U.S. patent application number 11/007409 was filed with the patent office on 2005-06-30 for compositions and methods of delivering bleaching agents to teeth.
Invention is credited to Ghosh, Chanchal Kumar, Scott, Douglas Craig.
Application Number | 20050143274 11/007409 |
Document ID | / |
Family ID | 34705105 |
Filed Date | 2005-06-30 |
United States Patent
Application |
20050143274 |
Kind Code |
A1 |
Ghosh, Chanchal Kumar ; et
al. |
June 30, 2005 |
Compositions and methods of delivering bleaching agents to
teeth
Abstract
The present invention relates to compositions and methods of
whitening teeth of a subject in need thereof, by applying a safe
and effective amount of a composition to a plurality of teeth, the
composition comprising: a. a safe and effective amount of a
bleaching agent; b. a safe and effective amount of a water
insoluble solid phase; c. a safe and effective amount of a water
soluble liquid phase; wherein the ratio of the water insoluble
solid phase to the water soluble liquid phase is from about 1:4 to
about 4:1; wherein the composition is applied for a sufficient
period of time to achieve whitening; and wherein in one embodiment
the composition has a Whitening Index of from about 0.5 to about 4.
The composition optionally comprises a hydrophobically modified
polymer. The present invention also relates to a delivery system
comprising the present compositions used with an integral carrier,
e.g. a strip material, dental tray or sponge material.
Inventors: |
Ghosh, Chanchal Kumar; (West
Chester, OH) ; Scott, Douglas Craig; (Loveland,
OH) |
Correspondence
Address: |
THE PROCTER & GAMBLE COMPANY
INTELLECTUAL PROPERTY DIVISION
WINTON HILL TECHNICAL CENTER - BOX 161
6110 CENTER HILL AVENUE
CINCINNATI
OH
45224
US
|
Family ID: |
34705105 |
Appl. No.: |
11/007409 |
Filed: |
December 8, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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60530387 |
Dec 17, 2003 |
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60530217 |
Dec 17, 2003 |
|
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60530397 |
Dec 17, 2003 |
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Current U.S.
Class: |
510/303 |
Current CPC
Class: |
A61K 8/8111 20130101;
A61K 8/22 20130101; A61Q 11/00 20130101 |
Class at
Publication: |
510/303 |
International
Class: |
D06L 001/00 |
Claims
What is claimed is:
1. A oral care delivery system comprising: a. an integral carrier;
and b. a safe and effective amount of a composition comprising: 1.
a safe and effective amount of a bleaching agent; 2. a safe and
effective amount of a water insoluble solid phase; and 3. a safe
and effective amount of a water soluble liquid phase; wherein the
ratio of the water insoluble solid phase to the water soluble
liquid phase is from about 1:4 to about 4:1; wherein the
composition is applied for a sufficient period of time to achieve
whitening; and wherein the delivery system is capable of adhesion
to hard or soft tissue of the oral cavity.
2. The delivery system of claim 1 wherein the composition has from
about 20% to about 80% by weight of the water soluble liquid
phase.
3. The delivery system of claim 2 wherein the ratio is from about
1:1.5 to about 1.5:1.
4. The delivery system of claim 3 wherein the ratio is from about
1:1.25 to about 1.25:1.
5. The delivery system of claim 2 wherein the composition comprises
from about 45% to about 65% by weight water soluble liquid
phase.
6. The composition of claim 5 wherein the composition comprises
from about 45% to about 60% by weight of the water insoluble solid
phase.
7. The delivery system of claim 2 wherein the water insoluble solid
phase is selected from the group consisting of polyolefins,
polyethylene, polypropylene, polyisoprenes, polyester, silicas,
talc, mica, magnesium carbonate, calcium carbonate, magnesium
silicate, aluminum magnesium silicate, titanium dioxide, zinc
oxide, nylon powder, methacrylate powder, polystyrene powder, silk
powder, crystalline cellulose, titanated mica, calcium phosphate,
calcium pyrophosphate, and mixtures thereof.
8. The delivery system of claim 7 wherein the water insoluble solid
phase is polyethylene.
9. The delivery system of claim 2 wherein the water insoluble solid
phase is selected from the group consisting of organic additives
and mixtures thereof.
10. The delivery system of claim 1 wherein the composition
comprises from about 0.1% to about 20% by weight bleaching agent
wherein the bleaching agent is selected from the group consisting
of peroxides, metal chlorites, perborates, percarbonates,
peroxyacids, persulfates, and combinations thereof.
11. The delivery system of claim 1 further comprising a Whitening
Index of from about 0.5 to about 4.
12. The delivery system of claim 11 wherein the Whitening Index is
from about 1.3 to about 3.5.
13. The delivery system of claim 1 wherein the integral carrier is
a strip of material.
14. The delivery system of claim 13 wherein the strip of material
and the composition applied thereon have an overall thickness of
less than about 1 mm.
15. The delivery system of claim 13 wherein the strip of material
has shallow pockets on a composition-coated side of the strip of
material, the shallow pockets having at least some of the
composition located therein.
