Newer wires /certified fixed orthodontic courses by Indian dental academy

NEWER ORTHODONTIC WIRES
INDIAN DENTAL ACADEMY
Leader in continuing dental education
www.indiandentalacademy.com


INTRODUCTION
Orthodontic wires which generate the biomechanical
forces communicated through brackets for tooth
movement are central to the practice of the profession.
In the rational selection of wires for a particular
treatment the orthodontist should consider a variety of
factors.
The characteristics desirable in an orthodontic wire
are:
 Large spring back
 Low stiffness



High stored energy



Good formability



Bio compatibility & environmental stability



Low surface friction



Capability to be welded or soldered to auxiliaries


Currently orthodontists principally use wires of 4
major base metal alloy types:
•
•
•
•

stainless steel
cobalt – chromium – nickel
nickel – titanium
beta – titanium
Each of the 4 popular base metal wires has distinct
advantages and disadvantages as summarized in the
table:


PROPERTY

STAINLESS
STEEL

Co – Cr - Ni

TMA

Ni - Ti

Cost

Low

Low

high

Force
delivery

High

High

intermediate

light

Spring back

Low

Low

Intermediate

High

Excellent

Excellent

Poor

Formability
Ease of
joining

Excellent
Soldered, welded
joints - reinforced

Soldered, welded
joints - reinforced

True weldability

high

Can’t be
Soldered or
welded

Arch wire –
bracket friction

Lower

Lower

Higher

Higher

Concern about
Bio compatibility

Some

Some

None

some

Source: William A. Brantley, Theodore Eliades
“Orthodontic materials”

COPPER NiTi
Source: William A. Brantley, Theodore Eliades
“Orthodontic materials”

• Rohit l sachdeva developed a new type of NiTi with the

addition of copper and chromium to nickel and titanium.these
copper NiTi wires were superior to other niti wires by
exhibiting decreased hysteresis and more constant forces were
produced.
• The addition of copper was to increase strength,decrease

hysteresis and to enhance the thermal reactive properties of
nickel titanium alloys.


Due to decreased mechanical hysteresis in this wire it makes it
easier to insert larger rectangular wires without patient discomfort.

The addition of copper has enabled in the development of
new quaternary alloy with four constant transformation
temperatures for four distinct force levels thus enabling
the clinician to select arch wires on a case specific basis.


They are classified as:
• Type 1 (at 15 degree c)

- generate very high forces.
- very few clinical indications.
• Type 2 (at 27 degree c)

- generates highest forces of the four types and is best
used in patients with healthy periodontium.
- when rapid tooth movement is required.


Type 3 (at 35 degree c)
- Generates force in the mid range and is best used in
patients who have a low to normal pain threshold
- patients with normal to slightly compromised
periodontium
- Relatively low forces are desired


Type 4 (at 40 degree c)
- Generate tooth driving forces when the
mouth temperature exceeds 40 degree c.

- These forces are intermittent in nature.

- Best used in patients who are sensitive
to pain,compromised periodontal condition.

- This variant would provide activation
only after consuming hot food and beverages

BETA TITANIUM ( TMA)
Source: Burstone, AJO-DO:1980 feb

The beta titanium wire has a unique balance of
low stiffness
high spring back
Formability
Weldability

COMPOSITION

•Molybdenum - 11.3%

•Tin - 4.3%

•Zirconium - 6.6%

•Titanium - 77.8%


CLINICAL APPLICATION
As a finishing wire because:
1. It delivers force values less than half that of stainless steel.these
properties make it possible to use larger rectangular wires to fill
up the slot,for earlier or more complete torque control,while
maintaining load deflection rate.
2. Its excellent elastic range and resiliency equate to increased
efficiency of activation.
.


3. It can be perfectly shaped to patients arch form

TMA’s extended plastic range makes it highly
formable,readily bent for loops and compensating
bends
It is used in the fabrication of utility arches
TMA’s moderate forces create less trauma to the
patients

DISADVANTAGE
•High coefficient of friction:

Therefore it is disadvantageous in sliding mechanics.


