply
traditional edgewise force levels (500-600 gm) to the new brackets.
• It was found that heavy space closure forces caused unwanted tip, rotation, and
torque changes
Dr ahmed fawzzy

Sliding mechanics with light forces
• In 1990, a method of controlled space closure was described using sliding
mechanics.
• This has proved effective and reliable for many years, and has seen
widespread acceptance by clinicians.
• MBT recommend the following technique
Dr ahmed fawzzy

Archwires.
• Rectangular 019/025 steel wires ('working
wires') are recommended with the .022
slot, because this size of wire gives good
overbite control while allowing free sliding
through the buccal segments.
Thinner wires tend to give less overbite and
torque control.
Dr ahmed fawzzy

Soldered hooks
• The prefer 0.7 soldered brass
hooks. Soft stainless steel 0.6
soldered hooks can be a useful
alternative, and some adult
patients prefer the appearance of
these.
• The most common hook positions
are 36 mm or 38 mm (upper) and
26 mm (lower), measured along
the line of the arch
Dr ahmed fawzzy

MBT arches with brass hooks.
The brass hook is bended to facilitate
elastic and ligature insertion.
Dr ahmed fawzzy

Passive tiebacks.
• Before starting space closure, it is recommended that the rectangular steel .019/.025 wires
be left in place for at least 1 month with passive tiebacks
• This allows time for torque changes to occur on individual teeth and for final leveling of the
arches, so that sliding mechanics can proceed smoothly when active tiebacks are placed.
Dr ahmed fawzzy

Active tiebacks using elastomeric modules.
• In daily clinical practice, these are simple, economical, and reliable.,
• Placement is not difficult and can be delegated routinely, with few complications.
• Active tiebacks using elastomeric modules are preferred for space closure in most
cases, eve though nickel-titanium springs have been shown to be more reliable and
effective.
Passive ligature. Active ligature.
Dr ahmed fawzzy

Force levels.
• Elastic tiebacks were originally described using an elastomeric module,
of the type used to hold archwires on to brackets, stretched to twice its
normal size.
• This was found to give a force of 50-100 gm, if the module was pre-
stretched before use.
• If used direct from the manufacturer, without pre-stretching, the force
may be 200-300 gm greater.
Dr ahmed fawzzy

Trampoline effect
• Clinical experience has shown that space closure can continue for
several months in patients who have failed to present for normal
adjustments, even when the elastomeric module is in poor condition
and apparently delivering very little force.
• How can this consistent clinical experience be explained? One can
speculate that there may be a 'trampoline effect' which occurs during
mastication, and which can result in an intermittent pumping activation.
Dr ahmed fawzzy

Type one active tieback (distal module).
• The .019/025 rectangular steel archwire is placed, with modules or wire ligatures on
all brackets .
• The elastomeric module is attached to the first or second molar hook. A .010
ligature is used, with one arm beneath the archwire. This makes the active tieback
more stable, and helps to keep the ligature wire away from the gingival tissues.
Dr ahmed fawzzy

Type two active tieback (mesial module).
• This follows the same principle as the type one, but the elastomeric module is
attached to the soldered hook on the archwire.
• A .010 wire ligature is attached to the first or second molar hook with several twists in
the wire, and then attached to an elastomeric module on the archwire hook.
Dr ahmed fawzzy

• With the type one and type two tiebacks, the elastomeric modules are normally
stretched to twice their resting size for activation.
• If oral hygiene is good, adjustment visits may be less frequent; they may be re-
activated after 4 to 6 weeks, and remain in place for two visits.
• If oral hygiene is poor, the elastomeric modules may deteriorate and require
replacement at every visit.
• In some cases, in the final stages of space closure, it may be helpful to use two
modules, or to augment the tieback with a 10- or 12-link elastomeric chain from
molar to molar.
Dr ahmed fawzzy

Active tiebacks using a nickel-titanium coil spring.
• Nickel-titanium springs can be used,
instead of elastomeric modules, if large
spaces need to be closed, or if there are
infrequent adjustment opportunities
Dr ahmed fawzzy

• It suggests the use of light closed coil nickel-titanium springs (344-150
and 346-150 3M Unitek) to give a force of 150 gm.
• Springs should not be expanded beyond the manufacturers
recommendations (22 mm for the 9 mm springs, and 36 mm for the
12mm springs ).
Dr ahmed fawzzy

Elastics vs Coil springs
Dr ahmed fawzzy

Elastics vs Coil springs
Coil springs
• More consistent space closure
• Rapid space closure
• Force decay occurs to a lesser extent
• Minimally affected by temperature and
other environmental factors
• Elastics
• Easy to use
• Economical
• Work well in most clinical situations
• Rapid force decay rate
• Affected by oral environment
Dr ahmed fawzzy

Tie backs vs NiTi coil-springs
• Rate of space closure
• NiTi closed coil springs- significantly greater,
- more consistent
Dr ahmed fawzzy

Obstacles to space closure
• In almost all cases, space closure is easy and proceeds
• uneventfully. Only rarely are problems encountered.
• If it appears that space is not closing as it should (about 1mm per month typically),
the spaces should be carefully measured at successive visits.
• If they are not reducing, or if wire is not appearing gradually from the distal of the
molar tube, then possible obstacles should be evaluated before resorting to
different mechanics:
Dr ahmed fawzzy

Obstacles to space closure
• Inadequate leveling.
• The working rectangular wires need to be in place for at least 1 month with passive
ties to ensure proper leveling and freedom from posterior torque pressure.
• Also, it is important not to attempt overbite correction
using reverse curve in the lower archwire at the same time
as attempting space closure.
• Overbite control should be achieved before space closure.
Dr ahmed fawzzy

Damaged brackets.
• Lower first molar brackets can be damaged and partly closed down by
excessive biting forces.
• As a short-term measure, the wire may be thinned in that area, but it is
better to replace the molar attachment.
Dr ahmed fawzzy

Incorrect force levels
• Forces above the recommended levels can
cause tipping and friction, and thus prevent
space closure.
• Inadequate force may sometimes be a cause
of slow- or non-space closure in adult
treatment.
• Force levels need to be in balance with
archwire size and stiffness.
• If they are not in balance, archwire deflection
and unwanted friction can occur. It has been
shown that archwire deflection causes friction
Dr ahmed fawzzy

Interference from opposing teeth
• This can prevent lower space closure, and it is necessary to carefully check the occlusion.
Dr ahmed fawzzy

Soft tissue resistance.
• Gingival overgrowth in the extraction sites can
prevent space closure, and can cause space to
re-open after appliance removal
• It can also be a problem when closing an upper
midline diastema. & Care is needed to maintain
good oral hygiene and avoid too rapid space
closure, as these can contribute to local
gingival overgrowth.
• In a few cases, local surgery to soft tissue may
be indicated.
Dr ahmed fawzzy

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