16. The delivery system of claim 13 wherein the strip of material
is a polyethylene film having a film thickness of less than about
0.1 mm.
17. The delivery system of claim 13 wherein the composition is
applied as a substantially uniform continuous coating on the strip
of material.
18. The delivery system of claim 13 wherein the strip of material
is held in place by an adhesion means that is independent of the
composition.
19. The delivery system of claim 17 wherein the amount of
composition per square centimeter (cm) of material is less than
about 1 gram/cm.sup.2.
20. The delivery system of claim 1 wherein the integral carrier is
a tray.
21. The delivery system of claim 1 wherein the integral carrier is
a sponge material.
22. The delivery system of claim 1 wherein the composition further
comprises a dye, colorant, pigment, and mixtures thereof.
23. The delivery system of claim 1 wherein the composition further
comprises an associative thickener.
24. The delivery system of claim 23 wherein the associative
thickener is an acrylate/C10-C30 alkyl acrylate crosspolymer.
25. A method of increasing the efficacy of a bleaching agent in an
aqueous oral care composition comprising: 1. combining an oral care
delivery system comprising: a. an integral carrier; and b. a safe
and effective amount of a composition comprising: 1. a safe and
effective amount of a bleaching agent; 2. a safe and effective
amount of a water insoluble solid phase; and 3. a safe and
effective amount of a water soluble liquid phase; wherein the ratio
of the water insoluble solid phase to the water soluble liquid
phase from about 1:4 to about 4:1; and 2. thereafter applying a
safe and effective amount of the composition to a plurality of
teeth of a subject in need thereof for a sufficient period of time
to achieve whitening.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional
Application No. 60/530,387 filed Dec. 17, 2003, and U.S.
Provisional Application No. 60/530,217 filed Dec. 17, 2003, and
U.S. Provisional 60/530,397, filed Dec. 17, 2003.
TECHNICAL FIELD
[0002] The present invention relates to whitening compositions and
to a method of whitening teeth in a subject in need thereof. This
invention also relates to a method of increasing efficacy of a
bleaching agent in the oral cavity. The subject applies a
composition to a plurality of teeth for a sufficient period of time
to achieve whitening. The composition comprises a bleaching agent;
a water insoluble solid phase; and a water soluble liquid phase;
wherein the ratio of the water insoluble solid phase to the water
soluble liquid phase is from about 1:4 to about 4:1. In one
embodiment the composition has a Whitening Index of from about 0.5
to about 4.
[0003] In one embodiment the invention relates to a delivery system
comprising the present compositions and an integral carrier, e.g. a
strip of material, a dental tray, and/or a sponge material.
BACKGROUND OF THE INVENTION
[0004] Dental products by which various cosmetic and/or therapeutic
actives are delivered to teeth and the oral cavity are known.
Examples of such products include: brushing aids such as dentifrice
products for delivery of oral care actives such as polyphosphates
or fluorides; mouthwashes containing breath fresheners or
antibacterial actives; and whitening strips for the delivery of
bleaching actives to the teeth. In particular the use of a dental
strip has been recognized as a convenient and inexpensive way to
deliver cosmetic and therapeutic benefits to the teeth and mucosal
surfaces of the oral cavity. For example, dental whitening strips,
where a whitening composition is applied to a strip and thereafter
applied to the teeth to achieve sustained contact between the teeth
and the whitening composition, are known. See U.S. Pat. Nos.
6,136,297; 6,096,328; 5,894,017; 5,891,453; and 5,879,691, all to
Sagel, et al., and U.S. Pat. Nos. 5,989,569 and 6,045,811 both to
Dirksing, et al., all assigned to The Procter & Gamble
Company.
[0005] The prior art has generally attempted to increase whitening
efficacy by, among other things, increasing the level of the
bleaching agent in the compositions. This approach, however,
presents several problems. First the subject may experience
increased irritation and/or sensitivity which may be associated
with using an increased amount of a bleaching agent. Furthermore,
some regulatory authorities and legislation in various geographies
throughout the world do not allow bleaching agents to be used in
products at levels above certain concentrations.
[0006] Therefore, despite the above known approaches for the
treatment of oral conditions, especially for the whitening of
teeth, a need still exists for providing products with improved
bleaching efficacy. The present invention overcomes some of the
limitations of the prior art.
SUMMARY OF THE INVENTION
[0007] The present invention relates to a method of whitening teeth
of a subject in need thereof, by applying a safe and effective
amount of a composition to a plurality of teeth, the composition
comprising:
[0008] a. a safe and effective amount of a bleaching agent;
[0009] b. a safe and effective amount of a water insoluble solid
phase;
[0010] c. a safe and effective amount of a water soluble liquid
phase;
[0011] wherein the ratio of the water insoluble solid phase to the
water soluble liquid phase is from about 1:4 to about 4:1; wherein
the composition is applied for a sufficient period of time to
achieve whitening; and wherein the composition has a Whitening
Index of from about 0.5 to about 4. In another embodiment the
composition is single phase.
