EP1573083A2 - Orthodontischer bogendraht aus metall und herstellungsverfahren dafür - Google Patents
Orthodontischer bogendraht aus metall und herstellungsverfahren dafürInfo
- Publication number
- EP1573083A2 EP1573083A2 EP03809995A EP03809995A EP1573083A2 EP 1573083 A2 EP1573083 A2 EP 1573083A2 EP 03809995 A EP03809995 A EP 03809995A EP 03809995 A EP03809995 A EP 03809995A EP 1573083 A2 EP1573083 A2 EP 1573083A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- titanium
- molybdenum alloy
- phase
- nitrogen
- inert gas
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 238000000034 method Methods 0.000 title claims description 18
- ZPZCREMGFMRIRR-UHFFFAOYSA-N molybdenum titanium Chemical compound [Ti].[Mo] ZPZCREMGFMRIRR-UHFFFAOYSA-N 0.000 claims abstract description 29
- 229910001182 Mo alloy Inorganic materials 0.000 claims abstract description 21
- 239000010936 titanium Substances 0.000 claims abstract description 18
- 239000000463 material Substances 0.000 claims abstract description 14
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 13
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 claims abstract description 9
- 239000002344 surface layer Substances 0.000 claims abstract description 7
- -1 titanium nitrides Chemical class 0.000 claims abstract description 7
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 claims abstract description 6
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims abstract description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 16
- 238000011282 treatment Methods 0.000 claims description 13
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 12
- 229910052757 nitrogen Inorganic materials 0.000 claims description 8
- 229910052786 argon Inorganic materials 0.000 claims description 6
- 229910052751 metal Inorganic materials 0.000 claims description 6
- 239000002184 metal Substances 0.000 claims description 6
- 238000005121 nitriding Methods 0.000 claims description 6
- 239000011261 inert gas Substances 0.000 claims description 5
- 239000000203 mixture Substances 0.000 claims description 5
- 238000005468 ion implantation Methods 0.000 claims description 4
- 230000005495 cold plasma Effects 0.000 claims description 3
- 150000002500 ions Chemical class 0.000 claims description 3
- 238000010583 slow cooling Methods 0.000 claims description 2
- 238000002513 implantation Methods 0.000 claims 3
- 229910001220 stainless steel Inorganic materials 0.000 description 8
- 239000010935 stainless steel Substances 0.000 description 7
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 6
- 229910045601 alloy Inorganic materials 0.000 description 6
- 239000000956 alloy Substances 0.000 description 6
- 238000005452 bending Methods 0.000 description 5
- 229910001040 Beta-titanium Inorganic materials 0.000 description 4
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 230000007797 corrosion Effects 0.000 description 3
- 238000005260 corrosion Methods 0.000 description 3
- 238000006073 displacement reaction Methods 0.000 description 3
- 230000003068 static effect Effects 0.000 description 3
- 238000003466 welding Methods 0.000 description 3
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 230000005489 elastic deformation Effects 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 229910052750 molybdenum Inorganic materials 0.000 description 2
- 239000011733 molybdenum Substances 0.000 description 2
- 229910052759 nickel Inorganic materials 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 238000004381 surface treatment Methods 0.000 description 2
- 239000000120 Artificial Saliva Substances 0.000 description 1
- 241000282465 Canis Species 0.000 description 1
- 208000002064 Dental Plaque Diseases 0.000 description 1
- 229910001069 Ti alloy Inorganic materials 0.000 description 1
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 229910000963 austenitic stainless steel Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229910000734 martensite Inorganic materials 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 229910001000 nickel titanium Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- SOQBVABWOPYFQZ-UHFFFAOYSA-N oxygen(2-);titanium(4+) Chemical class [O-2].[O-2].[Ti+4] SOQBVABWOPYFQZ-UHFFFAOYSA-N 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 210000003296 saliva Anatomy 0.000 description 1
- 238000005482 strain hardening Methods 0.000 description 1
- 230000035882 stress Effects 0.000 description 1
- 230000008646 thermal stress Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
- A61C7/00—Orthodontics, i.e. obtaining or maintaining the desired position of teeth, e.g. by straightening, evening, regulating, separating, or by correcting malocclusions
- A61C7/12—Brackets; Arch wires; Combinations thereof; Accessories therefor
- A61C7/20—Arch wires
Definitions
- the present invention relates to a metal wire usable in particular in the medical sector and in particular in orthodontics, for correcting anomalies in the position of the teeth.
