Aesthetic Wires

 

Jannathulferidoz

Department of Dental Materials, Saveetha Dental College, Chennai, India.

 

ABSTRACT:

Aim:To review about the  aesthetic wires. Objectives::To know more about, mechanical, colour, and roughness properties of  the aesthetic orthodontic wires by understanding the research studies and collecting review articles.

Background: Aesthetic wires can be separated into two: coated metal and transparent nonmetallic. Each undergoes a distinct manufacturing process, resulting in unique challenges when used in treatment. Orthodontic appliances are metallic and silver in color and at the beginning esthetic production, there were transparent brackets made of ceramic or composite. Due its colour and aesthetic properties it is preferred by patients.

 

 

INTRODUCTION:

Orthodontic mechanics is based on the principle of elastic energy storage and its conversion into mechanical work through tooth movement. Since orthodontic treatments extend over a number of months and more and more adult patients were undergoing orthodontic treatment, the aesthetic aspect of the appliance could not be ignored any more¹.The demand for aesthetic orthodontic appliances is increasing, and the development of materials that present acceptable aesthetics for the patients and an adequate clinical performance for clinicians is needed. Most of the orthodontic appliances are metallic and silver in colour and at the beginning aesthetic production, there were transparent brackets made of ceramic or composite. But the arch-wires are still made of metals such as titanium molybdenum alloy, nickel titanium, or stainless steel². Recently, coated metallic and Fiber-reinforced wires have been introduced to solve aesthetic appearance problem. Ideal features of aesthetic are mechanical  properties, Correct dimensions, Biocompatible, Pleasantly aesthetic ,Consistent with the translucency of aesthetic brackets and different hues of the teeth.³

 

Methods and Materials :

Aesthetic arch-wires can be separated into two categories:

(1) Coated Metal and (2) Transparent Nonmetallic^4.

 

Different of Types of Aesthetic Wires

Coated Metal Arch-Wires

Coated metal arch-wires are nickel-titanium or stainless steel wires treated with a polytetra- fluoroethylene (PTFE), epoxy- resin, parylene-polymer, or less commonly palladium covering to impart an enamel hue⁵. Manufactures vary with regard to the coating material, thickness of the coating, and steps within the application process to maximize aesthetics, flake- resistance, and mechanical efficiency ^6.

 

Teflon Coated Stainless Steel :

Coating on arch-wire material has been introduced to enhance aesthetics and decrease friction. These wires are designed to be aesthetically more acceptable by the patient. They are given a plastic tooth coloured coating so that it can blend with the tooth colour and also of ceramic brackets. Normally the coating is 0.002” thick^7. The coating frequently used is TEFLON .PTFE coating is applied to an orthodontic wire by thermal spraying, a process in which finely heated materials are sprayed in a molten condition onto a surface to form a coating⁸.Thermal spraying of PTFE onto an orthodontic arch-wire entails: (1) surface treatment of the wire by sandblasting (50-micron alumina) to support coating adhesion, (2) “masking” or covering with tape areas that are not be treated, (3) air-spraying atomized PTFE particles with clean compressed air to coat the wire, (4) baking in a chamber furnace to cure the coating onto the wire, and (5) removal of the masking tape.⁹The coating is applied by an atomic process that forms a layer of about 20-25μm thickness on the wire. This layer then undergoes a heating process and acquires a surface with excellent sliding properties and substrated adhesion. It should also be noted that Teflon coating protects the underlying wire from the corrosion process. However, since this coating is subject to flaws that may occur during clinical use, corrosion of the underlying wire is likely to take place after its prolonged use in the oral cavity ^10-12

 

Available in Natural tooth  shades

Coloured-Blue, Green, and purple as Lee White wires

 

Epoxy resin coated :Epoxy is a synthetic resin made by combining epoxide with another com pound. Primarily recognised for its excellent adhesion, epoxies display a broad range of physical properties, such as chemical resistance, electrical insulation, and dimensional stability^12..Epoxy-resin coating is applied to an orthodontic arch wire by electrostatic coating, or E-coating. Electrostatic coating is a process that uses electrostaticallycharged particles to more efficiently coat a workpiece. Electrostatic coating of epoxy resin onto an arch-wire entails: (1) applying a high-voltage electrostatic charge to the arch- wire, (2) applying an opposing electrostatic charge to the epoxy, (3) air-spraying atomised liquid epoxy particles to the wire, and (3) baking in a chamber furnace to cure the coating onto the wire.¹³

 

Availability :

Epoxy coated arch-wires are available under the trade name of Filaflex (American Orthodontics), have high tensile stainless steel core and durable tooth coloured plastic coating.This is available in preformed round 0.018” arches. They are available under another brand name of Orthocosmetic Elastinol^13-14.

 

Nickel Titanium Aesthetic Arch-Wires :

• Structure: It is a super-elastic Ni-Ti wire with special plastic and friction reducing tooth coloured coatings which blends with natural dentition, ceramic, plastic and composite brackets and maintains its original Colour.The coated white coloured wires have routinely succumbed to forces of mastication and enzyme activity of oral cavity¹³

 

Availability :

It is marketed by Ortho Organizers and is available in round 0.014”, 0.016”, 0.018” and rectangular 0.016” x 0.022” sizes. These wires deliver gentle force.^10-13

 

Transparent Nonmetallic Arches :

The significant advancements have been made to create nonmetallic arches whose properties resemble metal alloys. Flexible nonmetallic arches are typically made from glass spindles embedded in a polymeric matrix. Some examples of nonmetallic arches include fiber-reinforced polymer (FRP) or newer self-reinforced polymer^14.