[0012] In one embodiment the present invention also relates to an
oral care composition comprising:
[0013] a. a safe and effective amount of a bleaching agent;
[0014] b. a safe and effective amount of a water insoluble solid
phase selected from the group consisting of organic additives and
mixtures thereof;
[0015] c. a safe and effective amount of a water soluble liquid
phase; and wherein the ratio of the water insoluble solid phase to
the water soluble liquid phase is from about 1:4 to about 4:1.
[0016] In another embodiment the present invention relates to an
oral care composition comprising:
[0017] a. a safe and effective amount of a bleaching agent;
[0018] b. a safe and effective amount of a water insoluble solid
phase;
[0019] c. a safe and effective amount of a water soluble liquid
phase; and
[0020] d. a safe and effective amount of associative thickener;
[0021] wherein the ratio of the water insoluble solid phase to the
water soluble liquid phase is from about 1:4 to about 4:1.
[0022] In another embodiment the present invention also relates to
an oral care delivery system comprising:
[0023] a. an integral carrier; and
[0024] b. a safe and effective amount of a composition
comprising:
[0025] 1. a safe and effective amount of a bleaching agent;
[0026] 2. a safe and effective amount of a water insoluble solid
phase; and
[0027] 3. a safe and effective amount of a water soluble liquid
phase;
[0028] wherein the ratio of the water insoluble solid phase to the
water soluble liquid phase is from about 1:4 to about 4:1; and
wherein the composition is applied for a sufficient period of time
to achieve whitening; and wherein the delivery system is capable of
adhesion to hard or soft tissue of the oral cavity.
[0029] In one embodiment the delivery system comprises: a first
layer of a strip material; a second layer comprising the above
composition, whereby the bleaching agent is releaseably associated
to the strip material. In one embodiment the present invention is
used to deliver whitening benefits to the oral cavity by directly
applying the integral carrier to the teeth.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] While the specification concludes with claims that
particularly point out and distinctly claim the present invention,
it is believed that the present invention will be understood better
from the following description of embodiments, taken in conjunction
with the accompanying drawings, in which like reference numerals
identify identical elements. The integral carrier includes a strip
of material, dental tray, sponge material, and mixtures thereof. In
one embodiment of the present invention, the integral carrier
comprises a strip of material. The strip of material is attached to
the teeth via an attachment means. The attachment means may be the
present composition, an adhesive composition separate from the
present composition, or via an attachment means that is part of the
integral carrier, e.g. the integral carrier may optionally be of
sufficient size and/or width and have sufficient adhesiveness,
that, once applied, the integral carrier overlaps with the oral
soft tissues rendering more of the teeth surface available for
bleaching.
[0031] Without intending to limit the invention, the strip of
material embodiment is described in more detail below:
[0032] FIG. 1 is a perspective view of a substantially flat strip
of material having rounded corners;
[0033] FIG. 2 is a perspective view of an embodiment of the present
invention, disclosing the strip of FIG. 1 upon which a second layer
composition comprising a composition described herein wherein the
bleaching agent is releaseably associated with the integral carrier
and/or the present composition;
[0034] FIG. 3 is a cross-sectional view, taken along section line
3-3 of FIG. 2, showing an example of the strip of material having a
thickness less than that of the second layer coated thereon;
[0035] FIG. 4 is a cross-sectional view, showing an alternative
embodiment of the present invention, showing shallow pockets in the
strip of material, which act as reservoirs for additional amounts
of the second layer coated on the strip;
[0036] FIG. 5 is a cross-sectional plan view, showing an
alternative embodiment for applying the second layer composition to
adjacent teeth having the strip of material of the present
invention conforming thereto and adhesively attached to the teeth
by means of the second layer composition located between the teeth
and the strip of material;
[0037] FIG. 6 is a cross-sectional elevation view of a tooth, taken
along section line 6-6 of FIG. 5, showing the strip of material of
the present invention conforming to and adhesively attached to the
teeth by means of the second layer composition located between the
teeth and strip of material;
[0038] FIG. 7 is a cross-sectional plan view, similar to FIG. 5,
showing a strip of material of the present invention conforming to
the teeth and the adjoining soft tissue and adhesively attached to
both sides of the teeth by means of the second layer composition
located between the teeth and the strip of material;
[0039] FIG. 8 is a cross-sectional elevation view, taken along
section line 8-8 of FIG. 7, showing a strip of material of the
present invention conforming to both the tooth and the adjoining
soft tissue and adhesively attached to both sides of the tooth by
means of the second layer composition located between the teeth and
the strip of material;
[0040] FIG. 9 is a perspective view of an alternative embodiment of
the present invention, disclosing the strip of material coated with
a second layer composition of FIG. 2 for treating teeth and
adjoining soft tissue having a release liner;
[0041] FIG. 10 is a cross-sectional view of an alternative
embodiment of the present invention, taken along section line 10-10
of FIG. 9, showing a release liner attached to the strip of
material by the second layer composition on the strip of the
material.
