U.S. patent application number 09/268185 was filed with the patent office on 2002-02-14 for shapes for tooth whitening strips.
Invention is credited to PROCTOR, LISA RAE, SAGEL, PAUL ALBERT.
Application Number | 20020018754 09/268185 |
Document ID | / |
Family ID | 23021843 |
Filed Date | 2002-02-14 |
United States Patent
Application |
20020018754 |
Kind Code |
A1 |
SAGEL, PAUL ALBERT ; et
al. |
February 14, 2002 |
SHAPES FOR TOOTH WHITENING STRIPS
Abstract
The present invention relates to a tooth whitening strip of
material having a shape adapted to fit a user's teeth. Each user
has four front teeth, two canine teeth and additional back teeth,
such as molars. Each tooth has a front side, a tip, and a back
side. The strip of material is of a shape so that the strip will
substantially cover the front side of at least the user's front
four teeth and two canine teeth. The front sides of additional
teeth may be covered. The tooth whitening strip will then fold over
the tips and onto the back side of one or more of the front four
teeth. However, the strip of material will not cover the tips of
the two canine teeth. The strip of material may be of any shape
that allows for the canines to protrude. Possible shapes include
substantially trapezoidal with or without stair stepped sides or
notches, and rectangular with notches, stair stepped sides, or
recesses.
Inventors: |
SAGEL, PAUL ALBERT; (MASON,
OH) ; PROCTOR, LISA RAE; (FAIRFIELD, OH) |
Correspondence
Address: |
THE PROCTER & GAMBLE COMPANY
PATENT DIVISION
HEALTH CARE RESEARCH CENTER
8340 MASON-MONTGOMERY ROAD
MASON
OH
45040
US
|
Family ID: |
23021843 |
Appl. No.: |
09/268185 |
Filed: |
March 15, 1999 |
Current U.S.
Class: |
424/49 |
Current CPC
Class: |
A61Q 11/00 20130101;
A61C 19/063 20130101; A61K 8/42 20130101; A61K 6/30 20200101; A61K
8/22 20130101; A61K 8/0208 20130101; A61C 19/066 20130101; A61K
8/20 20130101; A61K 8/731 20130101; A61K 8/8147 20130101; A61K 6/30
20200101; C08L 39/06 20130101; A61K 6/30 20200101; C08L 23/06
20130101; A61K 6/30 20200101; C08L 23/0853 20130101; A61K 6/30
20200101; C08L 67/02 20130101; A61K 6/30 20200101; C08L 33/08
20130101; A61K 6/30 20200101; C08L 1/08 20130101; A61K 6/30
20200101; C08L 71/02 20130101; A61K 6/30 20200101; C08L 39/06
20130101; A61K 6/30 20200101; C08L 23/06 20130101; A61K 6/30
20200101; C08L 23/0853 20130101; A61K 6/30 20200101; C08L 67/02
20130101; A61K 6/30 20200101; C08L 33/08 20130101; A61K 6/30
20200101; C08L 1/08 20130101; A61K 6/30 20200101; C08L 71/02
20130101 |
Class at
Publication: |
424/49 |
International
Class: |
A61K 007/16 |
Claims
What is claimed is:
1. A tooth whitening strip of material having a shape adapted to
fit a user's teeth, each of said user's teeth having a front side,
a tip, and a back side and each user having four front teeth, two
canine teeth, and additional back teeth; such that the strip
substantially covers the front side of at least the user's front
four teeth and two canine teeth and is foldable over the tips and
onto the back side of one or more of the front four teeth without
covering the tips of the two canine teeth.
2. The tooth whitening strip according to claim 1, wherein the
strip has a first, second, third, and fourth side, said first and
second sides beings opposing, and said third and fourth sides being
opposing.
3. The tooth whitening strip according to claim 2 wherein the third
side is concave and the fourth side is convex.
4. The tooth whitening strip according to claim 2 wherein the third
side is shorter then the fourth side.
5. The tooth whitening strip according to claim 4 wherein the first
and second sides are stair stepped.
6. The tooth whitening strip according to claim 3 wherein the first
and second sides have recesses causing the third side to be shorter
than the fourth side.
7. The tooth whitening strip according to claim 1 wherein the shape
of the strip is substantially trapezoidal.
8. The tooth whitening strip according to claim 1 wherein the strip
has at least two recesses which prevent the strip from covering the
tips of the two canine teeth.
9. The tooth whitening strip according to claim 1 wherein the strip
has at least two holes or slits which prevent the strip from
covering the tips of the two canine teeth.
10. The tooth whitening strip according to claim 9 wherein the
slits are cross-slits.
11. The tooth whitening strip according to claim 1 wherein the
shape of the strip has rounded corners.
12. The tooth whitening strip according to claim 2 wherein the
strip comprises a fold line from the first side to the second side
such than when the strip is placed on the user's teeth, the fold
line corresponds to the tips of the teeth.
13. The tooth whitening strip according to claim 12 wherein the
user's teeth further comprises an upper and a lower set of teeth,
and said fold line is up to about 0.1 cm to about 4 cm in length
when the user applies the strip to the lower set of teeth.
14. The tooth whitening strip according to claim 12 wherein the
user's teeth further comprises an upper and a lower set of teeth,
and said fold line is up to about 4.3 cm in length when the user
applies the strip to the upper set of teeth.
15. The tooth whitening strip according to claim 1 wherein the
strip is comprised of a flexible material having a sufficient
flexibility to form a curved shape and being readily conformable to
tooth surfaces and to interstitial tooth spaces without permanent
deformation when placed against the teeth.
