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

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Page 1: Newer Wires / orthodontic courses by Indian dental academy

NEWER ORTHODONTIC WIRES INDIAN DENTAL ACADEMY

Leader in continuing dental education www.indiandentalacademy.com

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Page 2: Newer Wires / orthodontic courses by Indian dental academy

INTRODUCTIONOrthodontic 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

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Page 3: Newer Wires / orthodontic courses by Indian dental academy

High stored energy Good formability Bio compatibility & environmental stability

Low surface friction Capability to be welded or soldered to auxiliaries

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Page 4: Newer Wires / orthodontic courses by Indian dental academy

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:

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Page 5: Newer Wires / orthodontic courses by Indian dental academy

PROPERTY

STAINLESS STEEL

Co – Cr - Ni

TMA Ni - Ti

Cost Low Low high high Force delivery

High High intermediate

light

Spring back

Low Low Intermediate

High

Formability

Excellent Excellent Excellent Poor

Ease of joining

Soldered, welded joints - reinforced

Soldered, welded joints - reinforced

True weldability

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”

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Page 6: Newer Wires / orthodontic courses by Indian dental academy

COPPER NiTi

• 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.

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

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Page 7: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 8: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 9: Newer Wires / orthodontic courses by Indian dental academy

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

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Page 10: Newer Wires / orthodontic courses by Indian dental academy

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

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Page 11: Newer Wires / orthodontic courses by Indian dental academy

BETA TITANIUM ( TMA)

The beta titanium wire has a unique balance of

low stiffness

high spring back

Formability

Weldability

Source: Burstone, AJO-DO:1980 feb

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COMPOSITION

•Molybdenum - 11.3%

•Tin - 4.3%

•Zirconium - 6.6%

•Titanium - 77.8%

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Page 13: Newer Wires / orthodontic courses by Indian dental academy

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..

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Page 14: Newer Wires / orthodontic courses by Indian dental academy

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

3. It can be perfectly shaped to patients arch form

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Page 15: Newer Wires / orthodontic courses by Indian dental academy

DISADVANTAGE

•High coefficient of friction:

Therefore it is disadvantageous in sliding mechanics.

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Page 16: Newer Wires / orthodontic courses by Indian dental academy

COLOURED TMA

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.

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

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Page 17: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 18: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 19: Newer Wires / orthodontic courses by Indian dental academy

ADVANTAGESCompressive 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.

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Page 20: Newer Wires / orthodontic courses by Indian dental academy

Through an exclusive spi- spectrum ion beam implantation process ORMCO has introduced TMA colours.

Colored wires produced by varying ion type and thickness.

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Page 21: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 22: Newer Wires / orthodontic courses by Indian dental academy

Alpha titanium

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.

Introduced by Mollenhauer in 1988

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Page 23: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 24: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 25: Newer Wires / orthodontic courses by Indian dental academy

TIMOLIUM

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.

Source: European Journal of Orthodontics; Vol 26: 2004

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Page 26: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 27: Newer Wires / orthodontic courses by Indian dental academy

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

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Page 28: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 29: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 30: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 31: Newer Wires / orthodontic courses by Indian dental academy

Clinical use:

-used in phase 1 of treatment.

-any application including combination anchorage.

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

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Page 32: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 33: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 34: Newer Wires / orthodontic courses by Indian dental academy

COMPOSITE WIRE

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.

Source: Eur Jou of Ortho;22:2000

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Page 35: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 36: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 37: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 38: Newer Wires / orthodontic courses by Indian dental academy

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

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Page 39: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 40: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 41: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 42: Newer Wires / orthodontic courses by Indian dental academy

FRP ESTHETIC ORTHODONTIC WIRE

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.

Source: Journal of Biomaterials;Aug:1997

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Page 43: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 44: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 45: Newer Wires / orthodontic courses by Indian dental academy

Coated composite wires

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.

Source: Angle Orthodontist;Vol 70:2000

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Page 46: Newer Wires / orthodontic courses by Indian dental academy

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).

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Page 47: Newer Wires / orthodontic courses by Indian dental academy

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

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Page 48: Newer Wires / orthodontic courses by Indian dental academy

Esthetic wires

MARSENOLSource: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.

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Page 49: Newer Wires / orthodontic courses by Indian dental academy

The coating adheres to the wire and remains flexible.

The wire delivers constant force over long periods of activation and is fracture resistant.

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Page 50: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 51: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 52: Newer Wires / orthodontic courses by Indian dental academy

Super cable

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.

Source: JCO,Apr 1998

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Page 53: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 54: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 55: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 56: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 57: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 58: Newer Wires / orthodontic courses by Indian dental academy

Teflon coated ligatures

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.

Source: Angle Orthodontist; No 1:1995

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Page 59: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 60: Newer Wires / orthodontic courses by Indian dental academy

Stress relaxing composite ligature wires.

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.

Source: Angle Orthodontist, Vol 69;1999

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Page 61: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 62: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 63: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 64: Newer Wires / orthodontic courses by Indian dental academy

Organic polymer wire for esthetic maxillary retainers

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.

Source: JCO;Vol 30:May 1996

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Page 65: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 66: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 67: Newer Wires / orthodontic courses by Indian dental academy

Maxillary retainer with QCM organic polymer wire.

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

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Page 68: Newer Wires / orthodontic courses by Indian dental academy

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 theflat bow retainer wire. After heat treatment it displayed littlede formation.

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Page 69: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 70: Newer Wires / orthodontic courses by Indian dental academy

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.

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Page 71: Newer Wires / orthodontic courses by Indian dental academy

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