orthodontics

1. GOOD MORNING

2. STAINLESS STEEL &
ORTHODONTIC WIRES
DR. SUNANDA PAUL
DEPT OF ORTHODONTICS & DENTOFACIAL ORTHOPAEDICS

3. STAINLESS STEEL
• HISTORY
• TERMINOLOGY
• STEEL
• CLASSIFICATION
• STRUCTURE
• PHASE TRANSFORMATION IN STEEL
• SUMMARY OF PROPERTIES
• DUPLEX STEEL
• PRECIPITATION HARDENABLE STEEL
• SOFT STAINLESS STEEL
• APPLICATION OF SS IN ORTHODONTICS

4. ORTHODONTIC ARCHWIRES
• PROPERTIES
• PHASES OF ARCHWIRE DEVELOPMENT
• SS WIRE
• COBALT CHROMIUM
• AUSTRALIAN ARCHWIRE
• NICKEL TITANIUM ALLOYS
• ALPHA TITANIUM
• BETA TITANIUM
• ESTHETIC ARCHWIRE
• OPTIFLEX

5. 1937 ,SS CONFIRMED AS
ORTHODONTIC MATERIAL
SS,1919-KRUPPS DENTAL
POLYCLINIC BY
R.HAUPT MEYER
NOBLE METALS-
GOLD
ALLOY,Pt,Ir,Ag
GERMAN
SILVER,1887-
ANGLE
SS(LIGATURE
WIRES),1930-
ANGLE
SS,1912-
HARRY BREARLY of
SHEFFIELD

6. Internal force(per unit area)within a structure subjected to an external force
Relative change in the shape or size of an object due to
externally applied force

7. STRESS TYPES
COMPRESSIVE
STRESS-stress
that sqeezes
something
SHEAR
STRESS-stress
component
parallel to a
given surface
TENSIONAL
STRESS-stress
that pulls
something apart

8. ELASTIC LIMIT
It is a point at which any
permanent deformation
first observed

9. PROPORTONAL
LIMIT
GREATEST STRESS
PRODUCED IN A
MATERIAL SO THAT
Stress  Strain

10. YIELD
STRENGTH
PROPERTY THAT REPRESENTS THE
STRESS VALUE AT WHICH A
SMALL AMOUNT(0.1% OR
0.2%)OF PLASTIC
DEFORMATION OCCURED

11. Modulus of Elasticity
(Young’s modulus) (E)
RELATIVE STIFFNESS
OR RIGIDITY OF A
MATERIAL MEASURED
BY THE SLOPE OF THE
ELASTIC REGION OF
STRESS STRAIN
DIAGRAM

12. RANGE
• The distance that the wire
will bend elastically before
permanent deformation
occurs.

13. FORMABILITY
• amount of permanent deformation that a wire can
withstand before failing.
RESILIENCY
AREA UNDER THE STRESS STRAIN CURVE
UPTO PROPORTIONAL LIMIT.
13Strain
Stress
Resiliency Formability
Proportional limit
Yield strength

14. • When a loop is bent in a wire, it
is differentially stretched so
that the outer surface becomes
more workhardened and thus
has better spring properties
than the inner surface.
• If the spring is deflected in the
same direction as previous
bending , its elastic recovery is
better than if it is deflected in
opposite direction.
BAUSCHINGER EFFECT

15. • Iron based alloys Contain less than 1.2% carbon
• Stainless steel When chromium is added to steel(12% -
30%)
• Polymorphism-it crystallizes into more than one structure
(ferritic, martensitic & austenitic) property called ALLOTROPY.
• At room temp pure iron is BCC structure ferrite (alpha
form) stable till 912º C.
• At temp. between 912-1394ºC FCC Structure austenite
(gamma form)
STEEL

16. FUNCTION OF EACH CONSTITUENT:
1.Fe-Main constituent
2:Cr-Increases tarnish and corrosion resistance.
3. Ni -tarnish & corrosion resistance
4. C –hardness
5.Si - acts as deoxidizer & scavenger
6.Mn - acts as scavenger & increase hardness
7.Ti - inhibits precipitation of chromium carbide