16. The tooth whitening strip according to claim 1 wherein the
strip is substantially unnoticeable by others when worn.
17. The tooth whitening strip according to claim 1 wherein the
strip is applied to adjoining soft tissue of the teeth in addition
to the teeth.
18. The tooth whitening strip according to claim 1 wherein the
strip has shallow pockets on a substance-coated side of said strip
of material, said shallow pockets having a substance located
therein.
19. The tooth whitening strip according to claim 15 wherein the
strip is a polyethylene film having a nominal film thickness of
less than about 0.1 mm.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to improved shapes of a strip
for a tooth whitening delivery system. The delivery system
comprises a strip of material and tooth whitening substance.
BACKGROUND OF THE INVENTION
[0002] Tooth whitening has become popular in today's culture. More
and more consumers are searching for the best method to achieve
tooth whitening. Professional tooth bleach by a dentist is common.
Generally, there are two types of professional tooth bleaching: in
the dentist's office or outside of the dentist's office. In the
office tooth bleaching generally involves several visits to the
dentist and the use of a rubber dam to protect the patient's gums
from the bleaching agents. Out of the office tooth bleaching
generally involves the use of a device or tray which is made in the
dental office to fit the patient's teeth. The device is reused, and
therefore, must be sufficiently robust to endure repeat handling,
cleaning, filling, installation, and wearing. Typically, a patient
uses the device in time periods when social contact can be
avoided.
[0003] There are now non-professional programs available to persons
interested in whitening their teeth using commercial products
available at drug stores. The commercial products provide a kit
which includes a generic appliance and a container of bleaching
gel. The obvious appeal is the lower cost of the program. A major
disadvantage of this generic "one size fits all" appliance is the
greater void space between the interior walls of the appliance and
the teeth versus a professionally fitted appliance. Hence, in order
to insure intimate contact of the bleaching gel and the teeth
surfaces, more bleaching gel is required. Furthermore, the poorer
fit means a greater loss of bleaching gel onto the gums, into the
oral cavity, and eventual ingestion. The commercial kits, an the
outside-the-office professionally administered program, require the
user to clean and to reuse the appliance. Since generic appliances
are not fitted to the individual user, they are even more bulky in
the mouth than the fitted appliances and thus they restrict social
discourse to a greater degree.
[0004] One attempt to remedy some of the problems of the commercial
kits is disclosed in U.S. Pat. No. 5,575,654, issued to Fontenot on
Nov. 19, 1996. Fontenot discloses a prepackaged moldable dental
appliance adapted to fit a wide range of variously sized dental
arches. In use, the dental appliance is removed from the packaging,
aligned in a parallel fashion to the edges of the teeth and pushed
over the teeth in the direction of the periodontal tissue until it
covers the teeth surfaces.
[0005] Another solution is disclosed in U.S. Pat. No. 5,310,563,
issued to Curtis et al. on May 10, 1994. Curtis et al. disclose a
putty-like material which is formed by pressing against the teeth.
It is held in place by mechanical engagement with undercut surfaces
and by friction. The composition encapsulates the active.
[0006] Other methods are disclosed in U.S. Pat. No. 5,425,953,
issued to Sintov et al. on Jun. 20, 1995. Sintov et al. discloses a
liquid polymer composition for bleaching of the teeth. The liquid
polymer composition forms a film after applied to the teeth. Other
references which disclose using a film in the oral cavity include
U.S. Pat. No. 4,713,243 issued to Schiraldi et al. on Dec. 15,
1987, and U.S. Pat. No. 2,835,628, issued to Saffir on May 20,
1958.
[0007] It is generally assumed that each user or patient will have
four front teeth, two canine teeth, and additional back teeth, such
as molars. This applies to both a user's top set of teeth and the
bottom set of teeth. The shape of the front four teeth and the
canine teeth is generally the same on the top and bottom with the
top set generally being larger. Each of the teeth has a front side,
a back side, and a tip. The front side of the tooth is described as
the side of the tooth that is visible to others and faces the lips
of the mouth. The back side of the tooth is generally not visible
to others unless the mouth is open wide. The tip of the tooth is
defined as the portion of the tooth that is farthest from the gums.
The tip may alternatively be described as the crown, the peak, the
point, or the tops of the tooth. The tips of the front four teeth
are very different is shape as the tips of the canines or back
teeth. The front four teeth are generally flat in shape which
allows for a tooth whitening strip to easily fold over the tips of
the teeth. The tip of the canine teeth generally come to a point or
a cone shape. This shape is not conducive to a strip folding over
or wrapping over the tip. A user of a strip of material covering
the tip of the canines may find that the strip cannot easily
conform and therefore does not stay in place for extended periods
of time. Additionally, it is not as easy for a user to place the
strip of material over the top of the canines. The strip may also
tear at the tip of the canine. In general, it is also preferred
that the strip of material not fold over or wrap over the molars.
The tips of the molars are generally square in shape and do not
allow for a strip to easily fold over the tooth. However, depending
upon the shape of the strip of material, folding over the top of
the molars may be suitable.
[0008] What is needed is a low cost commercial tooth whitening
strip, which has a superior shape and which is in conformable
contact with the appropriate tooth surfaces and will stay in place
during normal daily activities. In addition a tooth whitening strip
shape is needed which does not require extensive user placement
manipulation to be certain of good contact. Furthermore, what is
needed is a non-bulky active containment means that will permit the
wearer to use the system during social discourse without
interfering with the wearer's speech or appearance.
[0009] In patent application U.S. Ser. No. 09/040,000 and U.S. Pat.
