Orthodontic archwires are packaged between pairs of flexible sheets that are releasably fixed to each other. The archwires are spaced apart from each other between the sheets and arranged in a nested array wherein a portion of one archwire is received within the U-shaped configuration of another archwire. Lines of weakness extend between adjacent pairs of the archwires for enabling detachment of one archwire from remaining archwires of the assembly when desired.

CROSS-REFERENCE TO RELATED APPLICATION 
This application claims priority to Provisional U.S. patent application 
Ser. No. 60/001,039 filed Jun. 28, 1995. 
BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to an assembly of an orthodontic archwire and a 
package initially covering and protecting the archwire. 
2. Description of the Related Art 
Orthodontic treatment often involves the use of a variety of small 
articles. For example, orthodontic treatment typically includes the use of 
small, slotted appliances known as brackets that are fixed to the teeth of 
the patient's upper and lower dental arch. An archwire is placed in the 
slot of each bracket, and serves as a track to guide movement of the teeth 
to orthodontically correct positions. In addition, appliances known as 
buccal tubes are often fixed to the molar teeth and serve as an anchor for 
ends of the archwire. 
A variety of different archwires are available, and it is common practice 
for an orthodontist to retain a number of different archwires on hand for 
use when needed. Archwires are available in varying overall sizes to match 
the size of the patient's upper or lower dental arch. In addition, 
archwires may have a round, square or rectangular cross-sectional 
configuration and may be of different cross-sectional sizes in accordance 
with the orthodontist's preferred treatment technique. 
Often, only a single set of brackets is affixed to the patient's teeth 
during the course of treatment. However, the archwire may be changed at 
selected intervals in the treatment program and replaced with another 
archwire having somewhat different characteristics. For example, an 
archwire having a relatively low stiffness may be used initially when the 
teeth are located some distance from their intended final position so that 
undue and possible painful forces are not experienced by the patient. As 
the teeth move closer to their desired final positions, the archwire can 
be replaced with an archwire having a higher stiffness in order to 
facilitate moving the teeth over the remaining distances. 
Orthodontic archwires are also available in a number of different materials 
and constructions. As examples, archwires are commonly available in a 
number of different alloys, including alloys of stainless steel, alloys of 
nitinol (which principally comprise nickel and titanium, but which may 
also include small amounts of other components such as copper or cobalt) 
and cobalt-based nickel alloys. The archwires may have a square, 
rectangular or circular configuration in transverse cross-section. 
Moreover, the archwires may be made of a solid, unitary section of wire or 
may be made of a number of multiple strands that are braided, twisted or 
wrapped around a core in coaxial fashion. 
A number of packaging systems have been used in the past to store and 
dispense orthodontic archwires. In some instances, a number of identical 
archwires are packaged in a single carton. Unfortunately, such packaging 
may provide an opportunity for remaining archwires in the carton to be 
contaminated whenever the carton is opened to remove a single archwire. 
There has also been increased interest in recent years in unit-of-use 
packaging, wherein a single archwire is packaged in its own container and 
consequently is less likely to be cross-contaminated. In some instances, 
the archwire and the interior of the container have been sterilized by the 
manufacturer. Other containers are not sterilized by the manufacturer, but 
are adapted to be placed in an autoclave by the orthodontist to sterilize 
the container and its contents. 
Many orthodontic archwires have been packaged in pouches. Some pouches are 
reduced-sized versions of well-known plastic sandwich bags that have a 
zipper-type closure on one end. Such pouches sometimes have a printed 
label adhered by a pressure sensitive adhesive to its outer surface. 
Moreover, some pouches have a printed insert that is placed inside the 
pouch next to the appliance. 
Other pouches for orthodontic archwires are made by cutting two panels or 
sheets into a square or rectangular configuration of equal size, and then 
adhering or otherwise joining the sheets together along their periphery to 
enclose an archwire between the sheets. One sheet is made of a flexible 
clear plastic material to facilitate viewing of the packaged archwire. The 
other sheet is often made of a flexible paper or other material having a 
printable surface, so that the manufacturer's name, a description of the 
packaged archwire and other information such as instructions, notices or 
lot numbers may be provided directly on the pouch. 
There is a continuing need in the art to improve packaging for orthodontic 
devices, including orthodontic archwires. In particular, there is a need 
for an improved unit-of-use package which uses less packaging materials 
than conventional packages. Preferably, such an improved package will 
facilitate shipping, storage and dispensing of the archwires so that a 
number of packaged archwires can be handled simultaneously without undue 
effort and without requiring substantial space. Moreover, there is a need 
to improve conventional methods of displaying stored orthodontic 
archwires, so that the proper archwire can be easily stored and yet 
readily selected by the orthodontist when needed. 