- the correction of anomalies in the position of the teeth is most often carried out by subjecting the tooth or teeth concerned to a force varying in intensity and in direction for a determined duration. These forces are transmitted to the teeth by means of an orthodontic wire, connected, by means of ligatures, to fasteners glued to the teeth concerned.
- the orthodontic wire must have high mechanical characteristics, and must in particular have:
- tooth movement is carried out by sliding the attachments on the orthodontic wire which serves as a guide. Friction forces play a role in all forms of sliding.
- the dental displacement along an orthodontic wire due to a sliding mechanism, consists of a succession of inclinations, then of rectifications by small increments.
- the movement therefore depends more on static friction than on kinetic friction.
- One of these categories relates to austenitic stainless steel wires, which have varying shades and heat treatments but which are all characterized by high tensile strength and yield stress, a high modulus of elasticity, a low coefficient of friction on the fasteners.
- Another category of wires is based on a nickel-titanium alloy, in which nickel stabilizes the phase ce of the titanium which can transform into martensite under the effect of mechanical or thermal stresses.
- this alloy With a composition of 52% nickel, 45% titanium and 3% cobalt, this alloy exhibits, after work hardening, rubbery properties. Its modulus of elasticity is very low, its tensile curve is very different from that of a conventional alloy, and the wire deforms elastically or breaks; therefore the possible types of curvature are limited and this alloy is only sold in the form of preformed orthodontic wires.
- a third category of wires concerns those made of a titanium-molybdenum alloy.
- Titanium-molybdenum was introduced into the orthodontic world by Burstone for the company Ormco, after being developed by the metallurgist Goldberg of the Institute of Materials Science in Connecticut in 1979. Its composition is as follows:
- Titanium has been used in metallurgy since 1952 and it was in 1960 that a particular form of high temperature titanium alloy was developed. In fact, titanium can crystallize according to two systems:
- the Young's modulus measured for titanium-molybdenum wires corresponds to half of that measured for stainless steel wires, however the elastic limit is approximately identical.
- the use of the titanium-molybdenum alloy to produce orthodontic wires has a certain number of advantages compared to the use of stainless steel.
- the intensities of the forces developed are lower than those developed by stainless steel, and titanium-molybdenum allows elastic deformation of greater amplitude. As a result, the force restored by the wire remains weaker, more constant and works longer.
- titanium-molybdenum wires can be bent over a distance twice as long, without permanent deformation. This allows a greater field of action, either in the initial alignment of the teeth, or for the wires used in the finishes. This results in a large amplitude elastic deformation, while developing moderate and more durable forces. Due to its low rigidity (stiffness coefficient of 0.42 compared to stainless steel), the titanium-molybdenum alloy can be used to make wires with large sections, at a much earlier stage of orthodontic treatment ; this allows a greater filling of the grooves of the fasteners, and therefore better three-dimensional control of the teeth carrying the fasteners.
- titanium-molybdenum can be welded to itself, by electrical welding, without adding metal. It has good resistance to corrosion and is bio-compatible.
- the wires made of titanium-molybdenum (beta-titanium) have a unique balance of low rigidity, high maximum flexion, certain malleability, making them particularly reliable in a large number of orthodontic treatment methods.
- titanium-molybdenum alloy gives rise to a certain number of drawbacks, the most important of which lies in the fact that it generates higher friction forces than stainless steel, which is a brake on dental displacement. in sliding mechanics, for example during canine retractions or space closings.
- the object of the present invention is therefore to fill this gap, by proposing a metal wire suitable for use in orthodontics, in association with fasteners glued to the teeth, to correct position anomalies of the latter, made of a material having high mechanical performance and a very low coefficient of friction on said fasteners.
- such a wire is characterized in that the material of which it is made is defined by a basic structure made of a titanium-molybdenum alloy which comprises, in its outer surface layer, titanium nitrides of TiN type, TiN, free of titanium oxide.