17. CLASSIFICATION
TYPE AISI NO
FERRITIC 430
AUSTENITIC 302, 304, 316L
MARTENSITIC 400
ACCORDING TO AISI(AMERICAN IRON & STEEL INSTITUTE)

18. 18
BASED ON THE CROSS-
SECTION
SQUAREROUND RECTANGULAR
MULTISTRAND
ED
TWISTED

19. BASED ON
SIZE
19 GAUGE
20 GAUGE
21 GAUGE
SUPPLIED IN VARYING DIAMETERS RANGING
FROM 0.1 TO2.0MM FOR ROUND WIRES

20. ACCORDING TO CRYSTAL LATTICE STAINLESS
STEEL IS CLASSIFIED AS-
Cr Ni C
FERRITIC BCC 11.5 - 27% 0% 0.2%
AUSTENITIC FCC 16 - 26% 7 - 22% 0.25%
MARTENSITI
C
BCT 11.5 - 17% 0 - 2.5% 0.15 - 1.2%
SP LATTICE COMPOSITION

21. STEEL CRYSTAL STRUCTURE
FERRITE
MARTENSITE
AUSTENITE
• BCC
• Low solubility for C
• Stable at room
temp
• Distorted BCC – BCT
• Higher C solubility than Ferrite
• Metastable at room temp
• Results from quenching Austenite
• FCC
• Larger interstitial
sites, higher C
solubility
• Stable at high
temps
21

22. Austenite
• The austenite-martensite
phase transformation
occurs by non-diffusional,
distortion rearrangement
of atoms.
PHASE TRANSFORMATION IN
STEELS
22
• The austenite-ferrite
phase transformation
occurs by diffusional
rearrangement of
atoms.
Ferrite Martensite

23. 23
THE FERRITIC GROUP
Plain chromium stainless steels with varying chromium
content between 11% and 18%, but with low carbon content.
Moderate to good corrosion resistance
Not hardenable by heat treatment.
Magnetic
Formabilty is not as good as austenite
Little application in dentistry
TYPES

24. 24
Type 430
A 17% Chrome, low alloy Ferritic steel.
Good corrosion resistant properties up to about 800°C.

25. SUPERFERRITIC STEEL
• Belongs to the category having chromium as much as 19% to 30%
• Nickel free and highly corrosion resistant.
• Corrosion resistance is further achieved by containing small amount
of aluminium and molybdenum and very little carbon.

26. THE MARTENSITIC GROUP
• The first stainless steels commercially developed
• Relatively high carbon content (0.1 - 1.2).
• Contain 12 and 18% chromium.
26

27. 27
• Moderate corrosion resistance
• Hardened by heat treatment resulting in high strength and hardness.
• Poor weldability and is magnetic.
• Commonly used for knife blades, surgical instruments, shafts,
spindles and pins, pliers.
THE MARTENSITIC GROUP

28. 28
Type 410
A 13% Chrome, 0.15% Carbon alloy possessing good ductility and
corrosion resistance.
Can be easily forged and machined.
Exhibits good cold working properties.
THE MARTENSITIC GROUP

29. • Type 416
• Similar to Type 410 but has added Sulphur giving improved
machinability.
• Type 431
• A 17% Chrome, 2.5% Nickel, 0.15% max Carbon . Has superior
corrosion resistance to types 410 & 416 due to the Nickel.
29
THE MARTENSITIC GROUP

30. AUSTENITIC STAINLESS STEELS
 Most corrosion resistant of stainless steels.
 AISI 302 is the basic type containing 18% Cr, 8% Ni and 0.15%
carbon.
 Type 304 has similar composition, chief difference being that the
carbon content is limited to 0.08%.
 Both 302 and 304 may be designated as 18/8 stainless steel and
are most commonly used in orthodontics in form of bands and
wires.