SUMMARY OF THE INVENTION 
The present invention concerns a packaged orthodontic archwire assembly 
that comprises a first sheet and a second sheet extending over and 
releasably fixed to the first sheet. A plurality of orthodontic archwires 
are received between the first sheet and the second sheet. Each of the 
archwires has a generally U-shaped configuration and has a pair of spaced 
apart leg portions and a bight portion integrally interconnecting the leg 
portions. The archwires are spaced apart from each other and arranged in a 
nested array wherein a portion of one archwire is received within the 
U-shaped configuration of another archwire. At least one of the sheets 
includes one or more lines of weakness extending between adjacent pairs of 
the archwires for enabling detachment of one archwire from remaining 
archwires of the assembly when desired. 
The nested array of archwires substantially reduces the space that might 
otherwise be required for shipping, storage and dispensing of the 
archwires. Yet, each archwire is individually packaged between sections of 
the sheet so that the likelihood of cross-contamination is significantly 
reduced. The assembly is particularly suited for manufacture in automated 
fashion.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
A packaged orthodontic archwire assembly is designated by the numeral 10 in 
FIGS. 1-4. Each assembly includes an upper section with a hole, and in 
FIG. 1 a number of the assemblies 10 are received on a dispensing peg 12 
for storage and dispensing. 
Each assembly 10 includes a first sheet 14 and a second sheet 16 that 
extends over the first sheet 14. An exaggerated cross-section of the 
sheets 14, 16 is shown in FIGS. 3 and 4. 
The first sheet 14 is preferably made of flexible material, and most 
preferably is a clear transparent plastic material such as polyethylene. 
The second sheet 16 is also preferably made of flexible material, and is 
most preferably made of a material having at least one printable surface. 
A suitable material for the second sheet 16 is paper. 
As illustrated in FIG. 3, a layer of cohesive 18 is in contact with the 
first sheet 14, and a layer of cohesive 20 is in contact with the second 
sheet 16. The layers of cohesive 18, 20 adhere to themselves and also to 
their respective underlying sheets 14, 16, but do not strongly adhere to 
other materials such as orthodontic archwires. Suitable cohesive materials 
include latex-based materials. 
A suitable plastic sheet and cohesive assembly for the sheet 14 end the 
cohesive 18 is known as cold-seal sterile packaging, anchor web (cling 
free film); no. RC4101 from Phoenix Health Care Products. A suitable paper 
sheet and cohesive assembly for the sheet 16 and the cohesive 20 is known 
as cold-seal sterile packaging, transfer web (35-40 lb/ream paper); no. 
D1102 from Phoenix Health Care Products. 
As shown in FIGS. 1 and 2, a plurality of orthodontic archwires 22 are 
received between the first sheet 14 end the second sheet 16. Each of the 
archwires 22 has a pair of spaced apart leg portions 24 and a bight 
portion 26 integrally interconnecting the leg portions 24. The archwires 
22 have a concave or generally U-shaped configuration. The leg portions 24 
may be parallel to each other, or diverge at an acute angle away from each 
other as the free ends of the leg portions 24 are approached. 
The archwires 22 are spaced apart an equal distance from adjacent 
archwires, and are arranged in a nested array. In the array shown in FIGS. 
1 and 2, each archwire 22 is oriented in essentially the same direction 
and is parallel to the remaining archwires 22 of the assembly 10. 
The archwires 22 may have any one of a number of cross-sectional 
configurations such as round, rectangular or square. The archwires 22 may 
be made of various alloys of stainless steel, nickel-titanium or other 
materials such as are known in the art and may be solid or made from a 
number of twisted or braided filaments. Suitable archwires are sold under 
the brands names NITINOL XL, NITINOL SE and HI-T, from 3M Unitek. 
A line of weakness 28 extends in the sheets 14, 16 between each adjacent 
pair or archwires 22 as shown in FIGS. 1 and 2 and has a concave or 
generally U-shaped configuration somewhat similar to the configuration of 
the archwires 22. The lines of weakness 28 are made of a series of spaced 
apart perforations or are made by cutting or indenting one or both of the 
sheets 14, 16 to a controlled depth. The lines of weakness 28 define 
separate sections surrounding each archwire 22 of the assembly 10, and 
each section includes a portion of the first and second sheet 14, 16. 
Examples of the sections are designated by the numerals 30 and 32 in FIG. 
2. 
The sections of the assembly 10 can be pulled apart from each other when it 
is desired to dispense and use an archwire 22. For example, the section 32 
as shown in FIG. 2 has been detached from the section 30 as well as the 
remaining sections of the assembly 10. The sheets 14, 16 preferably 
include notches 34 located at both ends of each line of weakness 28 in 
order to facilitate rupturing the assembly 10 along the selected line of 
weakness 28 when desired. 
Preferably, each of the sheets 14, 16 includes a series of side pull tabs 
36 that are each associated with a single, corresponding section. The 
cohesive associated with the pull tabs 36 is masked to facilitate grasping 
and separation of the pull tabs 36. Alternatively, the pull tabs 36 lack a 
layer of cohesive to facilitate grasping and separation. Once the pair of 
pull tabs 36 of one section of the assembly 10 have been grasped by 
separate hands, the pull tabs 36 are pulled away from each other to 
release the first sheet 14 from the second sheet 16. 