No. 5,879,691 there is disclosed a tooth whitening system. The
system comprises a strip of flexible material and a tooth whitening
substance. The shape of the strip was described as any shape that
has rounded corners. The disclosures focused on the characteristics
of the strip such as the flexural stiffness, the materials
comprising the strip, the drape, and the interaction between the
strip and the tooth whitening substance to hold the strip in place.
The present inventors have now discovered that the shape of the
tooth whitening strip is also important. Superior shapes of the
tooth whitening strip allow for better adhesion of the tooth
whitening strip and substance to the teeth. The improved shapes
allow for the tooth whitening strips to remain on a user's teeth
for an even longer amount of time without slipping. Additionally,
the new shapes make the strips less noticeable by the users.
SUMMARY OF THE INVENTION
[0010] The present invention relates to a tooth whitening strip of
material having a shape adapted to fit a user's teeth. Each user
has four front teeth, two canine teeth and additional back teeth,
such as molars. Each tooth has a front side, a tip, and a back
side. The strip of material is of a shape so that the strip will
substantially cover the front side of at least the user's front
four teeth and two canine teeth. The front sides of additional
teeth may be covered. The tooth whitening strip will then fold over
the tips and onto the back side of one or more of the front four
teeth. However, the strip of material will not cover the tips of
the two canine teeth. The strip of material may be of any shape
that allows for the canines to protrude. Possible shapes include
substantially trapezoidal with or without stair stepped sides or
notches, and rectangular with notches, stair stepped sides, or
recesses.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] While the specification concludes with claims which
particularly point out and distinctly claim the present invention,
it is believed that the present invention will be better understood
from the following description of preferred embodiments, taken in
conjunction with the accompanying drawings, in which like reference
numerals identify identical elements and wherein:
[0012] FIG. 1 is a planar view of a tooth whitening strip of
material which is substantially trapezoidal in shape;
[0013] FIG. 2 is a planar view of a tooth whitening strip which is
substantially trapezoidal in shape with stair stepped sides;
[0014] FIG. 3 is a planar view of a tooth whitening strip which is
substantially rectangular in shape with stair stepped sides;
[0015] FIG. 4 is a planar view of a tooth whitening strip which is
substantially rectangular in shape with notched sides;
[0016] FIG. 5 is a planar view of a tooth whitening strip which is
rectangular in shape with two slits;
[0017] FIG. 6 is a planar view of a tooth whitening strip which is
rectangular in shape with two cross-slits;
[0018] FIG. 7 is a planar view of a tooth whitening strip which is
rectangular in shape with two holes;
[0019] FIG. 8 is a cross-sectional view of a user's front six
teeth; and
[0020] FIG. 9 is cross-sectional view of a tooth whitening strip
placed upon a user's front six teeth before being folded over the
back sides of the user's teeth.
DETAILED DESCRIPTION OF THE INVENTION
[0021] The abbreviation "cm", as used herein, means centimeter. The
abbreviation "mm", as used herein, means millimeter.
[0022] Referring now to the drawings, and more particularly to FIG.
1, there is shown a first preferred embodiment of the present
invention, which is generally indicated as 10. Embodiment 10
represents a tooth whitening strip which is substantially
trapezoidal in shape. Embodiment 10 has a first side 11 and second
side 12, a third side 13, and a fourth side 14. First side 11 and
second side 12 are straight sides which angle in from the fourth
side 14 to the third side 13. Third side 13 is concave and shorter
then the fourth side 14. The fourth side 14 is convex. The fourth
side 14 will be placed close to the bottom edge of the front side
of a user's bottom set of front teeth. Alternatively, if the strip
is worn on the user's top set of teeth, the fourth side 14 may be
placed along the top part of the front side of a user's top set of
front teeth. A fold line 15 of embodiment 10 extends from first
side 11 to second side 12. The fold line 15 may be located closer
to the third side 13 or the fourth side 14. The fold line 15 will
be determined by the size of the user's teeth and the placement of
the tooth whitening strip on the user's teeth. The third side 13
will be along the back side of a user's teeth after the strip 10 is
folded along the fold line 15.
[0023] As shown in FIG. 2 by embodiment 20, the tooth whitening
strip of material may be substantially trapezoidal in shape with
stair stepped sides. Embodiment 20 has a first side 21, a second
side 22, a third side 23, and a fourth side 24. Third side 23 is
concave and shorter then the fourth side 24. The fourth side 24 is
convex. First side 21 and second side 22 are both stair step sides.
Fold line 15 extends from the corners 26 and 27 of the stair step
in the first side 21 and the second side 22, respectively.
Embodiment 20 can alternatively be described as two substantially
trapezoidal shapes placed on top of one another. The top trapezoid
is formed by the third side 23, the second side 22 from its corner
27 up to the third side 23, the fold line 25, and the first side 21
from its corner 26 up to the third side 23. The bottom trapezoid is
formed by the fold line 25, the second side 22 from its corner 27
down to the fourth side 24, the fourth side 24, and the first side
21 from its corner 26 down to the fourth side 24.
[0024] FIG. 3 illustrates an alternative embodiment 30 of the
present invention. The tooth whitening strip of material may be
substantially rectangular in shape with stair stepped sides.
Embodiment 30 has a first side 31 and second side 32, a third side
33, and a fourth side 34. First side 31 and second side 32 are both
stair step sides. Fold line 35 extends from the corners 36 and 37
of the stair step in the first side 31 and the second side 32,
respectively. Embodiment 30 can also be described as two rectangles
placed on top of one another. The top rectangle is formed by the
third side 33, the second side 32 from its corner 37 up to the
third side 33, the fold line 35, and the first side 31 from its
corner 36 up to the third side 33. This top rectangle may
alternatively be described as a flap which fits over the back sides
of the user's teeth. The bottom rectangle is formed by the fold
line 35, the second side 32 from its corner 37 down to the fourth
side 34, the fourth side 34, and the first side 31 from its corner
36 down to the fourth side 34.