31.  Type 316 L (0.03% max. carbon) -> employed for implants
 The 316 & 316 L types have been recently introduced and 316
differs in that it contains 2% more Nickel in addition to about
2% Molybdenum, thus improving its corrosion resistance
AUSTENITIC STAINLESS STEELS

32.  Austenitic FCC structure is unstable at lower temperature
where it tends to turn into BCC (ferrite).
 If austenizing elements (nickel, manganese and nitrogen) are
added highly corrosion resistant solid solution phase can be
preserved even at room temperature.
 If these elements are absent these steels even with high
chromium content are ferritic at room temperature.
AUSTENITIC STAINLESS STEELS

33. Generally, austenitic stainless steel is preferable to the ferritic
alloy because of :
• Greater ductility & ability to undergo more cold work
without breakage.
 Substantial strengthening during cold working.
 Greater ease of welding.
 Ability to overcome sensitization.
 Less critical grain growth.
 Comparative ease in formation.

34.  BANDS & TUBES
Bands- Also prepared from stainless steel. It is a stainless steel
strip that encircles the crown. Brackets are welded to bands.
 Tubes- allows the wire to slide through it .
 It may be rounded to square.
 It may be single or combination of several tubes-single,
double or triple.
USES OF SS IN ORTHODONTICS

35.  Steel remains the standard material for many years to be used for
brackets. But now recently titanium brackets have been introduced.
These are made by casting or metal strips stamped to shape. Casting
ones are more precise & accurate.
 There is mesh at the back of the bracket which is used for bonding.
However corrosion is a problem
BRACKETS

36. SUMMARY OF PROPERTIES
36

37.  PASSIVATION- Cr is added to steel as
passivating agent . It reacts to the
atmospheric oxygen to form its oxides
thus preventing corrosion.
• SENSITIZATION- Loss of corrosion
resistance of 18/8 stainless steel when
heated to high temperature due to
formation of Cr carbides. Hence its not
available to react with oxygen.
• Causes-high temp used in soldering &
welding
• Prevention-use low fusing flux & less
time

38. STABILIZATION
It is done to prevent sensitization. Here titanium is added to
6 times that of carbon in stainless steel. Ti has more affinity
to form carbides than Cr making Cr free to react with
oxygen. Such stainless steel are called stabilized stainless
steel

39. HEAT TREATMENT
• Use of heating or cooling normally to extreme
temperature to achieve a desired result.
• 2 types of heat treatment
• Softening heat treatment ANNEALING
• Hardening heat treatment TEMPERING

40. A) Annealing
Effects associated with cold working ( eg strain
hardening, lowered ductility and distorted grains ) can
be reversed by simple heating the metal. This process
is called annealing. The more severe the cold working,
more rapidly the effects can be reversed by annealing.
Annealing in general comprises of three stages :
1)Recovery
2) Recrystallization
3) Grain growth

41. RECOVERY
It is considered the stage at which the cold work
properties begin to disappear. There is slight decrease in
tensile strength and no change in ductility.
RECRYSTALLIZATION
• significant change in the microstructure
• Deformed grains replaced by new strain-free grains
• Original soft and ductile properties return
• Recrystallization occurs only if metal has been sufficiently cold
worked

42. GRAIN GROWTH
The recrystallized structure has a certain average grain size
depending on the number of nuclei. The more severe the cold working
the greater the number of such nuclei. Thus the grain size for the
completely recrystallized material can range from fine to fairly coarse. If
fine grain structure is further annealed,grain growth occurs to minimize
the grain boundary area,with large grains consuming the small grains.
The process continues till a course grain structure is produced.

43. CORROSION OF STAINLESS STEEL
 Defined as destruction or deterioration of material by a
chemical or electrochemical reaction.
 Causes-
 If surface in-homogenesity is present it allows corrosion
cells to form in presence of saliva.

44. Rust- It’s the formation of iron oxide when iron & steel alloy
corrodes. It may be brown, black or reddish in color. Can take
form of pits and blisters .
Catastrophic corrosion- When stainless steel is
sensitized as in brazing or welding & then exposed to
chemical agents then Cr depleted boundaries are readily
attacked by oxygen. This phenomenon is called as
catastrophic corrosion.