DETAILED DESCRIPTION
[0042] Definitions
[0043] By "oral care composition" or "oral composition" as used
herein is meant a product which is not intentionally swallowed for
purposes of systemic administration of therapeutic agents, but is
retained in the oral cavity for a sufficient time to contact the
dental surfaces for purposes of whitening efficacy.
[0044] By "safe and effective amount" as used herein is meant an
amount of a component, high enough to significantly (positively)
modify the condition to be treated or to effect the desired
whitening result, but low enough to avoid serious side effects (at
a reasonable benefit/risk ratio), within the scope of sound
medical/dental judgment. The safe and effective amount of a
component, will vary with the particular condition (e.g., to effect
whitening) being treated, the age and physical condition of the
patient being treated, the severity of the condition, the duration
of treatment, the nature of concurrent therapy, the specific form
employed, and the particular vehicle from which the component is
applied.
[0045] By "a sufficient period of time to achieve whitening" as
used herein means that the composition is used or worn by the
subject or the subject is instructed to use or wear the composition
for greater than about 2 minutes, in another embodiment from about
2.5 minutes to about 12 hours (e.g overnight treatment), in another
embodiment from about 3 minutes to about 120 minutes, in yet
another embodiment from about 5 minutes to about 40 minutes, per
application and may be applied from about 1 to about 7 times per
day. Additionally, the length of treatment to achieve the desired
benefit, for example, tooth whitening, may last from about one day
to about six months, in another embodiment from about one day to
about 28 days, and in another embodiment from about 7 to about 28
days. The optimal duration and frequency of application will depend
on the desired effect, the severity of any condition being treated,
the health and age of the user and like considerations.
[0046] By "cm" as used herein means centimeter. By "mm" as used
herein means millimeter.
[0047] All percentages and ratios used hereinafter are by weight of
total composition, unless otherwise indicated.
[0048] All measurements referred to herein are made at 25.degree.
C. unless otherwise specified.
[0049] All percentages, ratios, and levels of ingredients referred
to herein are based on the actual amount of the ingredient, and do
not include solvents, fillers, or other materials with which the
ingredient may be combined as a commercially available product,
unless otherwise indicated.
[0050] All publications, patent applications, and issued patents
mentioned herein are hereby incorporated in their entirety by
reference. Citation of any reference is not an admission regarding
any determination as to its availability as prior art to the
claimed invention.
[0051] Without being bound by theory, the present invention may
increase the "effective" concentration of the bleaching agent on
the surface of the teeth due to the replacement of some of the
aqueous phase with a water insoluble solid phase. In one embodiment
this may make the composition more hydrophobic. Therefore,
increased speed of whitening and/or increased efficacy of the
bleaching agent may be achieved, even though the same or lower
total level of the bleaching agent is used. The present invention,
therefore, at a given total concentration of bleaching agent, may
require fewer applications to get the same degree of whitening or
may require a lower gel load to get the same degree of
whitening.
Bleaching Agent
[0052] The compositions and methods in the methods of the present
invention comprise a safe and effective amount of a bleaching
agent. Generally the level of the bleaching agent is dependent on
the available oxygen or chlorine respectively that the molecule is
capable of providing to bleach the stain. The bleaching agent is
generally used in compositions of the present invention at levels
from about 0.1% to about 20%, in another embodiment from about 0.5
to about 9% and in another embodiment from about 3% to about 8%,
and in yet another embodiment from about 4% to about 6%, by weight
of the composition, of the bleaching agent. In one embodiment the
bleaching agent is surprisingly more effective when used at lower
levels generally from about 0.5% to about 3%, in another embodiment
from about 0.5% to about 1.5% by weight of the composition.
[0053] Bleaching agents are included in the compositions of the
present invention. In one embodiment bleaching agents are selected
from the group consisting of peroxides, metal chlorites,
perborates, percarbonates, peroxyacids, persulfates, compounds that
form the preceding compounds in situ, and combinations thereof.
Suitable peroxide compounds include hydrogen peroxide, urea
peroxide, calcium peroxide, carbamide peroxide, and mixtures
thereof. In one embodiment the bleaching agent is carbamide
peroxide. Suitable metal chlorites include calcium chlorite, barium
chlorite, magnesium chlorite, lithium chlorite, sodium chlorite,
potassium chlorite, and mixtures thereof. Additional bleaching
agents also include hypochlorite and chlorine dioxide. In one
embodiment the bleaching agent is selected from sodium chlorite,
peroxide, sodium percarbonate, oxones, and mixtures thereof. The
starting bleach agent can be aqueous or solid material.
Water Insoluble Solid Phase
[0054] The present invention comprises a safe and effective amount
of a water insoluble solid phase. Generally the water insoluble
solid phase comprises water insoluble organic and/or inorganic
(e.g. particulate) additives. The water insoluble solid phase is
generally water insoluble, non-toxic to the user and chemically
stable and compatible with the bleaching agent (e.g. not cause
substantial decomposition of the bleach agent) and the other
ingredients present in the composition. Generally, in one
embodiment, the present invention comprises from about 20% to about
80%, in another embodiment from about 30% to about 75% in another
embodiment from about 35% to about 65% and in another embodiment
from about 45% to about 60% by weight of the composition, of the
water insoluble solid phase.