[0025] The fold line 35 will be placed over the tips of a user's
teeth enabling the strip to fold down onto both the front side and
the back side of the user's teeth. The strip will be placed so that
the user's two canine teeth are just outside of corners 36 and 37.
The fourth side 34 will be located close to the bottom edge of the
front side of a user's bottom set of front teeth. Alternatively if
the strip is worn on the user's top set of teeth, the fourth side
34 may be placed along the top part of the front side of a user's
top set of front teeth. The third side 33 will be along the back
side of a user's teeth.
[0026] FIG. 4 details a tooth whitening strip of material
substantially rectangular in shape with notched sides. Embodiment
40 has a first side 41, second side 42, a third side 43, and a
fourth side 44. Third side 43 and fourth side 44 are both
substantially straight sides and the same length. First side 41 and
second side 42 have notches 46 and 47, respectively, which enable
the tips of the canine teeth not to be covered when the strip is
placed on the user's teeth. Fold line 45 extends from notch 46 in
the first side 41 to notch 47 in the second side 42. Notches 46 and
47 as have a sideways V shapes as shown. The notches may be of any
shape including rectangular, semi circles, etc. that allows the
tips of the canine teeth to not be wrapped by embodiment 40.
[0027] Embodiments 50, 60, and 70 are illustrated by FIGS. 5, 6,
and 7 respectively. The tooth whitening strip of material of
embodiments 50, 60, and 70 is substantially rectangular in shape
with rounded corners. Each embodiment contains two recesses which
allow for protrusion of the canine teeth when the tooth whitening
strip is 15 placed on a user's teeth. FIG. 5 illustrates where the
recesses are straight slits 56 and 57. Slits 56 and 57 extend from
the outside edge of embodiment 50 to an interior point. Fold line
55 extends between slits 56 and 57. FIG. 6 shows slits 66 and 67
which are cross-slits. Cross-slits 66 and 67 are located within
embodiment 60. Fold line 65 extends from cross-slit 66 to
cross-slit 67. Embodiment 70 of FIG. 7 illustrates holes 76 and 77
in the strip. Holes 76 and 77 may be of any size that is sufficient
for the tips of the canines to protrude. Fold line 75 extends
between holes 76 and 77.
[0028] FIG. 8 shows corresponding top 81 and front 82 view of a
user's bottom set of the front six teeth. Top view 81 illustrates
the general arched shape found in the front six teeth. The two
canine teeth 83 and 84 are located on opposite sides of the four
front teeth 85. Not shown are additional back teeth, such as
molars, which are located next to each of the canine teeth. Front
view 82 illustrates the general shapes, including the tips, of the
front four teeth 85 and canine teeth 83 and 84.
[0029] FIG. 9 shows front view 82 of a user's front six teeth shown
in FIG. 8 with the tooth whitening strip illustrated by embodiment
20 of FIG. 2. Embodiment 20 is shown placed along the teeth but not
yet folded over the teeth. As illustrated, fourth side 24 is placed
along the bottom portions of the front four teeth 85 and the two
canine teeth 83 and 84. Fold line 25 hits at the tips of the front
four teeth 85 and allows the tips of the canine teeth 83 and 84 to
be exposed. Canine teeth 83 and 84 protrude at the corners 26 and
27 of the stair steps. Third side 23 will subsequently be folded
down onto the back side of the four front teeth 85.
[0030] Tooth Whitening Strip
[0031] The tooth whitening strip may be called a tooth whitening
strip of material, a strip of material, or a strip. The tooth
whitening strip of material will have a shape that is adapted to
fit a user's teeth. It is preferred that the strip substantially
covers the front side of at least a user's front four teeth and two
canine teeth. These teeth are the most visible teeth for most
users. The strip of material may cover the front side of additional
teeth such as the teeth next two the canine teeth. This may be
desired if these teeth are visible to others. By substantially, it
is meant that at least half of the front tooth surface is covered.
The tooth whitening strip may cover all of the front tooth surface
and may also cover portions of the gums adjacent to the teeth.
Generally, the tooth whitening strip will begin coverage at the
point where the surface of the teeth intersect the gums.
[0032] The tooth whitening strip will be foldable over the tips and
onto the back sides of one or more of the front four teeth without
covering the tips of the two canine teeth. The shape of the strip
will allow for canine tips to not be covered. By folding over the
tips it is meant that the strip covers or wraps around the front
side of the tooth over the tip and onto the back side of the tooth.
Depending upon the size of the strip of material, the entire back
side of the tooth including the adjacent gum may be covered or only
a portion of the back side of the tooth.
[0033] The shape of the tooth whitening strip is critical to allow
for coverage of the front side of the canines by not coverage of
the tips. The shape of the strip may be any shape which allows this
to result. The shape of the tooth whitening strip may be of many
shapes. The strip may be substantially trapezoidal in shape. The
term substantially trapezoidal is used to mean any shape having
four general sides where there are two sides which are generally
parallel or arched the same way. This may result when one side is
convex and the opposing side is concave. The arched shape may help
to reduce bunching of the strip and allow the strip to lay smoother
along the surfaces of the teeth. The other two opposing sides will
generally not be parallel. The strip may be substantially
rectangular in shape. This is used generally to mean a shape with
four sides which each of two sides are close to parallel. Parallel
is used broadly to include when sides are arched, not straight, and
generally not perpendicular. Alternatively, the strip may be of any
shape such as round or oval. The strip may also be of a shape with
many numbers of sides. The shape of the strip does not need to be
symmetrical.