COLOURED TMA
Source: JCO; July 1995:Vol 29:no:7

 In the case of TMA the friction is probably due

to its relative softness compared to the harder
stainless steel bracket.
 Surface treatment can increase the hardness

and reduce the coefficient of friction.


ION IMPLANTATION

It is the process by which various elements are

ionized and accelerated towards an arch wire in a
vacuum chamber.
Gas ions (nitrogen and oxygen)are simultaneously

extracted from a plasma and accelerated in the
growing physical vapour deposition film.


 The ions penetrate the surface of wires on

impact,building up a structure that consists of both
he original wire and a layer of tin compounds(TiN
and TiO) on the surface of immediate sub surface.
 This layer is extremely hard and creates a

considerable amount of compressive forces in the
material.


ADVANTAGES
Compressive forces and increased surface hardness

improve the fatigue resistance and reduce the coefficient
of friction of the wire.

Does not alter the wire dimension thus it allows the

production of high quality wires.

Ion implantation can take place at relatively low

temperatures from sub zero to 700 degree c which allows
improvement of surface characteristics without
degradation of mechanical properties.


 Through an exclusive spi- spectrum ion beam implantation process

ORMCO has introduced TMA colours.

Colored wires produced by varying ion type
and thickness.


 Colours available are Afran,Violet,Purple and

Honeydew.

 TMA colour gives patients some exciting new

looks while at the same time providing with
many clinical benefits of TMA wire.

 This ensures a colour fastness not available in

coated wire products.


Alpha titanium
 Introduced by Mollenhauer in 1988

The alpha titanium alloy is attained by adding 6%
aluminium and 4% vanadium to titanium.
Because of its hexagonal lattice it possess fewer
slip planes making it less ductile than TMA.
Slip planes are the planes of atoms in a crystal
that can glide past one another during permanent
deformation.
The more the slip planes the easier it is to
deform the material.

Alpha titanium gets hardened by absorbing intra oral
free hydrogen ions which turn it into titanium hydride
at oral temperature of 37 degree c and 100% humidity.
Mollenhauer reported that after 6 weeks in oral
cavity,the wire becomes become brittle to bend,
Therefore any modification if required should be done
within 6 weeks.


Presently wire is available as a combination.The
anterior section is .018x.025 rectangular for torque
control while posterior section which is oval tapering
from .018 to .017.
Hence it can be used as a closing wire.


TIMOLIUM
Source: European Journal of Orthodontics; Vol 26: 2004

Timolium wire is intermediary in properties
between beta titanium and stainless steel wires
and useful in clinical situations where a
modulus of elasticity between that of beta
titanium and stainless steel is needed.
Delivers a more constant force over a long
period than stainless steel.


TITANIUM NIOBIUM/FA WIRE
 Introduced

by Rohit sachdeva in
1996.Patented by ORMCO labs.

Titanium niobium is an innovative new

arch wire designed for precision tooth to
tooth finishing.

The unique metallurgical properties of

FA(finishing arch) make it the most precise
intraoral detailing option available today.

At 80% of the stiffness of TMA,it is perfect for holding
bends yet right enough not to oversize the arch
relationship.
It possess a resiliency equal to that of stainless steel.
Available in rectangular cross sections of:
.016 x .022
.017 x .025
.019 x .025
.021 x .025


COMBINATION WIRES
DUAL FLEX ARCH WIRES/WONDER WIRES
Introduced by James l. Cannon in 1984.
Two alloys,stainless steel and nickel titanium wires
are joined by Casthook joint,just mesial to the
cuspids.


Currently a stainless steel combination wire is
also available which consists of an anterior
rectangular wire and a posterior round wire.the
rectangular wire gives better torque control.

These wires are also known as dual flex wires or
wonder wires.


DUAL FLEX 1
Titanol is a niti alloy manufactured by lancer pacific
0.016 stainless steel posterior segments and 0.016
titanol anterior segments.
Advantages:
- better molar control by stiffer posterior segments.
-alignment could be done with resilient anterior
segments.