[0055] Suitable materials for the water insoluble solid phase
include polyolefins (e.g., thermoplastic polymers, polymers derived
from simple olefins, polyethylene, polypropylene, polyisoprenes,
polybutene, and copolymers thereof) and polyester, and mixtures
thereof. For example polyethylene is available under the tradename
AC.RTM. and Accumist.RTM. available from Honeywell Allied Signal.
Additional materials for the water insoluble solid phase include
water insoluble celluloses (e.g. ethyl cellulose and cellulose
acetate), silicas, talc, mica, magnesium carbonate, calcium
carbonate, magnesium silicate, aluminum magnesium silicate,
titanium dioxide, zinc oxide, nylon powder, methacrylate powder,
polystyrene powder, silk powder, crystalline cellulose, titanated
mica, calcium phosphate, calcium pyrophosphate, and mixtures
thereof. In one embodiment the water insoluble solid phase is
selected from the group consisting of polyethylene, polypropylene,
polyisoprenes, copolymers thereof, and mixtures thereof.
[0056] In one embodiment the water insoluble solid phase comprises
less than about 5% by weight, in another embodiment less than about
2%, in another embodiment is essentially free of, dicalcium
phosphate dihydrate, anhydrous dicalcium phosphate, and/or calcium
pyrophosphate.
[0057] In one embodiment various dyes, colorants, pigments, and
mixtures thereof can either be optionally added to the present
composition or be optionally incorporated as part of the water
insoluble solid phase, to give the compositions herein colored
appearance. Any color, desired by the consumer, can be used,
including dyes or pigments that provide a color similar to the
color of natural teeth. One advantage of colored compositions is
that it allows the user to see if the composition covers their
teeth evenly and completely, since the degree of coverage on the
teeth is easier to see with a colored composition.
[0058] In one embodiment the water insoluble solid phase is a water
soluble material (e.g. water soluble starch material) that is
loaded into the composition at a high enough level to exceed its
solubility in the composition and thereafter function as the water
insoluble phase.
[0059] In one embodiment the average particle size of the water
insoluble solid phase, especially if an integral carrier (e.g.
strip) is used with the composition, is generally less than about
200 microns. In one embodiment, the average particle size of the
water insoluble solid phase is from about 5 to about 100, in
another embodiment from about 5 to about 80, in yet another
embodiment from about 10 to about 60, and in yet another embodiment
from about 10 to about 30 microns.
[0060] In one embodiment the water insoluble solid phase is
compatible with the bleaching agent, which means that the water
insoluble solid phase will not cause significant decomposition of
the bleach agent. In another embodiment "compatible with the
bleaching agent" means that a safe and effective amount of a
stabilizer is added to the water insoluble solid phase or to the
composition of this invention. In another embodiment the level of
optional stabilizer is from about 0.001% to about 15%, and in
another embodiment from about 0.01% to about 10%, in another
embodiment from about 0.5% to about 5%, in even another embodiment
from about 1% to about 3%, by weight of the composition.
[0061] In one embodiment, suitable optional stabilizers, such as
chelants or non-chelant stabilizers as known in the art, may be
selected from the group consisting of tartaric acid and
pharmaceutically acceptable salts thereof; citric acid and salts
thereof such as alkali metal citrates; pyrophosphate ion source;
polyphosphates (e.g., tripolyphosphate, hexametaphosphate);
diphosphonates (e.g., EHDP; AHP); EDTA; and mixtures thereof; and
in another embodiment may be selected from the group consisting of
sodium citrate, potassium citrate, disodium tartrate, dipotassium
tartrate, pyrophosphate ion source, sodium potassium tartrate,
disodium hydrogen tartrate, potassium hydrogen tartrate, disodium
dihydrogen pyrophosphate, tetrasodium pyrophosphate, tetrapotassium
pyrophosphate, and mixtures thereof.
Water Soluble Liquid Phase
[0062] The present invention comprises a safe and effective amount
of a water soluble liquid phase. Generally the level of the water
soluble liquid phase is from about 15% to about 80%, in another
embodiment from about 20% to about 75%, in another embodiment from
about 35% to about 70%, in another embodiment from about 45% to
about 65%, by weight of the composition. In another embodiment the
water soluble liquid phase is from about 15% to less than about
50%.
[0063] The water soluble liquid phase is generally selected from
the group consisting of water, polyalkylene glycols with molecular
weights from about 200 to about 20,000, humectants, and mixtures
thereof. The water soluble liquid phase can comprise water miscible
components such as polyalkylene glycols, humectants, and mixtures
thereof. Humectants generally include edible polyhydric alcohols
such as glycerin, sorbitol, xylitol, butylene glycol, polyethylene
glycol, and propylene glycol, and mixtures thereof. In one
embodiment the water soluble liquid phase is water. In one
embodiment the composition comprises at least about 10% water, in
another embodiment at least about 20% by weight of the composition,
of water.
