U.S. patent application number 11/894485 was filed with the patent office on 2008-02-07 for dental appliance sequence ordering system and method.
This patent application is currently assigned to Align Technology, Inc.. Invention is credited to Eric Kuo.
Application Number | 20080032248 11/894485 |
Document ID | / |
Family ID | 33435452 |
Filed Date | 2008-02-07 |
United States Patent
Application |
20080032248 |
Kind Code |
A1 |
Kuo; Eric |
February 7, 2008 |
Dental appliance sequence ordering system and method
Abstract
The present invention provides systems and methods for providing
dental appliances, particularly orthodontic appliances, to a
patient wherein the patient is easily able to determine the order
or sequence in which the appliances should be worn. Typically the
appliances are to be worn in a particular sequence to provide
desired treatment, such as a progressive movement of teeth through
a variety of arrangements to a final desired arrangement.
Inventors: |
Kuo; Eric; (Foster City,
CA) |
Correspondence
Address: |
TOWNSEND AND TOWNSEND AND CREW, LLP (018563)
TWO EMBARCADERO CENTER, EIGHTH FLOOR
SAN FRANCISCO
CA
94111-3834
US
|
Assignee: |
Align Technology, Inc.
Santa Clara
CA
|
Family ID: |
33435452 |
Appl. No.: |
11/894485 |
Filed: |
August 20, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10612239 |
Jul 1, 2003 |
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11894485 |
Aug 20, 2007 |
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Current U.S.
Class: |
433/6 |
Current CPC
Class: |
A61C 2202/00 20130101;
A61C 7/08 20130101 |
Class at
Publication: |
433/006 |
International
Class: |
A61C 3/00 20060101
A61C003/00 |
Claims
1. A system of packaged dental appliances comprising: a plurality
of packages each containing a dental appliance having cavities
shaped to receive and resiliently reposition teeth from one
arrangement to a successive arrangement, wherein the plurality of
packages are joined in a continuous chain designating an order in
which each of the dental appliances are to be worn by a patient to
provide dental treatment, and wherein the plurality comprises a
non-numeric, non-alpha-numeric indicia on a package at an end of
the chain, the indicia comprising information indicating a dental
appliance to be worn first.
2. A system as in claim 2, wherein the packages are each joined by
a perforation wherein the packages can be separated by breaking the
perforation.
3. A system as in claim 3, wherein the packages are joined by a
heat seal.
4. A system of packages for dental appliances, comprising: a
plurality of packages, each package of the plurality configured for
housing at least one dental appliance, each of the dental
appliances having cavities shaped to receive and resiliently
reposition teeth from one arrangement to a successive arrangement,
wherein each package includes a label having a non-numeric,
non-alpha-numeric indicia comprising information indicating the
order of usage of the corresponding dental appliance, and wherein a
package includes a non-numeric, non-alpha-numeric indicia
comprising information identifying a first dental appliance in the
order of usage.
5. A system as in claim 4, wherein the label includes a series of
numbers and the non-numeric, non-alpha-numeric indicia comprises a
marking on one of the numbers, wherein the marking indicates order
of usage of the corresponding dental appliance.
6. A system as in claim 4, wherein the label includes a series of
numbers and the non-numeric, non-alpha-numeric indicia comprises a
removal of one of the numbers, wherein the removal indicates order
of usage of the corresponding dental appliance.
7. A system as in claim 6, wherein the removal of one of the
numbers comprises a holepunch.
8. A system as in claim 4, wherein the non-numeric,
non-alpha-numeric indicia comprises at least one shape, wherein the
shape indicates order of usage of the corresponding dental
appliance.
9. A system as in claim 8, wherein the at least one shape comprises
at least one stripe.
10. A system as in claim 9, wherein the at least one stripe
comprises a series of stripes forming a barcode.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 10/612,239 (Attorney Docket No.
018563-006700US), filed Jul. 1, 2003, and related to divisional
U.S. patent application Ser. No. 11/285,707 (Attorney Docket No.
018563-006710US), filed Nov. 21, 2005, the full disclosures of each
of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention is related generally to the field of
orthodontics. More particularly, the present invention is related
to methods and systems for dispensing a series of orthodontic
appliances in a sequence to a patient.