[0034] Any of the sides or edges of the strip may be notched, stair
stepped, or arched. By notched it is meant that there is a recess,
indentation, or curve of some type. By stair stepped it is meant
that the side is not straight and may contain one or more stair
steps. The strip may also contain slits, cross-slits, holes,
perforations, or any suitable formation that allows for the canines
to protrude through or be avoided by the strip of material. In
generally, a recess should allow approximately 2 cm for protrusion
of the canines.
[0035] Each strip of material will contain a fold line. The fold
line is defined as the part of the strip where the tips of the
teeth meet the strip when the strip is folded or wrapped over the
tips. This line may be from the point where one recesses, stair
steps, or notch on one side extends into the strip the farthest to
where the other recess, stair step, or notch extends into the strip
the farthest on the opposing side. For example, at the corner of a
stair step or at the point of a notch. The fold line will generally
extend from one side of the strip to another parallel side and
along the longer part of the strip. The fold line may be self
adjusting depending upon the size and shape of the strip. With a
trapezoidal shape strip, the fold line will be determined based
upon the positioning of the strip on a user's teeth. The fold line
is generally up to about 4 cm in length for a strip designed to fit
on a user's bottom set of teeth. There is not a minimum requirement
for the fold line as long as part of the strip folds over the tips
of at least part of one of the front four teeth. Generally, the
fold line will be from about 0.1 cm to about 4 cm, preferably from
about 0.5 cm to about 3.5 cm, more preferably from about 1 cm to
about 3.2 cm, and most preferably from about 2 cm to about 3.1 cm.
For the top set of a user's teeth, the fold line is up to about 4.3
cm in length. The fold line is generally from about 0.1 cm to about
4.3 cm, preferably from about 0.5 cm to about 4 cm, more preferably
from about 1 cm to about 3.5 cm and most preferably from about 2 cm
to about 3.4 cm.
[0036] Preferably, the shape of the strip of material is any shape
that has rounded corners. "Rounded corners" is defined as not
having any sharp angles or points. The conformable strip of
material is preferably of a size that individually fits the row of
teeth desired to be bleached. The size of the strip of material
depends upon many factors, including the number of teeth to be
bleached, the size of the teeth, and personal preference of the
wearer. In general, the length of the strip of material is from
about 2 cm to about 12 cm, preferably from about 3 cm to about 9
cm, and more preferably from about 4 cm to about 6 cm. If the strip
of material is stair stepped on the sides or trapezoidal shaped,
the longer side of the strip of material is generally from about 3
cm to about 12 cm, preferably from about 3.1 to about 10 cm, more
preferably from about 3.5 cm to about 8 cm, and most preferably
from about 4 cm to about 6 cm. The shorter side is from about 0.1
cm to about 12 cm, preferably from about 0.5 cm to about 8 cm, more
preferably from about 1 cm to about 5 cm, and most preferably from
about 1.5 cm to about 3 cm. The width of the strip of material will
also depend upon many factors, including whether or not the strip
of material wraps completely around the teeth and covers part or
all of the front and back surfaces of the tooth. In a general
application, the width of the strip of material is from about 0.5
cm to about 4 cm and preferably from about 1 cm to about 2 cm.
[0037] The strip of material serves as a protective barrier to
substantially prevent saliva contacting the tooth whitening
substance and leaching and/or erosion of the tooth whitening
substance from the surface of the teeth by the wearer's lips,
tongue, and other soft tissue. In order for an active in tooth
whitening substance to act upon the surface of tooth over an
extended period of time, from several minutes to several hours, it
is important to minimize such leaching and/or erosion. The term
"act upon" is herein defined as bringing about a desired change.
For example, if the substance is a tooth whitener, it bleaches
color bodies to bring about whitening.
[0038] The strip of material may comprise materials such as
polymers, natural and synthetic wovens, non-wovens, foil, paper,
rubber, and combinations thereof. The strip of material may be a
single layer of material or a laminate of more than one layer.
Generally, the strip of material is substantially water
impermeable. The material may be any type of polymer that meets the
required flexural rigidity and is compatible with tooth whitening
actives, such as peroxide. The material may comprise a single
polymer or a mixtures of polymers. Suitable polymers include, but
are not limited to, polyethylene, ethylvinylacetate, ethylvinyl
alcohol, polyesters such as Mylar.RTM. manufactured by DuPont,
fluoroplastics such as Teflon.RTM. manufactured by DuPont, and
combinations thereof. Preferably, the material is polyethylene. The
strip of material is generally less than about 1 mm thick,
preferably less than about 0.05 mm thick, and more preferably from
about 0.001 to about 0.03 mm thick. A polyethylene strip of
material is preferably less than about 0.1 mm thick and more
preferably from about 0.005 to about 0.02 mm thick.
[0039] The strip of material may contain shallow pockets. When the
substance is coated on a substance-coated side of strip of
material, additional substance fills shallow pockets to provide
reservoirs of additional substance. Additionally, the shallow
pockets help to provide a texture to the delivery system. The film
will preferably have an array of shallow pockets. Generally, the
shallow pockets are approximately 0.4 mm across and 0.1 mm deep.
When shallow pockets are included in the strip of material and
substances are applied to it in various thicknesses, the overall
thickness of the delivery system is generally less than about 1 mm.
Preferably, the overall thickness is less than about 0.5 mm.