Ratio of Water Insoluble Solid Phase to Water Soluble Liquid
Phase
[0064] The ratio of the water insoluble solid phase to the water
soluble liquid phase is from about 1:4 to about 4:1, in another
embodiment is from about 1:2.5 to about 2.5:1, in another
embodiment from about 1:1.5 to about 1.5:1, and in yet another
embodiment is from about 1:1.25 to about 1.25:1.
Whitening Index
[0065] In one embodiment, the present invention has a Whitening
Index of from about 0.5 to about 4, in another embodiment from
about 1 to about 4, in yet another embodiment from about 1.3 to
about 3.5, and in another embodiment from about 1.5 to about 3. The
Whitening Index is calculated as follows:
[0066] Db (for composition A) minus Db (for composition B) at
treatment day 1, 2, 3 or 4 wherein composition A and composition B
have the same concentration of bleaching agent, by weight of the
composition, and composition A is a composition of the present
invention, having the requisite amount of water insoluble solid
phase and water soluble liquid phase at a ratio of from about 1:4
to about 4:1, etc., and composition B does not.
[0067] Db for composition A is calculated as follows: 6-8 extracted
human molars are cleaned and are mounted into Lego.RTM. blocks, and
the front side of each molar is labeled to identify each molar. The
molars are re-hydrated overnight in either water or phosphate
buffer solution. Thereafter, the molars are removed from solution
and then 0.03 to 0.1 g of composition A is applied to the front
surface of each molar. The molars are then placed in a 37 degree C.
incubator during the duration of the treatment. Each molar is
treated with composition A for 30 minutes twice daily over a 4-day
study period. After 30 minutes treatment time, the molars are
removed from the incubator and are rinsed with distilled water to
remove any residual composition. The molars are placed in the water
or buffer solution in between each treatment. Two to four hours are
allowed between each treatment period.
[0068] Digital images of the molars are obtained pretreatment
(baseline) and after each total daily treatment (total daily
treatment is 1 hour). Digital images of the molars are captured on
computer using a high resolution digital camera (HC 1000 CCD.RTM.)
manufactured by Fuji, Japan. Theses images are analyzed to derive
numerical values for average tooth color in terms of standard
CIELAB.sup.1 three dimensional color space describing
lightness/brightness from blue to yellow (b). Treatment efficacy
after each day of treatment, b (calculated as the average b for
each molar tested) is compared to the baseline b (calculated as the
average b for each molar tested) for color measures b denoted as
Db. In one embodiment the baseline b value of the extracted human
molars ranges from about 10 to about 20, in another embodiment from
about 12 to about 16. .sup.1 Commission Internationale de l'
Eclairage L*a*b* capable of representing all possible colors using
three variables, a luninnce--L*; and color values on a red-green
axis--a*; and a blue-yellow axis--b*.
[0069] The Whitening Index can be calculated at day 1 or 2 or 3 or
4, or it can an average of the Db from days 1 to 4.
[0070] Db for composition B is calculated the same way as for
composition A except that composition B is used instead of
composition A.
Optional Thickening Agents
[0071] The compositions herein optionally comprise a thickening
agent. In one embodiment the thickening agent (or viscosity
modifier) functions to increase retention of the composition on the
teeth. The viscosity modifier may further function to inhibit
settling and separation of components or control settling in a
manner that facilitates re-dispersion and may control flow
properties of the composition. A viscosity modifier is particularly
useful to keep bleach agents or other oral care active agents, that
are in particulate form, suspended within the compositions of the
present invention. The thickening agent herein can also serve as
the adhesive means discussed herein below.
[0072] When present, the thickening agent (viscosity modifier) is
present at a level of from about 0.01% to about 20%, in one
embodiment from about 0.1% to about 10%, and in another embodiment
from about 0.4% to about 5%, and in yet another embodiment from
about 1% to about 3%, by weight of the composition.
[0073] Suitable viscosity modifiers herein include synthetic
polymers such as cellulose derivatives (e.g. methylcellulose,
carboxymethylcellulose, hydroxyethylcellulose,
hydroxypropylcellulose, hydroxy-propylmethylcellul- ose, etc.),
carbomer polymers (e.g. crosslinked polyacrylic acid copolymer or
homopolymer and copolymers of acrylic acid cross linked with a
polyalkenyl polyether), natural and synthetic gums, karaya gum,
guar gum, gelatin, algin, sodium alginate, tragacanth, chitosan,
polyethylene oxide, acrylamide polymers, polyacrylic acid,
polyvinyl alcohol, polyamines, polyquarternary compounds, ethylene
oxide polymers, polyvinylpyrrolidone, cationic polyacrylamide
polymers, and mixtures thereof.
[0074] In one embodiment the thickening agent is selected from
carbomers, e.g. the class of homopolymers of acrylic acid
crosslinked with an alkyl ether of pentaerythritol or an alkyl
ether of sucrose. Carbomers are commercially available from B.F.
Goodrich as the Carbopol.RTM. series. In one embodiment the
carbopols are Carbopol 934, 940, 941, 956, and mixtures thereof.