[0004] Repositioning teeth for aesthetic or other reasons is
accomplished conventionally by wearing what are commonly referred
to as "braces." Braces comprise a variety of appliances such as
brackets, archwires, ligatures, and O-rings. Attaching the
appliances to a patient's teeth is a tedious and time consuming
enterprise requiring many meetings with the treating orthodontist.
Consequently, conventional orthodontic treatment limits an
orthodontist's patient capacity and makes orthodontic treatment
quite expensive. Moreover, from the patient's perspective, the use
of braces is unsightly, uncomfortable, presents a risk of
infection, and makes brushing, flossing, and other dental hygiene
procedures difficult.
[0005] As a result, alternative methods and systems for
repositioning teeth have been developed. For example, repositioning
may be accomplished with a system comprising a series of appliances
configured to receive the teeth in a cavity and incrementally
reposition individual teeth in a series of at least three
successive steps. Most often, the methods and systems reposition
teeth in from ten to twenty-five successive steps, although complex
cases involving many of the patient's teeth may take forty or more
steps. The individual appliances are typically comprised of a
polymeric shell having the teeth-receiving cavity formed therein,
typically by molding. The successive use of a number of such
appliances permits each appliance to be configured to move
individual teeth in small increments.
[0006] Typically the systems are planned and all individual
appliances are fabricated at the outset of treatment. Thus, the
appliances may be provided to the patient as a single package or
system. The order in which the appliances are to be used can be
marked by sequential numbering directly on the appliances or on
tags, pouches or other items which are affixed to or which enclose
each appliance so that the patient can place the appliances over
his or her teeth in an order and at a frequency prescribed by the
orthodontist or other treating professional. Successive appliances
will be replaced when the teeth either approach (within a
preselected tolerance) or have reached the target end arrangement
for that stage of treatment, typically being replaced at an
interval in the range from 2 days to 20 days, usually at an
interval in the range from 5 days to 10 days.
[0007] In general, it is preferable to simplify procedures for the
patient to increase patient compliance and reduce patient errors in
carrying out the treatment protocol. Therefore, it is desirable to
utilize a packaging or ordering system which will provide
appliances to a patient in a manner which is clearly discernable to
the patient the order of the appliances. In addition, such
packaging or ordering system should be amenable to mid-treatment
changes to the treatment protocol, possibly adding or eliminating
appliances after the initial set of appliances has been produced
and packaged. At least some of these objectives will be met by the
methods and systems of the present invention described
hereinafter.
[0008] 2. Description of the Background Art
[0009] Tooth positioners for finishing orthodontic treatment are
described by Kesling in the Am. J. Orthod. Oral. Surg. 31:297-304
(1945) and 32:285-293 (1946). The use of silicone positioners for
the comprehensive orthodontic realignment of a patient's teeth is
described in Warunek et al. (1989) J. Clin. Orthod. 23:694-700.
Clear plastic retainers for finishing and maintaining tooth
positions are commercially available from RAINTREE ESSIX, INC., New
Orleans, La. 70125, and TRU-TAIN PLASTICS, Rochester, Minn. 55902.
The manufacture of orthodontic positioners is described in U.S.
Pat. Nos. 5,186,623; 5,059,118; 5,055,039; 5,035,613; 4,856,991;
4,798,534; and 4,755,139.
[0010] Other publications describing the fabrication and use of
dental positioners include Kleemann and Janssen (1996) J. Clin.
Orthodon. 30:673-680; Cureton (1996) J. Clin. Orthodon. 30:390-395;
Chiappon (1980) J. Clin. Orthodon. 14:121-133; Shilliday (1971) Am.
J. Orthodontics 59:596-599; Wells (1970) Am. J. Orthodontics
58:351-366; and Cottingham (1969) Am. J. Orthodontics 55:23-31.
BRIEF SUMMARY OF THE INVENTION
[0011] The present invention provides systems and methods for
providing dental appliances, particularly orthodontic appliances,
to a patient wherein the patient is easily able to determine the
order or sequence in which the appliances should be worn. Typically
the appliances are to be worn in a particular sequence to provide
desired treatment, such as a progressive movement of teeth through
a variety of arrangements to a final desired arrangement.