Clinical use:

-used in phase 1 of treatment.

-any application including combination
anchorage.

-in lingual orthodontics where inter-bracket span
is minimal.


DUAL FLEX 2
0.018 stainless steel posterior segment and 0.016 0.022
titanol anterior segment as braking mechanics ( to loose
anchorage by increasing the resistance at anterior
segment )

DUAL FLEX 3
0.017 0.025 titanol anterior segment and 0.018 0.018
stainless steel posterior segment.

TANDEN WIRES
• It is an alfa titanium wire introduced by A.J

Wilcock which has rectangular cross section in
anterior segment and ovoid cross section in
posterior segment.


COMPOSITE WIRE
Source: Eur Jou of Ortho;22:2000

The new orthodontic materials of recent years have
been adopted from those used in aerospace technology.
The high performance aircraft of the 1970’s and 1980’s
were titanium based,but the current generation are
built of composite plastics,and there is every reason to
believe that orthodontic wires of this type will move
into clinical use in future.


It is interesting that one nonmetallic wire already has
been offered for clinical use.

OPTIFLEX
Source: JCO;Vol.26:Apr 1992

It is a new orthodontic arch wire designed by
Dr.M.F.Talass and manufactured by Ormco.
It has got unique mechanical properties with a highly
esthetic appearance.
It is made up of clear optical fiber,it comprises of three
layers.

A - A silicon dioxide core that provides the force for
moving teeth.
B - A silicon resin middle layer that protects the core from
moisture and adds strength.
C - A stain resistant nylon outer layer that prevents
damage to the wire and further increase its strength.


Optiflex possesses following advantages which make it
a unique archwire in terms of esthetics and mechanics
alike:
 Optiflex is the most esthetic orthodontic arch wire to

date.
 It is completely stain resistant.
 Beyond esthetics,optiflex is very effective in moving

teeth using light continuous forces.


It is very flexible.has an extremely wide range of action.
It can be tied with elastomeric ligatures to severely

malaligned teeth without the fear of fracturing the
archwire


Disadvantages
Metal ligatures can fracture the glass core.
Sharp bends should never be attempted with
OPTIFLEX.These bends will immediately fracture the
core.
Instruments with sharp edges like the scalers,directors
etc to force the wire into the bracket slot should not be
used.


Clinical applications
Adult patients who wish that their braces not
be really visible for reasons related to personal
concerns or professional conditions.
Can be used as an initial wire in cases with
moderate amounts of crowding in one or both
arches.


It should be used in cases to be treated without bicuspid
extraction.it is not the ideal arch wire for major cuspid
retraction due to its limited ability to control the distal
tipping and the labio-lingual rotation of the retracted
cuspids.


FRP ESTHETIC ORTHODONTIC WIRE
Source: Journal of Biomaterials;Aug:1997

To realize the esthetic transparent orthodontic wire the
FRP(fiber reinforced polymer) wires of the diameter
0.5 mm with the multiple fibre structure has been
fabricated by either drawing of fibre-polymer complex
at 250 c or photo polymerization method.
Biocompatible CaO-P2O5-SiO2-Al2O3(CPSA) glass
fibers of 8-20microns in diameter are oriented
unidirectionall to the longitudinal direction in polymer
matrix of PMMA or bis-GMA.

The improvement has been done to obtain the
adequate flexural strength and higher torque.
FRP wire shows the sufficient flexural strength
and a very good elastic recovery.


This FRP wire can cover the range of the
strength corresponding to the conventional
metal orthodontic wires from NiTi used in the
in the initial stage of orthodontic treatments to
Co-Cr used in the last stage by changing the
volume ratio of glass fibres with the same
external diameter
FRP wire can satisfy both mechanical
properties and estheticity which is not possible
for the conventional metal wire.


Coated composite wires
Source: Angle Orthodontist;Vol 70:2000

An investigation of the frictional properties of
composite wires against orthodontic brackets showed
that reinforcement fibers were abrasively worn from
wire faces.
This potential release of glass fibers in the oral cavity
was considered unacceptable and a surface coating
material was suggested as a potential alternative.