[0040] Flexural stiffness is a material property that is a function
of a combination of strip thickness, width, and material modulus of
elasticity. This test is a method for measuring the rigidity of
polyolefin film and sheeting. It determines the resistance to
flexure of a sample by using a strain gauge affixed to the end of a
horizontal beam. The opposite end of the beam presses across a
strip of the sample to force a portion of the strip into a vertical
groove in a horizontal platform upon which the sample rests. A
microammeter, wired to the strain gauge is calibrated in grams of
deflection force. The rigidity of the sample is read directly from
the microammeter and expressed as grams per centimeter of sample
strip width. In the present invention, the strip of material has a
flexural stiffness of less than about 5 grams/cm as measured on a
Handle-O-Meter, model #211-300, available from Thwing-Albert
Instrument Co. of Philadelphia, Pa., as per test method ASTM
D2923-95. Preferably, the strip of material has a flexural
stiffness less than about 4 grams/cm, more preferably less than
about 3 grams/cm, and most preferably from about 0.1 grams/cm to
about 1 grams/cm. Preferably, the flexural stiffness of the strip
of material is substantially constant and does not significantly
change during normal use. For example, the strip of material does
not need to be hydrated for the strip to achieve the low flexural
stiffness in the above-specified ranges.
[0041] This relatively low stiffness enables the strip of material
to drape over the contoured surfaces of teeth with very little
force being exerted; that is, conformity to the curvature of the
wearer's mouth and gaps between adjacent teeth is maintained
because there is little residual force within strip of material to
cause it to return to its substantially flat shape. The flexibility
of the strip enables the strip of material to contact adjoining
soft tissue over an extended period of time without physical
irritation. The strip of material does not require pressure forming
it against the teeth.
[0042] The strip of material is held in place on a plurality of
adjacent teeth by adhesive attachment provided by the substance.
The viscosity and general tackiness of the substance cause the
strip of material to be adhesively attached to a plurality of
adjacent teeth without substantial slippage under the potential
friction from the lips, tongue, and other soft tissue rubbing
against the strip of material during mouth movements associated
with talking, drinking, etc. However, this adhesion to the teeth is
low enough to allow the delivery system to be easily removed by the
wearer by peeling off the strip of material using one's finger or
fingernail. The delivery system is easily removable from the
surfaces of the teeth without the use of an instrument, a chemical
solvent, or undue friction. Chemical solvents include any organic
solvents commonly used in oral care products such as alcohol and
other safe solvents such as water, which could be used to dilute
the gelling agent. Undue friction is described as any type of
rubbing with one's finger or a soft implement, such as cotton
balls, swabs, or gauze pads.
[0043] A peel force of from about 1 gram to about 50 grams for a
1.5 cm strip width (approximately 17 grams/cm) is all that is
required. Preferably, the peel force is from about 5 grams to about
40 grams and more preferably from about 10 grams to about 30 grams.
The low peel force is desired for consumer handling purposes. The
low peel force is possible because of the non-aggressive nature of
a gel substance. Only when the flexural stiffness of the strip is
low can the adhesion of the substance also be low. The adhesion of
a stiffer strip would have to be greater in proportion to the strip
stiffness in order to prevent the strip from returning to its flat
condition and pulling away from the contoured surface of a
plurality of teeth.
[0044] The strip of material may be formed by several of the film
making processes known in the art. Preferably, a strip of material
made of polyethylene is made by a blown process or a cast process.
Processes, such as extrusion and other processes that do not affect
the flexural rigidity of the strip of material, are also feasible.
Additionally, the substance may be incorporated onto the strip
during the processing of the strip. The substance may be a laminate
on the strip.
[0045] Tooth Whitening Substance
[0046] The tooth whitening substance is a composition, compound, or
mixture capable of influencing or effecting a desired change in
appearance and/or structure of the surface it contacts. Examples of
appearance and structural changes include, but are not necessarily
limited to, whitening, stain bleaching, stain removal, plaque
removal, and tartar removal. Preferably, the active is for the
whitening of the tooth surfaces.
[0047] The tooth whitening substance may be coated on the strip of
material, be applied by the user to the strip of material, or be
applied by the user to their teeth and then apply the strip over
the coated teeth. The amount of substance applied to the strip of
material or teeth will depend upon the size and capacity of the
piece of material, concentration of the active, and the desired
benefit. Generally, less than about 1 gram of substance is
required. Preferably, from about 0.05 grams to about 0.5 grams and
more preferably from about 0.1 gram to about 0.4 grams of the
substance is used. The amount of substance per square cm of
material is less than about 0.2 grams/cm.sup.2, preferably from
about 0.005 to about 0.1 grams/cm.sup.2, and more preferably from
about 0.01 grams/cm.sup.2 to about 0.04 grams/cm.sup.2.
[0048] The substance of the present invention can be in the form of
a viscous liquid, paste, gel, solution, or other suitable form that
can provide sufficient adhesion. Preferably, the substance is in
the form of a gel. The substance will have a viscosity of from
about 200 to about 1,000,000 cps at low shear rates (less than one
1/seconds). Preferably, the viscosity is from about 100,000 to
about 800,000 cps and more preferably from about 400,000 to about
600,000 cps.
[0049] Actives suitable for whitening include any material safe for
use in the oral cavity which provides bleaching or stain removal.
The actives suitable for whitening are selected from the group
consisting of the peroxides, metal chlorites, perborates,
percarbonates, peroxyacids, and combinations thereof. Suitable
peroxide compounds include hydrogen peroxide, calcium peroxide,
carbamide peroxide, and mixtures thereof. Most preferred is
carbamide peroxide. Suitable metal chlorites include calcium
chlorite, barium chlorite, magnesium chlorite, lithium chlorite,
sodium chlorite, and potassium chlorite. Additional whitening
actives may be hypochlorite and chlorine dioxide. The preferred
chlorite is sodium chlorite.