[0012] In a first aspect of the present invention, a system of
dental appliances is provided comprising a plurality of dental
appliances wherein at least some of the plurality include a
non-numeric indicia designating an order in which each of the at
least some of the plurality are to be worn by a patient to provide
dental treatment. Typically, each of the plurality of dental
appliances comprise a polymeric shell having cavities shaped to
receive and resiliently reposition teeth from one arrangement to a
successive arrangement. Exemplary embodiments of such dental
appliances are described in U.S. Pat. No. 5,975,893, incorporated
herein by reference for all purposes. In some embodiments, each of
the polymeric shells has at least one terminal tooth cavity and the
indicia comprises a terminal tooth cavity of differing length in
each of the polymeric shells. In other embodiments, each of the
polymeric shell has a height and the indicia comprises a different
height in each of the polymeric shells.
[0013] In still other embodiments, the indicia comprises one or
more cutouts so that each polymeric shell has a different cutout
pattern. Sometimes the cutout comprises a notch in an edge of the
appliance.
[0014] In yet other embodiments, the indicia comprises a color
wherein each appliance has different color. The color of the
appliances may have the same hue and vary by intensity, for
example. The color may comprise a dissolvable dye. Or, the system
may further comprise a wrapper removably attachable to each of the
appliances, wherein each wrapper has the color.
[0015] In another aspect of the present invention, a system of
packaged dental appliances is provided comprising a plurality of
packages each containing a dental appliance, wherein the plurality
of packages are joined in a continuous chain designating an order
in which each of the dental appliances are to be worn by a patient
to provide dental treatment. In some instances, the packages are
each joined by a perforation wherein the packages can be separated
by breaking the perforation. In other instances, the packages are
joined by, for example, a heat seal. Further, the system may
include a marking on a package at an end of the chain indicating
the dental appliance to be worn first. Again, each of the plurality
of dental appliances may comprise a polymeric shell having cavities
shaped to receive and resiliently reposition teeth from one
arrangement to a successive arrangement.
[0016] In a further aspect of the present invention, a system of
dental appliances is provided comprising a plurality of dental
appliances to be worn by a patient to provide dental treatment, and
a framework, wherein each of the plurality of dental appliances are
removably attached to a portion of the framework. In some
embodiments, each of the plurality of dental appliances comprise a
polymeric shell having cavities shaped to receive and resiliently
reposition teeth from one arrangement to a successive arrangement.
Further, the system may comprise at least one marking on the
framework indicating the order in which the appliances are to be
worn by a patient.
[0017] In still another aspect of the present invention, method of
dispensing dental appliances to a patient is provided. The method
including the step of providing a plurality of packages wherein
each of the packages includes a polymeric shell having cavities
shaped to receive and resiliently reposition teeth from one
arrangement to a successive arrangement, the plurality of package
including a first package containing a first shell to be worn by
the patient to reposition the teeth from the one arrangement to the
successive arrangement and a second package containing a second
shell to be worn by the patient to reposition the teeth from the
successive arrangement to another successive arrangement. The
method further including the steps of delivering the first package
to the patient at a designated time through a remote delivery
system, and delivering the second package to the patient at a later
designated time through the remote delivery system. In most
embodiments, the remote delivery system comprises a mail delivery
system.
[0018] In another aspect of the present invention, a method is
provided of dispensing dental appliances to a patient including
providing a dispenser including a plurality of dental appliances,
wherein each of the appliances comprises a polymeric shell having
cavities shaped to receive and resiliently reposition teeth from
one arrangement to a successive arrangement, the plurality of
appliances including a first shell to be worn by the patient to
reposition the teeth from the one arrangement to the successive
arrangement and a second shell to be worn by the patient to
reposition the teeth from the successive arrangement to another
successive arrangement, and removing the first shell from the
dispenser wherein removal of the first shell dispenses the second
shell.
[0019] In a further aspect of the present invention, a method of
dispensing dental appliances to a patient is provided including
providing a dispenser including a plurality of dental appliances,
wherein each of the appliances comprises a polymeric shell having
cavities shaped to receive and resiliently reposition teeth from
one arrangement to a successive arrangement, the plurality of
appliances including a first shell to be worn by the patient to
reposition the teeth from the one arrangement to the successive
arrangement and a second shell to be worn by the patient to
reposition the teeth from the successive arrangement to another
successive arrangement. The method further includes removing the
first shell from the dispenser, and actuating an actuator that
subsequently dispenses the second shell. In most embodiments, the
actuator comprises a lever, knob, or button.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 is a schematic illustration of a series of appliances
dispensed in a chain.