Homopolymers of polyacrylic acid are described, for example, in
U.S. Pat. No. 2,798,053. Other examples of homopolymers which are
useful include Ultrez 10, ETD 2050, and 974P polymers, which are
available from B.F. Goodrich Company. Such polymers are
homopolymers of unsaturated, polymerizable carboxylic monomers such
as acrylic acid, methacrylic acid, maleic acid, itaconic acid,
maleic anhydride, and the like.
[0075] In another embodiment the thickening agent can be an
associative thickener or stabilizer, such as a hydrophobically
modified alkali soluble acrylic emulsion or a hydrophobically
modified nonionic polyol polymer, i.e., a hydrophobically modified
urethane polymer, hydrophobically modified ethoxylated urethane
polymer or combinations thereof. Associative thickeners may
increase the retention or adhesion of compositions herein and/or
integral carriers on the tooth surfaces, may slow the erosion of
the compositions once applied on the tooth surfaces, and may
improve the release of the compositions from the optional release
liner disclosed herein.
[0076] Hydrophobically modified polyacrylic acid polymers are
described, for example, in U.S. Pat. Nos. 3,915,921, 4,421,902,
4,509,949, 4,923,940, 4,996,274, 5,004,598, and 5,349,030. These
polymers have a large water-loving hydrophilic portion (the
polyacrylic acid portion) and a smaller oil-loving hydrophobic
portion (which can be derived from a long carbon chain acrylate
ester). Representative higher alkyl acrylic esters are decycl
acrylate, lauryl acrylate, stearyl acrylate, behenyl acrylate and
melissyl acrylate, and the corresponding methacrylates. It should
be understood that more than one carboxylic monomer and more than
one acrylate ester or vinyl ester or ether or styrenic can be used
in the monomer charge. The polymers can be dispersed in water and
neutralized with base to thicken the aqueous composition, form a
gel, or emulsify or suspend a deliverable. Useful polymers are sold
as Carbopol.RTM. 1342 and 1382, and Carbopol.RTM. ETD 2020, and
Pemulen.RTM. TR-1, TR-2, 1621, and 1622, all available from BF
Goodrich. The carboxyl containing polymers are prepared from
monomers containing at least one activated vinyl group and a
carboxyl group, and would include copolymers of polymerizable
carboxylic monomers with acrylate esters, acrylamides, alkylated
acrylamides, olefins, vinyl esters, vinyl ethers, or styrenics. The
carboxyl containing polymers have molecular weights greater than
about 500 to as high as several billion, or more, usually greater
than about 10,000 to 900,000 or more.
[0077] Also useful are interpolymers of hydrophobically modified
monomers and steric stabilizing polymeric surface active agents
having at least one hydrophilic moiety and at least one hydrophobic
moiety or a linear block or random comb configuration or mixtures
thereof. Examples of steric stabilizers which can be used are
Hypermerl, which is a poly(12-hydroxystearic acid) polymer,
available from Imperial Chemical Industries Inc. and Pecosil.RTM.,
which is a methyl-3-polyethoxypropyl siloxane.OMEGA..-phosphate
polymer, available from Phoenix Chemical, Somerville, N.J. These
are taught by U.S. Pat. Nos. 4,203,877 and 5,349,030.
[0078] Other associative thickeners include Rohm and Haas (such as
Acrysol.RTM. ICS-1 and Aculyn.RTM. 22 and 28 thickeners, which are
hydrophobically modified alkali-soluble acrylic polymer emulsions
and Aculyn.RTM. 44 and 46 thickener, which is a hydrophobically
modified nonionic polyol). In one embodiment the associative
thickener is Carbopol.RTM. and/or Pemulen.RTM. polymers. The choice
of the specific polymer to be employed will depend upon the desired
rheology of the composition, and the identity of other
compositional ingredients.
[0079] Other associative thickeners are discussed in greater detail
in U.S. Pat. No. 5,997,764, BF Goodrich. In one embodiment mixtures
of hydrophobically modified carbomers with carbomers can be
used.
Combination of Integral Carrier and Composition
[0080] In one embodiment the present invention relates to a
delivery system comprising an integral carrier and the present
composition. In one embodiment the delivery system comprises: a
first layer of a strip of material; a second layer comprising the
above compositions, whereby the bleaching agent is releasably
associated with the composition and/or the strip of material. The
present invention delivers whitening benefits to the oral cavity by
directly applying the integral carrier to the teeth.
[0081] I. First Layer
[0082] The first layer of the present invention comprises an
integral carrier including a strip of material, dental tray, a
sponge material, and mixtures thereof. In one embodiment the
integral carrier is a strip of material.
[0083] Referring now to the drawings, and more particularly to
FIGS. 1 and 2, there is shown a first embodiment of the present
invention, generally indicated as 10, representing a delivery
system for delivering bleach actives to the teeth and the oral
cavity. Delivery system 10 has a strip of material 12, which is
substantially flat, preferably with rounded corners.