45. DUPLEX STEELS
 Consists of assembly of both austenite and ferrite grains
 28% Chromium, 6% Nickel, and equal amounts of Austenite
and Ferrite.
Along with Fe these steels have Mo and Cr and low amounts of
Ni.
As opposed to austenitic ones these steels are attracted to
magnets.
 When improperly heat treated there is a tendency to form a
brittle phase with very poor corrosion resistance (sigma
phase).
Used for manufacturing one piece brackets

46.  PRECIPITATION HARDENABLE STEELS (PH STEEL)- it
can be hardened by heat treatment. It has got high tensile
strength & thus widely used in mini brackets & edgelock
brackets.
 SOFT STAINLESS STEEL- it is the thoroughly annealed
steel to remove all the stresses incorporated during cold
working. These are commonly used as ligature wires

47. ARCH WIRES
 Stainless steel & Cobalt-Chromium has replaced precious metals
because of better properties like strength, springiness & equivalent
corrosion resistance. Can be softened by annealing and hardened by
cold working.
 Fully annealed wires are used ligature wires.
 Special type of stainless steel arch wire has been prepared by A J
Wilcock called Australian arch wire.

48. REQUIREMENTS OF AN IDEAL
ARCHWIRE (KUSY )
1. Esthetics
2. Stiffness
3. Strength
4. Range
5. Springback
6. Formability
7. Resiliency
8. Coefficient of
friction
9. Biohostability
10.Biocompatibility
11.Weldability
48

49. PROPERTIES

50. ---------PROPERTIES

51. STAINLESS STEEL WIRES
 Most important use of stainless steel in orthodontics is in the
form of wires.
 Used for making clasps, springs, bows, arch wires etc.
 It is dispensed in various thickness or gauges

52. PROPERTIES
 Low modulus of elasticity
 High flexibility
 High resiliency
 Easy to weld & solder
 Good corrosion resistance
 Easy to manipulate

53. ADA. SPECIFICATION NO.32
Alloy
Modulus Of
Elasticity
Yield Strength
(Mpa)
Utility Tensile
Strength
SS 179 GPA 1759 MPA 2117

54. APPLICATION OF SS IN CLINICAL
PRACTICE
• Types 302 and 304 of 18-8 stainless austenitic wires are used
in Orthodontics.
• For the tooth alignment and leveling phase even steel wires
with a smaller cross-section result in high loads, which are not
consistent with physiological forces.
• Used in making loops that increase the wire’s activation range
and disguise,as it were, the low resilience and high stiffness of
the wire.
Orthodontic wires: knowledge ensures clinical
Optimization - Dental Press J. Orthod 2009

55. • The disadvantage of using loops lies in the fact that as these
loops lose their original shape they change the direction of
force vectors. Loops can also hinder hygiene by entrapping
food particles. If not positioned properly, loops can damage
adjacent soft tissues.
• Stainless steel wires boast excellent resistance to corrosion
and exhibit higher elastic limits and modulus of elasticity,
Orthodontic wires: knowledge ensures clinical
Optimization - Dental Press J. Orthod 2009

56. AUSTRALIAN ARCH WIRE
 A J Wilcock of Australia came with a new wire called
Australian arch wire. It become famous because it
combines high resiliency with toughness.
 Wilcock’s archwire have been the mainstay of Begg’s
technique.
 Due to high resiliency its diameter is reduced to 0.018 -
0.014 inch
Application –it is highly useful in deep over bite correction as
it does not undergo permanent deformation

57.  Types :
a) Regular
b) Regular plus
c) Special
d) Special plus
e) Special plus pulse straightened
f) Premium
g) Premium plus
h) Premium plus pulse straightened
i) Supreme
j) Supreme pulse straightened

58. MULTI STRANDED OR BRAIDED WIRES-
 To increase the strength and to decrease the stiffness wire is
braided or twisted together by the manufacturer which
increases flexibility and can sustain large elastic deflection in
bending.
CO-AXIAL WIRE
• Has got a central core wire
with 5 outer wires wrapped
around .
• It increases resiliency &
flexibility
• It applies light continuous
force.
twist
coaxial
Straight
woven