[0021] FIG. 2 illustrates a series of appliances disposed on a
framework.
[0022] FIG. 3 illustrates a series of appliances provided to a
patient in a dispenser.
[0023] FIGS. 4A-4B illustrate a change in length of a terminal
tooth cavity between appliances in a series.
[0024] FIGS. 5A-5B illustrate a change in height between appliances
in a series.
[0025] FIGS. 6A-6B illustrate the addition of cutouts in each
appliance to indicate an order.
[0026] FIGS. 7A-7C illustrate a change in color to indicate an
order.
[0027] FIG. 8 illustrate an embodiment of a method of delivering
appliances in a desired order.
[0028] FIG. 9 illustrates an appliance which includes a readable
element embedded in the appliance.
[0029] FIG. 10 illustrates a series of packages 12, each having a
label which includes at least one non-numeric indicia.
[0030] FIG. 11 illustrates a package of dental appliances of the
present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0031] It may be appreciated that the orthodontic appliances may be
dispensed to the patient in its entirety, in groups or
individually. Providing the patient with the entire series at the
outset of treatment may be desirable if the treatment plan is
relatively short, the patient is particularly compliant, or it is
particularly convenient, to name a few. In this case, the series
should be ordered so that the patient can easily selected the next
appliance in the sequence when needed. Such ordering may be
designated through packaging or the appliance itself. In some
situations, the patient may receive additional appliances during
the treatment protocol for inclusion in the sequence and/or the
patient may receive instructions to eliminate some of the original
appliances from the treatment protocol. Therefore, such ordering
should allow easy incorporation of additional appliances or
deletion of appliances.
[0032] Alternatively, the patient may be provided with a subset of
the entire series, such as the first ten appliances. In this case,
the subset should be ordered so that the patient can easily
selected the next appliance in the sequence when needed. Again,
such ordering may be designated through packaging or the appliance
itself. The patient may receive additional appliances during the
use of the subset for inclusion in the sequence and/or the patient
may receive instructions to eliminate some of the original
appliances from the subset. Alternatively, the next subset of
appliances may differ from that which was initial determined at the
outset of the treatment protocol. Therefore, such ordering should
allow easy incorporation of additional appliances or deletion of
appliances within or between subsets.
[0033] Further, the patient may be provided with individual
appliances in the order in which they should be used. In this case,
the appliances should be ordered so that the patient can easily
differentiate the appliance they are receiving from the appliances
already received. Again, such ordering may be designated through
packaging or the appliance itself. In addition, such ordering
should allow the appliances to be stored and distributed to the
patient in the correct sequence with minimal attention from the
orthodontic practitioner.
[0034] A variety of embodiments of ordering systems and methods
will be described. In a first embodiment, a series of appliances
are dispensed to the patient in a continuous chain, wherein the
appliances are to be used in the sequence of the chain. An example
of such a chain is schematically illustrated in FIG. 1. Here, each
appliance 10 is disposed within a package 12, wherein the packages
12 are joined together in a continuous chain. In this embodiment,
each package 12 is separable at a perforation 14 from the remaining
packages 12 in the chain. It may be appreciated that the packages
may be joined and/or are separable in any suitable manner including
with the use of adhesives, heat sealing, ultrasonic welding,
linkages or simply indications where to cut, break or separate, to
name a few. To indicate the end of the chain in which it begin use,
a marking may be located on the package 12 or on the appliance 10.
For example, a colored marking 16 may be located on an end package
12a, as shown. This would indicate that a first appliance 10a is
enclosed. Once the first appliance 10a has been removed from the
package 12a and worn for a given amount of time, the patient may
then open a next package 12b in the chain and remove a second
appliance 10b for wearing. This may be repeated throughout the
chain.
[0035] In another embodiment, illustrated in FIG. 2, a series of
appliances 10 are disposed on a framework 20, such as a sprue.