[0050] The tooth whitening active is present in an amount of from
about 0.01% to about 40%, by weight of the substance. If a peroxide
compound is chosen as the active, the peroxide compound should
provide an amount of hydrogen peroxide equivalent of from about
0.1% to about 20%, preferably from about 0.5% to about 10%, and
most preferably from about 1% to about 7%, by weight of the
substance. To deliver this amount of hydrogen peroxide equivalent,
the peroxide compound, such as carbamide peroxide, is generally
present in an amount of from about 0.1% to about 30% and preferably
from about 3% to about 20%, by weight of the substance.
[0051] The actives are generally contained in an aqueous gel. The
gel is a high viscosity matrix formed from gelling agents known in
the art. These gelling agents are safe for oral use, do not readily
dissolve in saliva, and do not react with or inactivate the oral
care compounds incorporated into them. Generally, the gelling agent
is a swellable polymer. Furthermore, the gel formed with these
agents provides sufficient adhesive attachment of the film material
to the targeted area of the mouth. The level of gelling agent to
form the gel composition is from about 0.1% to about 15%,
preferably from about 1% to about 10%, more preferably from about
2% to about 8%, and most preferably from about 4% to about 7%, by
weight of the substance.
[0052] Suitable gelling agents useful in the present invention
include carboxypolymethylene, carboxymethyl cellulose,
carboxypropyl cellulose, poloxamer, carrageenan, Veegum,
carboxyvinyl polymers, and natural gums such as gum karaya, xanthan
gum, Guar gum, gum arabic, gum tragacanth, and mixtures thereof.
The preferable gelling agent for use in the present invention is
carboxypolymethylene, obtained from B. F. Goodrich Company under
the tradename "Carbopol". Particularly preferable Carbopols include
Carbopol 934, 940, 941, 956 and mixtures thereof. Particularly
preferred is Carbopol 956. Carboxypolymethylene is a slightly
acidic vinyl polymer with active carboxyl groups. The normal
concentration of various carboxypolymethylene resins in water,
according to the manufacturer, is below about 2%. However, it has
been found that by preparing supersaturated carboxypolymethylene
compositions having an absolute concentration in the ranges
specified above, suitable high viscosity oral gel compositions may
be prepared.
[0053] The concentrated carboxypolymethylene gels have a number of
important characteristics in addition to high viscosity. Enough
carboxypolymethylene is added to the oral gel compositions beyond
that required to provide high viscosity such that a significant
quantity of saliva or water is required to lower the viscosity to
the point that the composition may be diluted and washed out by
saliva. The concentrated carboxypolymethylene composition also has
a unique tackiness or stickiness which retains and seals the strip
material against the targeted oral cavity surface it is affixed to,
particularly teeth. However, care should be taken to avoid too much
carboxypolymethylene thereby making insertion or withdrawal of the
strip material difficult.
[0054] Water is also present in the gel compositions disclosed
herein. The water, employed in the present invention should,
preferably, be deionized and free of organic impurities. Water
comprises from about 0.1% to 95%, preferably from about 5% to about
90%, and most preferably from about 10% to about 80%, by weight of
the substance. This amount of water includes the free water that is
added plus that amount that is introduced with other materials.
[0055] A pH adjusting agent may also be added to optimize the
storage stability of the gel and to make the substance safe for
oral tissues. These pH adjusting agents, or buffers, can be any
material which is suitable to adjust the pH of the substance.
Suitable materials include sodium bicarbonate, sodium phosphate,
sodium hydroxide, ammonium hydroxide, sodium stannate,
triethanolamine, citric acid, hydrochloric acid, sodium citrate,
and combinations thereof. The pH adjusting agents are added in
sufficient amounts so as to adjust the pH of the gel composition to
about 4.5 to about 11, preferably from about 5 to about 8.5, and
more preferably from about 5.5 to about 7. pH adjusting agents are
generally present in an amount of from about 0.01% to about 15% and
preferably from about 0.05% to about 5%, by weight of the
substance.
[0056] While the gel described above provides sufficient
adhesiveness, additional gelling agents may also be included in the
formula to help the active ingredients adhere to the tissues of the
oral cavity. Suitable agents include both polymers with limited
water solubility as well as polymers lacking water solubility.
These polymers deposit a thin film on both the oral cavity's soft
and hard tissues when saliva combines with the instant composition.
Suitable limited water solubility adhesives include: hydroxy ethyl
or propyl cellulose. Adhesives lacking water solubility include:
ethyl cellulose and polyox resins. Another possible adhesive
suitable for use in the instant composition is polyvinylpyrrolidone
with a molecular weight of about 50,000 to about 300,000. Still
another possible adhesive suitable for use in the instant
composition is a combination of Gantrez and the semisynthetic,
water-soluble polymer carboxymethyl cellulose.
[0057] An additional carrier material may also be added to the
substance. Carrier materials can be humectants. Suitable humectants
include glycerin, sorbitol, polyethylene glycol, propylene glycol,
and other edible polyhydric alcohols. Humectants are generally
present in an amount of from about 10% to about 95%, preferably
from about 20% to about 80%, and more preferably from about 50% to
about 70%, by weight of the substance. In addition to the above
materials of the gel of the present invention, a number of other
components can also be added to the substance. Additional
components include, but are not limited to, flavoring agents,
sweetening agents, xylitol, opacifiers, coloring agents, and
chelants such as ethylenediaminetetraacetic acid. These additional
ingredients can also be used in place of the compounds disclosed
above.