59. WHEN TO USE MULTISTRANDED
STAINLESS STEEL ARCHWIRES
• By using multi-stranded stainless steel arch wires one can
employ stainless steel arch wires in the initial stage of tooth
alignment and leveling without the need for loops.
• The elastic recovery of multi-stranded wires is 25% higher
than that of a conventional stainless steel wire of identical
diameter.
Orthodontic wires: knowledge ensures clinical
Optimization - Dental Press J. Orthod 2009

60. • The rigidity of interbracket segments is much lower than that
of conventional stainless steel wires of identical diameter.
• Although less formable than conventional steel wires multi-
stranded wires are responsive to contours and bends, such as
omega loops for posterior tying, thus preventing tooth
projection.
Orthodontic wires: knowledge ensures clinical
Optimization, Dental Press J. Orthod 2009

61. • Following World War II, returning servicemen complained that
their Elgin watches couldn't take the punishment of corrosive
environmental situations in various theatres of the war.
• The Elgin Watch Company took those complaints to heart, and
after four years of research, "Elgiloy", a non-corroding watch
spring material with an infinite life span, was born.
• Introduced into orthodontics because their properties are
excellent for orthodontic purposes.
COBALT-CHROMIUM ALLOYS
History

62. • Available commercially as
• Elgiloy (Rocky Mountain Orthodontics),
• Azura (Ormco Corporation) and
• Multiphase (American Orthodontics).
• Elgiloy is manufactured in four tempers.
• Blue – soft.
• Yellow – ductile.
• Green –semi resilient
• Red-resilient
COBALT-CHROMIUM WIRES

63. Blue(soft)
• Softest –high formability. Recommended when considerable
bending soldering or welding is required. Heat treatment increases
its resistance to deformation.
Yellow (Ductile)
• More resilient than blue Elgiloy. Good formability. heat treatment
increases its strength and spring performance.
Green (Semi resilient)
• More resilient than yellow and can be shaped with pliers before
heat treatment.
Red (Resilient)
• Most resilient , high spring qualities. Withstands only minimal
working. Fractures easily after heat treatment, all adjustments
should be made before this precipitation hardening process.

64. NICKEL TITANIUM ALLOYS
• Nickel titanium alloys have certain characteristic properties associated with
them . These properties are primarily exhibited due to its crystal structure.
• At higher temperatures the crystal structure is that of a body centered
cubic(BCC) and is called AUSTENITE . At lower temperatures the crystal
structure is that of a hexagonal closed packed structure called MARTENSITE.
• The two most important properties of nickel titanium alloys are
1.Shape memory
2.Super elasticity

65. SUPERELASTICITY
• This is a mechanical equivalent of the change , which is
observed due to cooling of austenite.
• This is possible because the TTR for these alloys is very
close to room temperature.
• Kary has also called it PSEUDOELASTICITY.
• Whether,it is thermo or pseudo-elasticity, the transition
from martensite to austenite occurs with ease.

66. Stress strain curve

70. SHAPE MEMORY
• Shape memory refers to ability of a material to “remember”its
original shape after being plastically deformed while in the
martensitic form.
• Also called THERMELASTICITY.

71. HYSTERESIS
• When the austenitic nickel titanium wire is
stressed,it can be observed that the loading curve
differs from its unloading curve.
• The reversalibilty has an energy loss associated
with it,this is know as hysteresis.

72. CONVENTIONAL/STABILIZED
NICKEL-TITANIUM ALLOYS
• “Nitinol”was developed in the early 1960’s by William F.Buehler,a
research metallurgist at the Naval Ordinance Laboratory,Silver
springs,Maryland.
• Clinical use of nickel-titanium was started by Andreasen in
May,1972
• The shape memory effect(SME)had been suppressed by cold
working
• Proffit refers to these alloys as M-NiTi’s.

73. ADVANTAGES
• Low stiffness
• Outstanding range
• High sringback
• Disadvantages
• Lack of formability
• No shape memory,super elasticity and hysteresis

74. SUPERELASTIC NICKEL TITANIUM
ALLOYS(ACTIVE AUSTENITIC)
• Chinese NiTi developed by Dr.Tieun Hua Cheng
• Reported by BURSTONE(1985).
• Japanese NiTi produced by the Furukawa Electric Co.,which
was first reported by Miura(1986)
• These wires,in their”as received”condition were in the
austenitic phase,and they showed the property of
superelasticity.
• Superelasticity results from stress induction,as in archwire
ligation.