Sprues typically secure objects, such as molded objects, before
their first use. The appliances 10 are secured to the framework 20
in any suitable manner. The appliances 10 are then removed from the
framework 20 according to a treatment protocol. For example, the
first appliance 10a to be used may be disposed at one end of the
framework 20, the second appliance 10b disposed next to the first
appliance 10a, the sequence continuing along the framework 20.
Alternatively or in addition, markings may be disposed on the
framework 20 or the appliances 10 themselves indicating an ordering
of use.
[0036] In another embodiment, illustrated in FIG. 3, a series of
appliances 10 are provided to a patient in a dispenser 30. The
dispenser 30 dispenses the appliances 10 in the order to be used.
Each appliance 10 may be individually dispensed, as shown, or each
appliance 10 may be contained in a package wherein the packages are
individually dispensed. The dispenser 30 may include an actuator
32, such as a lever, button, switch, etc, so that actuation of the
actuator 32 dispenses the appliance 10 or package containing the
appliance 10. Alternatively, removal of an appliance 10 from the
dispenser 30 may actuate dispensing of the next appliance 10. In
this way, the patient is systematically dispensed appliances in a
predetermined order of use.
[0037] In some situations it may be desired to specifically mark
the appliances themselves. Such markings ensure that ordering of
the appliances is distinguishable after removal of the appliances
from any packaging and during use. For example, a portion of each
appliance may be changed to indicate a sequence or order. FIGS.
4A-4B illustrate a change in length of the appliance 10 by changing
the length of a terminal tooth cavity 40. A terminal tooth cavity
40 is one of the last teeth in the appliance. FIG. 4A illustrates a
first appliance 10a wherein a marked terminal tooth cavity 40a has
a given length. FIG. 4B illustrates a second appliance 10b wherein
a marked terminal tooth cavity 40b has a length which differs from
the first appliance 10a. Here, the marked terminal tooth cavity 40b
has a shorter length. The lengths can continue to differ throughout
the sequence of appliances. Alternatively or in addition, the
lengths of other terminal teeth may differ.
[0038] FIGS. 5A-5B illustrate a change in the height of each
appliance 10 to indicate a sequence or order. The height of the
appliance 10 is the distance from the occlusal surfaces 46 to the
edges 48 of the appliance 10. FIG. 5A illustrates a first appliance
10a having a given height. FIG. 5B illustrates a second appliance
10b having a height which differs from the first appliance 10a.
Here, the second appliance 10b has a shorter height. The heights
can continue to differ throughout the sequence of appliances
indicating an order. It may be appreciate that the overall height
of the appliance may differ or the height of specific portions of
the appliance may differ through the sequence.
[0039] FIGS. 6A-6B illustrate the addition of notches or cutouts 56
in each appliance 10 to indicate a sequence or order. The cut outs
may be of any size, shape, orientation, or number forming any
pattern. Further, the cut outs may be located on an edge 48 of the
appliance 10 or on any surface, including an occlusal surface 46.
FIG. 6A illustrates a first appliance 10a having a first cut out
56a. The first cut out 56a has a rectangular shape and is located
near an edge 48. FIG. 5B illustrates a second appliance 10b having
a second cut out 56b so that the cut out pattern of the first
appliance 10a differs from that of the second appliance 10b. Here,
the second cut out 56b also has a rectangular shape and is located
near the edge 48 adjacent to the first cut out 56a. The cut out
patterns can continue to differ throughout the sequence of
appliances indicating an order.
[0040] FIGS. 7A-7C illustrate a change in color, such as a hue,
gradation of hues, shade, tint or intensity, for each appliance 10
to indicate a sequence or order. For example, the appliances 10 may
appear darker or lighter in color through the series, such as
ranging from dark red to light pink or vice versa. Or, the sequence
may follow the color of the rainbow, such as red, orange, yellow,
green, etc. Or, the sequence may follow any other prescribed order
of colors. FIG. 7A illustrates a first appliance 10a having a first
color 60a. FIG. 7B illustrates a second appliance 10b having a
second color 60b so that the color of the first appliance 10a
differs from that of the second appliance 10b. The color changes
can continue to differ throughout the sequence of appliances
indicating an order. It may be appreciated that the appliances 10a,
10b may have the color over their entirety, as shown, or the
appliances may be colored in some areas and not in others. Or
multiple colors may be used on a single appliance, such as in
stripes, blocks or various shapes. The color may be embedded in the
appliance, such as with the use of a colored plastic rather than
the typical clear plastic. Or, the color may be in the form of a
dissolvable dye which dissolves in contact with air, such as upon
removal from a package, or contact with liquid, such as when rinsed
with water or placed in the patient's mouth. Alternatively, as
illustrated in FIG. 7C, the color may be present in a peel-away
wrapper 62. The colored wrapper 62 may be attached to the appliance
10 by lamination or other methods. In this example, the wrapper 62
covers the occlusal surfaces 46 of the appliance 10, however any
portion of the appliance 10 may be covered. When the appliance 10
is to be used, the wrapper 62 is peeled away, as shown, and
removed. In this way, the appliances may be ordered by color but
worn in a transparent state.