- Another object of the invention is also to propose a process for obtaining the material defined by a basic structure made of a titanium-molybdenum alloy comprising, in its outer surface layer, titanium nitrides of TiN, Ti 2 N type , free of titanium oxide.
- Such a method mainly consists in carrying out a treatment for implanting the surface of N + and N ++ ions in the outer surface layer of the titanium-molybdenum alloy, by operating in a vacuum enclosure, at a temperature below 450 ° C.
- This treatment makes it possible to preserve the mechanical properties of the conventional titanium-molybdenum alloy while considerably improving its coefficient of friction.
- titanium nitrides TiN and Ti 2 N. Because ion implantation is carried out in the absence of oxygen, the creation of titanium oxides is avoided which would degrade the coefficient of friction and limit nitriding.
- the treatment is carried out during two consecutive phases, first of all carrying out a depassivation and a rise in temperature by non-reactive cold plasma (introduction of a gas inert (such as for example argon) this for approximately 45 minutes, then by carrying out a nitriding obtained always by cold plasma with the introduction of a mixture of inert gas, for example argon, and nitrogen, for approximately 200 minutes .
- a gas inert such as for example argon
- the entire treatment is carried out at a temperature below 450 ° C.
- the proportions of argon and nitrogen used during the nitriding phase must be adapted to the volume of the enclosure but must be such that there is enough nitrogen for it is implanted and enough argon to dissociate the nitrogen.
- the present method provides, according to another characteristic, to complete the surface treatment as previously described by a slow cooling phase.
- such a treatment advantageously provides a wire in which, so to speak, all the mechanical characteristics inherent in the classic titanium-molybdenum alloy and which are considered to be the best in the current state of the art in orthodontics. , are kept.
- the material according to the present invention also makes it possible to appreciably improve the friction of the orthodontic wire on the fasteners to be equivalent to, or even greater than, that of stainless steel, considered by all users as the reference. in this area.
- the connections between the orthodontic wires and the fasteners are tested by a process with reciprocating movement, in which a fastener is glued to a metal pivot.
- the wire applied to this fastener is held in place by an elastomeric tie; the whole is lubricated by artificial saliva.
- the test machine alternately pulls the wire with a fixed stroke of 5 mm. This reciprocating movement is repeated more than 100 times per test.
- the average amplitude of the forces measured by the test machine, with each movement, characterizes, in a comparative way, the importance of the static friction between the wire and the fastener.
Landscapes
- Health & Medical Sciences (AREA)
- Oral & Maxillofacial Surgery (AREA)
- Dentistry (AREA)
- Epidemiology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Dental Tools And Instruments Or Auxiliary Dental Instruments (AREA)
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR0216265A FR2848810B1 (fr) | 2002-12-19 | 2002-12-19 | Fil orthodontique a caracteristiques mecaniques elevees et a faible frottement dans les attaches |
| FR0216265 | 2002-12-19 | ||
| PCT/FR2003/050183 WO2004056283A2 (fr) | 2002-12-19 | 2003-12-17 | Fil metallique du type utilise en orthodontie et son procede d'obtention |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| EP1573083A2 true EP1573083A2 (de) | 2005-09-14 |
Family
ID=32406239
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP03809995A Withdrawn EP1573083A2 (de) | 2002-12-19 | 2003-12-17 | Orthodontischer bogendraht aus metall und herstellungsverfahren dafür |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US20060204919A1 (de) |
| EP (1) | EP1573083A2 (de) |
| JP (1) | JP2006510426A (de) |
| AU (1) | AU2003302185A1 (de) |