Prerequisites of coating material
Easily applicable in thin layers
Be wear resistant
Should have low frictional characteristics
Should be biocompatible and transparent
One material that exhibits all of these properties was
poly (chloro-p-xylylene).


The friction and wear characteristics were evaluated
and the coatings were regarded as an improvement to
the clinical acceptability of composite orthodontic
arch wires.


Esthetic wires
MARSENOL
Source:JCO,1989
Marsenol is a tooth coloured nickel titanium wire
manufactured by GLENROE technologies.
It is an ETE ( Elastomeric polytetra florethylene emulson)
coated nickel titanium.
Marsenol exhibits all the same working characteristics of
an uncoated superelastic nickel titanium wire.

The coating adheres to the wire and remains flexible.
The wire delivers constant force over long periods of
activation and is fracture resistant.


LEE WHITE WIRE
SOURCE:JCO,1988

Manufactured by LEE pharmaceuticals.
It is a resilient stainless steel or nickel titanium wire
bonded to a tooth colour ed epoxy coating.
Suitable for use with ceramic brackets.
The epoxy is completely opaque and does not
chip,peel,strain or discolour.

IMAGINATION WIRE
Introduced by GASTENKO in sweden.
It is a tooth coloured epoxy coated archwire with a
stainless steel or NiTi core.
Offers superior esthetics,hypoallergic,reduces friction
when used with Image brackets.
Round,rectangular and square wires are available.

Super cable
Source: JCO,Apr 1998

In 1993,Hanson combined the mechanical
advantages of multi-stranded cables with the
material properties of super elastic wires to create
a super elastic nickel titanium coaxial wire.
This wire called super cable comprises seven
individual strands that are woven together in a
long,gentle spiral to maximize flexibility and
minimize force delivery.

Clinical use of supercable
The most clinicallysignificant finding was that
the .016 and .018 supercable wires were the
only ones that tested at less than 100g of
unloading force over a deflection range of 1-3
mm.
Supercable thus demonstrates optimum
orthodontic forces for the periodontium.


It offers the clinician the advantage of engaging
a relatively large archwire at the start of
treatment.

By occupying more of the bracket slot,the .018
supercable is able to accomplish a greater degree
of uprighting,leveling,and rotational control than
other initial arch wires.


Supercable’s unique construction and super elastic
properties permit it to be gently engaged in even the
most crowded cases without patient discomfort.

A. Placement of initial mandibular .016" Supercable archwire.
B. Segmented .016" Supercable wire, seated in auxiliary slot of
maxillary lateral and first bicuspid brackets, is flexible enough to
be fully engaged in main arch wire slot of palatally displaced
cuspid.

Advantages
A light continuous level of force,preventing any
adverse response of the supporting
periodontium.
Minimal patient discomfort after initial arch
wire placement.
Fewer patient visits,due to to longer arch wire
activation.
Flexibility and ease of engagement regardless
of crowding.

Disadvantages

Tendency of wire ends to fray if not cut with sharp
instruments.
Tendency of arch wires to break and unravel in
extraction spaces or long unsupported spans unless
reinforced by .030 stainless steel or plastic tubing.
Inability to accommodate bends,steps or helices.


Teflon coated ligatures
Source: Angle Orthodontist; No 1:1995

Ligatures commonly used in orthodontics are either
heat treated stainless steel or Elastomeric rings.the
friction arising from a ligature depends upon its
coefficient of friction and the forces it exerts on the
bracket and arch wire.
Both clear elastomerics and teflon coated stainless steel
ligatures are esthetically appropriate for use with
ceramic brackets.
Since teflon has a low coefficient of friction,they may
invoke lower forces of friction than either elastomeric
or uncoated steel ligatures.

Static frictional resistances were observed for various
combinations of brackets,arch wires,and ligatures at
four different bracket-archwire angulations.
Overall lower friction was demonstrated with Teflon
coated stainless steel brackets when compared with
ceramic brackets.
Use of the esthetically acceptable Teflon coated ligature
as an alternative to the clear Elastomeric ligature
appears to partly reduce the high frictional resistance
of ceramic brackets.