75. • “Hysteresis”is seen in these wires.
• Disadvanatges
• Wire bending is all bit impossible with these alloys.

76. NEW APPLICATION OF SUPERELASTIC
NITI RECTANGULAR WIRE
• (Miura 1990)in heat treatment,the superelastic NiTi alloy
not only changes its force level,but memorizes form.The
latter characteristic makes it possible to condition an
archwire so that it memorizes a particular
archform,including torque,angulation and buccolingual
movemens.The archwire can therefore be formed in the
laboratory ahead of time,rather than using precious
chairtime.The archform will also be more accurate than if it
were bent at chairside.

77. TYPES OF OF THERMODYNAMIC
NICKEL TITANIUM
• TYPE I:At temperature 10-15 C
• TYPE II:At temperature 27 C
• TYPE III: At temperature 35 C
• TYPE 1V:At temperature 40 C

78. COPPER NiTi
Rohit 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 wax to increase strength,decrese
hysteresis and to enhance the thermal reactive properties
of nickel titanium alloys.

79. • Due to decreased mechanical hysteresis in these wires it
makes it easier to insert larger rectangular wires without
patient discomfort.
• The addition of copper has enabled in the development of
new quarternary alloy with four constant transformation
temperatures for four distinct force levels,thus enabling
the clinician to select archwires on a case specific basis

80. • They are classified as
• Type I (at 15 degree Celsius)
Generate very high forces
Very few clinical indicatins
Type ii(at 27 degree Celsius)
Generates highest forces of the four types and is best used in
patients with healthy periodontium
When rapid tooth movement is required

81. Type iii(at 35 degree Celsius)
Generate tooth driving forces when the mouth temperature
exceeds 35 degree Celsius
These forces are intermittent in nature
Best used in patients who are sensitive to pain,compromised
periodontal condition
These variant would provide activation only after consuming
hot food and beverages

82.  Nickel is the most common metal to cause contact dermatitis in
orthodontics.
 Nickel-containing metal alloys, such as nickel-titanium and stainless
steel, are widely used in orthodontic appliances.
 Nickel-titanium alloys may have nickel content in excess of 50 per
cent and can thus potentially release enough nickel in the oral
environment to elicit manifestations of an allergic reaction.
BIOCOMPATIBILITY
NICKEL SENSITIVITY

83. NICKEL FREE STAINLESS STEEL
 Recently new kind of nearly nickel free austenitic stainless steel
was developed and introduced to the market.
 Alloyed with 15-18% chromium, 3-4% molybdenum, 10-14%
manganese, and about 0.9%nitrogen to compensate for nickel.
 High corrosion resistance.
 The low nickel concentration results in the reduction of nickel
allergy potential.
 Orthodontic wires under the name Manzanium (Scheu), or
Noninium (Dentaurum) are already in the market. Unfortunately
the melting and forming of this steel is very costly.

84. ALPHA TITANIUM
PURE TITANIUM:
• Below 885 C- Hexagonal closed packed or alpha lattice is
available.
• At higher temperature-body centered cubic or beta crystal
• HCP-Possess few slip planes
• Gets hardened by absorbing intraoral free hydrogen ions ,
which turn it into titanium hydride, at the oral temperature
of 37 C and 100% humidity.
• Any modification should be done within 6 weeks-
Mollenhauer

85. BETA TITANIUM
(TITANIUM MOLYBDENUM ALLOY OR
T.M.A.)
• Introduced by Dr. Burstone(1980)
• COMPOSITION
• 80% TITANIUM
• 11.5% MOLYBDENUM
• 6% ZIRCONIUM
• 4.5% TIN

86. ADVANTAGES OF T.M.A. V/S NITINOL
• SMOOTHER
• WELDABLE
• GOOD FORMABILITY
ADVANTAGES OF T.M.A V/S S.S.
• GENTLER FORCES
• MORE RANGE
• HIGHER SPRINGBACK
DRAWBACK: HIGH COEFFICIENT OF FRICTION