[0058] Release Liner
[0059] The release liner may be formed from any material which
exhibits less affinity for substance than substance exhibits for
itself and for the strip of material. The release liner preferably
comprises a rigid sheet of material such as polyethylene, paper,
polyester, or other material which is then coated with a non-stick
type material. The release liner material may be coated with wax,
silicone, polyester such as Teflon.RTM., fluoropolymers, or other
non-stick type materials. A preferred release liner is
Scotchpak.RTM., produced by 3M. The release liner may be cut to
substantially the same size and shape as the strip of material or
the release liner may be cut larger than the strip of material to
provide a readily accessible means for separating the material from
the strip. The release liner may be formed from a brittle material
which cracks when the strip is flexed or from multiple pieces of
material or a scored piece of material. Alternatively, the release
liner may be in two overlapping pieces such as a typical adhesive
strip bandage type design. A further description of materials
suitable as release agents is found in Kirk-Othmer Encyclopedia of
Chemical Technology, Fourth Edition, Volume 21, pp. 207-218,
incorporated herein by reference.
EXAMPLES
[0060] The strip of material is preferably a 0.009 mm thick piece
of polyethylene film. The film preferably has an array of shallow
pockets, typically 0.4 mm across and 0.1 mm deep. The strip of
material has a flexural stiffness of about 0.6 grams/cm as measured
on a Handle-O-Meter, model #211-300, available from Thwing-Albert
Instrument Co. of Philadelphia, Pa., as per test method ASTM
D2923-95.
[0061] An example of a tooth whitener is a gel described as
follows: Combine 70% glycerin, 5% carboxypolymethylene, 10%
carbamide peroxide, and 15% water adjusted to pH 6.5 with sodium
hydroxide. Mix until homogeneous.
[0062] Additional examples of alternative tooth whitening gel are
described as follows: Combine 8% carboxypolymethylene in
approximately 84% water, add 4% sodium hydroxide and enough sodium
bicarbonate to bring the pH to about 10. Dissolve in 3.75% sodium
chlorite and mix until homogeneous.
[0063] Combine 60% glycerin, 4.5% carboxypolymethylene, and 5%
hydrogen peroxide. Add sodium hydroxide (50% solution) until the pH
is adjusted as desired and then add the remainder as water. Mix
until homogeneous.
[0064] Combine 56% glycerin, 6% carboxypolymethylene, 10% carbamide
peroxide, and 24% water. Add 4% sodium hydroxide (50% solution) to
adjust the pH. Mix until homogeneous.
[0065] Combine 68% glycerin, 6% carboxypolymethylene, 22% carbamide
peroxide, and 4% sodium hydroxide (50% solution). Mix until
homogeneous.
[0066] Combine 25% glycerin, 69.7% water, 2% xanthan gum, 3%
carboxymethylcellulose, and 0.3% carbamide peroxide. Mix until
homogeneous.
[0067] Combine 24% poloxamer, 20% glycerin, 46% polyethylene
glycol, and 10% carbamide peroxide. Mix until homogeneous.
[0068] Commercial tooth whiteners, such as Opalescence and Nu-Pro
Gold, are also operable with the delivery system of the present
invention.
[0069] Method of Use
[0070] In practicing the present invention, a strip of material is
applied by the user to the teeth. The side of the material facing
the teeth is coated with a tooth whitening substance which is
preferably in a viscous state to provide not only the active but
also tackiness between the tooth surfaces and the strip of material
to hold the strip in place for an extended period of time.
Alternatively, the user may apply a tooth whitening substance to
the teeth or to the strip before applying the strip to the teeth.
The strip of material readily conforms to the teeth by lightly
pressing it against the teeth and/or by the wearer gently sucking
through the gaps between the teeth. The strip of material is easily
removed by the wearer by peeling it off. Preferably, each
successive treatment will use a fresh strip of material.
[0071] The tooth surface is not required to be prepared before the
delivery system is applied. For example, the wearer may or may not
choose to brush his teeth or rinse his mouth before applying the
delivery system. The surfaces of the teeth are not required to be
dried or to be excessively wet with saliva or water before the
strip of material is applied.
[0072] Preferably, the strip of material and substances are
substantially transparent so as to be almost unnoticeable when
worn. Thinness of the delivery system enables the higher
temperature inside of the wearer's mouth to conduct heat through
the strip of material to the normally cooler teeth in order to
accelerate the rate of diffusion of the active material into the
surfaces of the teeth.
[0073] Preferably, the wearer applies the delivery system of the
present to the teeth continuously for about 5 minutes to about 120
minutes a day, preferably from about 30 minutes to about 60
minutes. Generally, this is done once a day for about 7 to 28 days.
The amount of time and the number of days are dependent upon
several factors, including the amount of bleaching desired, the
wearer's teeth, and if initial or maintenance bleaching is desired.
The bleaching is done to achieve a whitening benefit of 1-4 shade
guide improvement as measured by VITA LUMIN.RTM. Vacuum Farbskala
Shade Guides, a product of VITA Zahnfabrik, of BadSackingen,
Germany.
[0074] When the wearer removes the strip of material from the
tooth, there may be a residue of substance remaining on the
surface. This residual will not be great, as the tooth whitening
substance has affinity for both the film and for itself. If
residual substance remains, it may be easily removed by brushing or
rinsing.
[0075] While particular embodiments of the present invention have
been illustrated and described, it will be obvious to those skilled
in the art that various changes and modifications may be made
without departing from the spirit and scope of the invention, and
it is intended to cover in the appended claims all such
modifications that are within the scope of the invention.
* * * * *