Typically, the chosen section will be detached from remaining sections 
along the corresponding line of weakness 28 before the pull tabs 36 are 
used to open that section. As an option, the pull tab 36 of the first 
sheet may be of a different length in a horizontal direction viewing FIGS. 
1 and 2 than the pull tab of the second sheet 16 in order to facilitate 
grasping of the sheets 14, 16 by separate hands. 
As the pull tabs 36 are lifted apart from each other, one of the layers of 
cohesive 18, 20 lifts from its adjacent, respective sheet 14, 16 and 
instead adheres to the other layer of cohesive 18, 20 as shown in FIG. 4. 
After the sheets 14, 16 are substantially separated from each other, the 
archwire 22 can be readily grasped by a tool or by hand, and then 
separated from any remaining portion of the sheets 14, 16 and used as 
desired. Advantageously, after one of the layers of cohesive 18, 20 
detaches from its original, adjacent sheet 14, 16, such layer will 
generally not re-adhere to such sheet and thereby provide a tamper evident 
indication that the section has been opened. 
The embodiment of the invention that is illustrated in FIG. 5 concerns an 
assembly 10a that is similar in many respects to the assembly 10 shown in 
FIGS. 1-4. The assembly 10a includes a first sheet, a second sheet 
extending over the first sheet and a series of archwires 22a received 
between the first sheet and the second sheet. The first sheet and the 
second sheet are made of the same materials described in connection with 
the first sheet 14 and the second sheet 16 described above. In addition, 
the first sheet and the second sheet are each coated with a layer of 
cohesive that is similar to the layers of cohesive 18, 20 described above. 
Likewise, the archwires 22a are similar in shape and materials of 
construction to the archwires 22 described above. However, the archwires 
22a are arranged in a somewhat different nested array. In FIG. 5, the leg 
portions 24a of each archwire 22a extend into the concavity and toward the 
bight portion 26a of the next adjacent archwire. As such, two leg portions 
24a of different archwires 22a are received within the U-shaped 
configuration of a third archwire 22a. 
The assembly 10a also includes lines of weakness 28a that are similar in 
construction to the lines of weakness 28 described above. However, the 
lines of weakness 28a have a somewhat different configuration to match the 
nested array of archwires 22a. The lines of weakness 28a, like the lines 
of weakness 28, enable sections of the assembly 10a (such as section 30a) 
to be detached from the next adjacent section (such as section 32a) when 
desired. 
The assembly 10a optionally includes notches (not shown) similar to notches 
34 to facilitate rupture along the lines of weakness 28a. Further, outer 
edge portions 35a along each side of the assembly 10a lack cohesive and 
thereby function as easy-to-grasp pull tabs similar to the pull tabs 36. 
A method of manufacturing the packaged orthodontic archwire assembly 
according to the invention is depicted in FIG. 6. The method includes the 
use of a roll 40 of a clear plastic web (such as polyethylene) that is 
coated with a cohesive and a roll 42 of a paper web that is coated with 
cohesive. The plastic and paper webs advance around respective pressure 
rollers 44, 46 in such a manner that the cohesive layer of one web 
contacts the cohesive layer of the other web as the webs meet at the nip 
between the rollers 44, 46. 
A transport table 50 includes a conveyor for moving a series of spaced 
apart, individual archwires 22 toward the nip between the pressure rollers 
44, 46 as the webs continue to advance. The archwires 22 are thereby 
inserted between the webs. The assembly of the webs and the archwire then 
advance to a perforation roller 54 that provides lines of weakness such as 
lines of weakness 28 or 28a in one or more of the webs. As an alternative, 
the perforation roller 54 can instead be a controlled depth cut rotary die 
that provides the lines of weakness. An anvil 56 roller is located 
directly beneath the roller 54 to provide support for the perforation or 
cutting operation. 
At appropriate intervals of time, advancement of the archwires 22 along the 
transport table 50 is interrupted so that certain adjacent pairs of 
archwires are not nested with each other but instead are spaced relatively 
far apart from each other. When such certain pairs move past the 
perforation roller 54, a cutting knife (not shown) severs the webs in the 
relatively large space between such certain pairs to provide a completed 
packaged archwire assembly similar to that shown in FIGS. 1, 2 or 5 that 
is ready for stock or shipment. 
A variety of methods are available for printing identifying text on the 
packaged archwire sections such as the manufacturer's name, the identity 
of the archwire by size, material, shape or other characteristics, 
cautionary notices and lot numbers. The printed information can be 
pre-printed on the paper web. Alternatively, a printer can be located next 
to the paper web as it advances. Another alternative involves the use of a 
labeler which prints and attaches a pressure sensitive adhesive label to 
one or more sides of the completed archwire assembly as the assembly 
advances.