87. LOW FRICTION T.M.A.
• Introduced by Ormco
• Done by ion implementation bean mechanism
T.M.A COLOURS
• Also developed by Ormco
• Implantation of oxygen and nitrogen ions
• Ensures colour fastness

88. property SS CO-Cr-Ni TMA Ni-ti
COST LOW LOW HIGH HIGH
FORCE
DELIVERY
HIGH HIGH INTERMEDIAT
E
HIGH
ELASTIC
RANGE
(SPRINGBACK)
LOW LOW INTERMEDIAT
E
HIGH
FORMABILITY EXCELLEN
T
EXCELLENT EXCELLENT POOR
EASE OF
JOINING
CAN BE
SOLDERED
& WELDED
CAN BE
SOLDERED
&WELDED
TRIED
WELDABILITY
CANNOT BE
SOLDERED
OR WELDED
ARCHWIRE
BRACKET
FRICTION
LOWER LOWER HIGHER HIGHER
BIOCOMPATABI
LTY
SOME SOME SOME

89. NOMOGRAMS
89

90. NOMOGRAMS
• With the nomograms shown it is clear that the Stainless steel
wire is the stiffer wire with low range of action and more
strength.
• Ni-Ti wires has good range of action but with decreased
stiffness and strength
• Beta titanium has good amount of range of action but less
stiffer than that of the s.s

91. ESTHETIC ARCHWIRE
• Composites: can be composed of ceramic fibers that are embedded
in a linear or cross-linked polymeric matrix.
• Developed by a process known pultrusion.

92. OPTIFLEX
• Made of clear optical fibre ;comprises of three layers:
1. A silicon dioxide core
2. A silicon resin middle layer
3. A stain resisted nylon outer layer.

93. PROPERTIES
• The most esthetic orthodontic arch wire to date.
• completely stain resistant
• Exerts light continuos force
• Very flexible

94. OTHER ESTHETIC ARCHWIRES
• E.T.E coated Nickel titanium(E.T.E-ELLASTOMERIC POLY
TETRA FLORETHYLENE EMULSION).
• Stainless steel or nickel titanium archwire bonded to a
tooth coloured EPOXY coating

95. CONCLUSION
• It can be seen that not archwire meets all the requirements of
orthodontists.We still have long way to go,in terms of finding the
“ideal” archwire.But with such progress in science and technology,I
am sure that we will see significant improvements in archwires in
the near future.
• Also, we must consider ourselves fortunate to have wide array of
materials to choose from.Just imagine working with just a single
type of gold alloy wire,like they used to not so long ago.So we
should appreciate this fact and try to make the most of what we
have.

96. • Dr.Rajkumar.Alle.
• Dr. Shwetha.
• Dr.Shashikumar.
• Dr.Suma.
• Dr.Kiran.
• Dr.Lokesh.
• Dr.Dharmesh.
• Dr.Prabhavati
• Dr.Siddharth

97. REFERENCES
1.Science of Dental materials , Anusavice
2.Dental Materials – Craig.
3.Contemporary orthodontics-William.R.Proffit,Henry.W.Fields,David M.
Sarver
4.Mechanical principles and clinical applications of orthodontic wires –
Sunil Kapila and Rohit Sachdeva – AJO August 1989.
5.Mechanical properties of Orthodontic wires in tension bending and
torsion. AJO 1982 September – Scot R. Drake, Kamal Asgar, John M.
Powers.
6.Orthodontics Current Principles and Techniques – Thomas M. Graber
and Robert L. Vanarsdall. Comparison of nickel-titanium and beta
titanium wire sizes to conventional orthodontic arch wire materials AJO-
1981 Jun- Kusy
7.Effect of composition and cross section on elastic properties of
orthodontic wires-AO-kusy and greenburg volume 51 no 4 october 1981.
REFERENCES

98. 8.Cátia Cardoso Abdo Quintão et al, Orthodontic wires:
knowledge ensures clinical optimization, Dental Press J.
Orthod., nov./dec. 2009
REFERENCES