[0041] Alternatively or in addition, the patient may be provided
with individual appliances in the order in which they should be
used. To provide such ordering while allowing the appliances to be
stored and distributed to the patient in the correct sequence with
minimal attention from the orthodontic practitioner, a method may
be used in which the appliances are delivered by mail in a specific
sequence. FIG. 8 illustrates an embodiment of such a method. As
shown, the appliances 10 are individually packaged so that a first
package 80 contains a first appliance, a second package 82 contains
a second appliance, a third package 84 contains a third appliance,
etc. The packages 80, 82, 84 are sent through the mail or any
delivery system so that they are delivered to the patient P
according to a desired schedule. For example, the first package 80
is delivered to the patient P at day 1, the second package 82 is
delivered at day 7, the third package 84 is delivered at day 14,
etc. It may be appreciated that the individual packages may
alternatively be comprises of series of appliances, such as subsets
of the entire series of the treatment plan. In such a case, the
patient P is delivered a package of appliances 10 at each interval,
wherein each package includes a series of appliances. The series
may itself also be ordered by any given system, including any of
those mentioned above.
[0042] FIG. 9 illustrates one appliance 10 of a series of
appliances wherein the appliance 10 includes a readable element 100
embedded in the appliance 10. Alternatively, the readable element
100 may be affixed to the appliance 10 or to a package enclosing
the appliance. The readable element 100 may comprise a chip, a bar
code or other element that is computer readable, including
identification by wireless means, including radiofrequency (rf)
identification. When a reader 102 passes over the element 100, the
reader 102 translates the information into a word, symbol or other
identifying feature. When translated into a word, the word may
include, "first", "second", "third", or "last" to name a few. Also,
the word may be in any language, including English, Spanish,
French, German, Japanese, etc. The word or identifying feature may
be auditory, such as a recording or generation of a spoken voice,
or visual, such as a print display. Alternatively, the feature may
be transmitted by tactile means, such as by vibration.
[0043] FIG. 10 illustrates a series of packages 12, each package 12
including at least one appliance 10. Affixed to or incorporated in
each package 12 is a label 100. The label 100 includes at least one
non-numeric indicia. For example, a first package 102 shows a label
100 having a series of numbers wherein one number is marked, in
this case stamped with a colored dot 103. This indicates which
appliance 10 the first package 102 contains in the treatment
sequence. It may be appreciated that the number can be marked with
any symbol by any method, including removing the number by erasure,
punch-out or notching. It may also be appreciated that other
symbols may be used other than numbers, wherein one of the symbols
is marked. This is illustrated in a second package 104 which shows
such a label 100. A third package 106 shows a label 100 having a
series of symbols, such as shapes, in this case, triangles 120. The
symbols themselves or the color, number, or arrangement may
indicate which appliance 10 the third package 106 contains in the
treatment series. It may be appreciated that such symbols may
include stripes, as illustrated on a fourth package 108 which shows
such a label 100. The stripes may be human readable or computer
readable, such as a barcode.
[0044] FIG. 11 illustrates an embodiment of a package of dental
appliances comprising a package 12 including a plurality of dental
appliances 10 positioned in an arrangement within the package 12
which indicates an order of usage. In this embodiment, the
arrangement comprises stacking of the appliances.
[0045] Although the foregoing invention has been described in some
detail by way of illustration and example, for purposes of clarity
of understanding, it will be obvious that various alternatives,
modifications and equivalents may be used and the above description
should not be taken as limiting in scope of the invention which is
defined by the appended claims.
* * * * *