Stress relaxing composite ligature wires.
Source: Angle Orthodontist, Vol 69;1999

Currently, Elastomeric components provide some
consistency and predictability in force application.
But the Elastomeric components assimilate odors and
colours and they experience load reductions over time.
While these characteristics are predominantly
undesirable,the load reduction feature may be useful in
certain applications.

A unidirectional fiber reinforced composite is one
option for a ligating device.
Such a composite ligature would be composed of a high
strength, flexible polymeric fiber encased in a
chemically different polymeric matrix.
A stress relaxing composite ligature was developed that
has both mechanical and esthetic characteristics.
The neutrally colored polymer-polymer composite was
created by encasing ultra high molecular weight
poly( ethylene) fibers in a poly(n-butyl
methacrylate)polymer,which was formulated from a
polysol and an optimal benzoin ethyl-ether
concentration.

The resulting composite ligature exhibited a tensile
strength more than twice that of dead-soft stainless
steel ligature,and a stress relaxing decay significantly
greater than stainless steel ligature.
With these characteristics ,the material could be used
as an orthodontic ligature when tooth movement with
negligible friction due to ligation is desired.
The featured composite could also exhibit a stress
relaxation phenomenon in which the applied load
decayed in minutes to a small fraction of its initial
value.

This characteristic could be important to practioners in
general and to residents and novice orthodontists in
particular,who potentially use excessive force to ligate
an arch wire into a bracket.
A stress relaxing composite ligature could help some
practioners achieve bodily tooth movement when
tipping might otherwise occur with the use of an
improperly adjusted stainless steel ligature.


Organic polymer wire for esthetic maxillary
retainers
Source: JCO;Vol 30:May 1996

Patients who have worn esthetic ceramic or plastic
brackets during orthodontic treatment are likely to
want esthetic retainers after treatment.
Organic polymers are used in many orthodontic
materials today because of their esthetic qualities.


Disadvantages
organic polymers wires generally have low elasticity
and thus they are easily deformed and do not exert
sufficient force for tooth movement and retraction.
If the wires are made with a high modulus of
elasticity,they become brittle.
Organic polymers also discolour because of their
tendency to absorb liquids.


MIEKO WATANABE,SHUNSUKE
NAKATA,TADASH MORISHITA developed an
organic polymer maxillary retainer wire(QCM) made
from 1.6 mm diameter,round polyethylene
terephthalate.
This material can be bent with a plier, but will return
to its original shape unless it is heat treated for a few
seconds at a temperature less than 230o c(melting point)
In prefabricating the QCM retainer wires,the anterior
portion of the wire and the wave portion are heat
treated at about 150oc immediately after bending.


Maxillary retainer with QCM organic
polymer wire.

Prefabricated QCM retainer wires.
A. Anterior portion.
B. Wave.
C. Posterior portion.

The QCM wire is thicker than traditional retainers
which can make it impossible to use on terminal molars
that have not fully erupted or are out of occlusion at the
end of treatment. In such cases it is advantageous to join
metal posterior segments to QCM wire.
QCM retainer wire showed a modulus of elasticity
similar to that of the
flat bow retainer wire. After heat treatment it displayed
littlede formation.


The shrinkage that occurs with heating allows the wire
to fit more snugly to the caste and the reduction in the
overall length can be compensated by extending the
waves.
No significant dis-colouration of the QCM wire was
noted indicating that it doesn’t absorb liquids.This
adds to the esthetic quality of the retainer.


CONCLUSION
In current day practice, patients opt for esthetics. From
the view point of esthetics, practitioners assert that
esthetics are desirable but that function is paramount.
At present, an area of potential interest is the use of
true shape memory polymers for orthodontic wires.
Many studies and researches are underway for the
development of new non metallic orthodontic wires
with improved mechanical properties as well as
esthetics.


Newer wires /certified fixed orthodontic courses by Indian dental academy

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