| FR (1) | FR2848810B1 (de) |
| WO (1) | WO2004056283A2 (de) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101808595B (zh) * | 2007-06-11 | 2017-05-10 | 史密夫和内修有限公司 | 层状陶瓷医疗植入物 |
| US8569625B2 (en) | 2009-12-22 | 2013-10-29 | W. C. Heraeus Gmbh | Joined dissimilar materials |
| US8487210B2 (en) | 2010-06-11 | 2013-07-16 | W. C. Hereaus GmbH | Joined dissimilar materials and method |
| FR2982618B1 (fr) | 2011-11-10 | 2014-08-01 | Institut Nat Des Sciences Appliquees De Rennes Insa De Rennes | Procede de fabrication d'un alliage a base de titane pour dispositifs biomedicaux |
| RU2536843C1 (ru) * | 2013-09-05 | 2014-12-27 | Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Московский государственный индустриальный университет" | Способ ионной имплантации поверхностей деталей из титанового сплава |
| CN106796381A (zh) | 2014-10-03 | 2017-05-31 | 3M创新有限公司 | 用于管理入射光的散射的方法和由其产生的制品 |
| CN115665644B (zh) * | 2022-09-29 | 2025-11-28 | 兴科电子(东莞)有限公司 | 一种耳挂式耳机的成型工艺 |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2804410A (en) * | 1953-10-27 | 1957-08-27 | Nat Lead Co | Method for nitriding titanium surfaces |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0468758B1 (de) * | 1990-07-24 | 1997-03-26 | Semiconductor Energy Laboratory Co., Ltd. | Verfahren zum Herstellen isolierender Filme, Kapazitäten und Halbleiteranordnungen |
| US5456599A (en) * | 1992-03-17 | 1995-10-10 | Hamilton Ortho Inc. | Orthodontic arch wires and brackets |
| US5232361A (en) * | 1992-04-06 | 1993-08-03 | Sachdeva Rohit C L | Orthodontic bracket |
| US5334264A (en) * | 1992-06-30 | 1994-08-02 | Board Of Supervisors Of Louisiana State University And Agricultural And Mechanical College | Titanium plasma nitriding intensified by thermionic emission source |
| US5816801A (en) * | 1996-10-02 | 1998-10-06 | Ormco Corporation | Insert for reinforcing an orthodontic appliance and method of making same |
| US6299438B1 (en) * | 1997-09-30 | 2001-10-09 | Implant Sciences Corporation | Orthodontic articles having a low-friction coating |
| US6280185B1 (en) * | 2000-06-16 | 2001-08-28 | 3M Innovative Properties Company | Orthodontic appliance with improved precipitation hardening martensitic alloy |
| US6716444B1 (en) * | 2000-09-28 | 2004-04-06 | Advanced Cardiovascular Systems, Inc. | Barriers for polymer-coated implantable medical devices and methods for making the same |
| US6527938B2 (en) * | 2001-06-21 | 2003-03-04 | Syntheon, Llc | Method for microporous surface modification of implantable metallic medical articles |
| US7507617B2 (en) * | 2003-12-25 | 2009-03-24 | Semiconductor Energy Laboratory Co., Ltd. | Method for manufacturing semiconductor device |
-
2002
- 2002-12-19 FR FR0216265A patent/FR2848810B1/fr not_active Expired - Fee Related
-
2003
- 2003-12-17 AU AU2003302185A patent/AU2003302185A1/en not_active Abandoned
- 2003-12-17 JP JP2004561582A patent/JP2006510426A/ja active Pending
- 2003-12-17 EP EP03809995A patent/EP1573083A2/de not_active Withdrawn
- 2003-12-17 US US10/537,652 patent/US20060204919A1/en not_active Abandoned
- 2003-12-17 WO PCT/FR2003/050183 patent/WO2004056283A2/fr not_active Ceased
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2804410A (en) * | 1953-10-27 | 1957-08-27 | Nat Lead Co | Method for nitriding titanium surfaces |
Also Published As
| Publication number | Publication date |
|---|---|
| US20060204919A1 (en) | 2006-09-14 |
| WO2004056283A3 (fr) | 2004-08-26 |
| FR2848810B1 (fr) | 2005-11-11 |
| AU2003302185A8 (en) | 2004-07-14 |
| AU2003302185A1 (en) | 2004-07-14 |
| WO2004056283A2 (fr) | 2004-07-08 |
| FR2848810A1 (fr) | 2004-06-25 |
| JP2006510426A (ja) | 2006-03-30 |
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Legal Events
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| DAX | Request for extension of the european patent (deleted) | ||
| 17Q | First examination report despatched |
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| RIC1 | Information provided on ipc code assigned before grant |
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