 

Composite Wires :

The use of composites which can be a mixture of ceramic fibers that are embedded in a linear or cross linked polymeric matrix .Such an arch-wire could be made with a tooth-coloured appearance and with stiffness properties similar to metallic arch-wires.

An aesthetic arch-wire with excellent overall properties involves use of COMPOSITES^15.

 

Colour Stability of Esthetic Arch Wires:

The colour stability of esthetic arch-wires during orthodontic treatment is clinically important Ideally, the colour of esthetic wires should match that of teeth and esthetic brackets. But the colours of natural teeth differs according to colour measurement protocols used and by race, age, and gender.¹⁵Elayyan et al stated that coated arch-wires had low esthetic value because 25% of coating was lost within 33 days in vivo and surface quality revealed severe deterioration¹⁶

 

Mechanical Properties of Esthetic Arch Wires:

 Mechanical properties of orthodontic arch-wires can be determined by 3-point bending test. Elayyan et al stated that"retrieved coated arch-wires produce lower unloading force values than as received coated arch-wires with conventional ligation¹⁵Further research are needed to develop the mechanical properties of Esthetic  wires

 

Surface Roughness of Esthetic Wires :

Another important topic for the esthetic wire is surface roughness. The surface quality of wires affects the area of surface contact and influences its corrosion behavior and biocompability¹⁵.The surface topography of an orthodontic wire is an essential property known to influence its mechanical characteristics, esthetic appearance, corrosion behaviour, and/or its biocompatibility. Clinically, a rough surface encourages greater plaque accumulation, influences its friction properties, and increases corrosion and color instability.There are lots of methods to determine surface roughness such as atomic force microscopy, spectroscopy, and contact surface profilometry.Elayyan et al stated that surface roughness of esthetic arch-wires increases after usage in vivo^17.

 

CONCLUSION :

Appearance is one of the patients' main concerns during orthodontic treatment. There is a growing demand for esthetic orthodontic appliances and by the effect of this demand, different types of wires are introduced. Appropriate use of all the available wire types may enhance patient comfort and reduce chair-side time as well as the duration of treatment. The new esthetic appliances provided better Colour stability, mechanical strength  for the patients and acceptable results for clinicians but these appliances must be studied by the researchers more and also must be developed^18-20.

 

REFERENCE :

1.     Singh DP (2016) Esthetic Archwires in Orthodontics- A Review. J Oral Hyg Health 4:194. doi: 10.4172/2332-0702.1000194.

2.     Aksakalli S, Malkoc S. Esthetic orthodontic archwires: Literature review. J Orthod Res [serial online] 2013 [cited 2016 Jun 9];1:2-4.

3.     NEAL D. KRAVITZ, DMD.ESTHETIC arch wires-A review

4.     Dr. Rakesh Nathani, Dr. Pallavi Daigavane, Dr. Sunita Shrivastav, Dr. Ranjit Kamble, Dr. Deoashish Gupta. Esthetic archwires. International Journal of Advanced Research (2015), Volume 3, Issue 12, 743 – 751.

5.     Aesthetic Archwires By Neal D. Kravitz, DMD, MS.

6.     Cross-section dimensions and mechanical properties of esthetic orthodontic coated archwire American Association of Orthodontists. Published by Elsevier Inc.

7.     Orthodontic Materials ,scientific and clinical aspect,William A Brantly.

8.     Vogels DS (1991) Orthodontic archwires. J Clin Orthod 25: 83-98.

9.     9.)Kaphoor AA, Sundareswaran S. Aesthetic nickel titanium wires--how much do they deliver? Eur J Orthod 2012;34:6039.

10.  Kusy RP. Orthodontic biomaterials:from the past to the present. Angle Orthod 2002;72:501-12.

11.  Stegner  D, Ibe D. Properties of superelastic wires and their relevance to orthodontic treatment. Eur J Orthod 1995;17:395-402.  

12.  Burstone et al.Fiber Reinforced Composite Arch-Wires in Orthodontics JCO2000:37

13.  Washington B, Evans CA, Viana G, Bedran-Russo A, Megremis S. Contemporary esthetic nickel-titanium wires: do they deliver the same forces? Angle Orthod. 2015;85:95–101.

14.  Bourauel C, Fries T, Drescher D, Plietsch R. Surface roughness of orthodontic wires via atomic force microscopy, laser specular reflectance, and profilometry. Eur J Orthod. 1998;20:79–92.

15.  Doshi UH, Bhad-Patil WA. Static frictional force and surface roughness of various bracket and wire combinations. Am J Orthod Dentofacial Orthop. 2011;139:74–79.

16.  16.)Elayyan F, Silikas N, Bearn D. Mechanical properties of coated superelastic archwires in conventional and self-ligating orthodontic brackets. Am J Orthod Dentofacial Orthop 2010; 137: 213-7.  

17.  Elayyan F, Silikas N, Bearn D. Ex vivo surface and mechanical properties of coated orthodontic archwires. Eur J Orthod 2008; 30: 661-13.)

18.  Stober T, Gilde H, Lenz P. Color stability of highly filled composite resin materials for facings. Dent Mater 2001;17:87-94.

19.  Eliades T, Gioka C, Heim M, Eliades G, Makou M. Color stability of orthodontic adhesive resins. Angle Orthod 2004;74:391-3.

20.  Krishnan V, Kumar KJ. Mechanical properties and surface characteristics of three archwire alloys. Angle Orthod 2004; 74: 825-31.

 

 

Accepted on 20.07.2016           © RJPT All right reserved

Research J. Pharm. and Tech 2016; 9(11):2053-2055.