[0084] Releasably applied onto said strip of material 12 is a
second layer composition 14. Second layer composition 14 is, in one
embodiment, a homogenous, and may be uniformly and continuously
coated onto strip of material 12, as shown in FIG. 3. However,
second layer composition 14 may alternatively be a continuous
coating of second layer composition 14 along a longitudinal axis of
a portion of strip of material 12. In addition second layer
composition may be laminated or layered wherein the bleaching agent
and/or adhesive means may not be present in all layers or
laminates. In addition second layer composition may be an amorphous
mixture of compositions wherein the bleaching agent and/or adhesive
means may not be present in all phases of the amorphous mixture. In
addition second layer composition may be applied as stripes, spots,
and/or other patterns of the same or different compositions,
wherein the bleaching agent and/or adhesive means may not be
present in all stripes, spots, and/or other patterns of
compositions.
[0085] As shown in FIG. 4 in an alternative embodiment, strip of
material 12 may have shallow pockets 18 formed therein. When second
layer composition 14 is coated on a strip of material 12,
additional second layer composition 14, if present, fills shallow
pockets 18 to provide reservoirs of second layer composition
14.
[0086] FIGS. 5 and 6 show a delivery system 24 of the present
invention applied to the surface of a tooth and plurality of
adjacent teeth. Embedded in adjacent soft tissue 20 are a plurality
of adjacent teeth 22. Adjacent soft tissue herein defined as soft
tissue surfaces surrounding the tooth structure including: papilla,
marginal gingival, gingival sulculus, inter dental gingival, and
gingival gum structure on lingual and buccal surfaces up to and
including muco-gingival junction on the pallet.
[0087] In both FIGS. 5 and 6, delivery system 24 represents strip
of material 12 and second layer composition 14, with second layer
composition 14 on the side of strip material 12 facing tooth 22.
Second layer composition 14 may be pre-applied to strip of material
12, or may be applied to strip of material 12 by the user prior to
application to the teeth. In an alternate embodiment, the second
layer composition may be applied directly to teeth 22 by the user
and then covered by a strip of material 12. In any case, strip of
material 12 has a thickness and flexural stiffness such that it can
conform to the contoured surfaces of tooth 22 and to adjacent soft
tissue 20. In one embodiment, the strip of material has sufficient
flexibility to form to the contours of the oral surface, the
surface being a plurality of adjacent teeth. The strip of material
is also readily conformable to tooth surfaces and to the
interstitial tooth spaces without permanent deformation when the
delivery system is applied. The delivery system can be applied
without significant pressure.
[0088] FIGS. 7 and 8 show a delivery system 24 of the present
invention applied to both front and rear surfaces of a plurality of
adjacent teeth 22 as well as to adjacent soft tissue 20. Delivery
system 24 represents strip of material 12 and second layer
composition 14, with second layer composition 14 on the side of
strip of material 12 facing tooth 22.
[0089] FIGS. 9 and 10 shows an optional release liner 27. Release
liner 27 is attached to strip of material 12 by second layer
composition 14. Second layer composition 14 is on the side of strip
material 12 facing release liner 27. This side is applied to the
tooth and gum surfaces once release liner 27 is removed.
[0090] In one embodiment the first layer of the delivery system of
the present invention is comprised of a strip of material. Such
first layer materials are described in more detail in U.S. Pat.
Nos; 6,136,297; 6,096,328; 5,894,017; 5,891,453; and 5,879,691, all
to Sagel, et al., and all assigned to The Procter & Gamble
Company, and in U.S. Pat. Nos. 5,989,569 and 6,045,811 both to
Dirksing, et al., and both assigned to The Procter & Gamble
Company.
[0091] The strip serves as a protective barrier for the bleach. It
prevents leaching and/or erosion of the second layer by for
example, the wearer's tongue, lips, and saliva. This allows the
active in the second layer to act upon the hard surfaces of the
oral cavity for an extended period of time, from several minutes to
several hours.
[0092] The strip material may comprise polymers, natural and
synthetic woven materials, non-woven material, foil, paper, rubber
and combinations thereof. The strip material may be a single layer
of material or a laminate of more than one layer. Regardless of the
number of layers, the strip of material is, in one embodiment,
substantially water insoluble. The strip may also be water
impermeable. In one embodiment the material is any type of polymer
or combination of polymers that meet the required flexural rigidity
and are compatible with oral care substances. Suitable polymers
include, but are not limited to, polyethylene, ethylvinylacetate,
polyesters, ethylvinyl alcohol and combinations thereof. Examples
of polyesters include Mylar.RTM. and fluoroplastics such as
Teflon.RTM., both manufactured by Dupont. In one embodiment the
material is polyethylene. The strip of material is generally less
than about 1 mm (millimeter) thick, in one embodiment less than
about 0.05 mm thick, in yet another embodiment from about 0.001 to
about 0.03 mm thick. A polyethylene strip of material is generally
less than about 0.1 mm thick and in one embodiment from about 0.005
to about 0.02 mm thick.
[0093] The shape of the strip of material is any shape and size
that covers the desired oral surface. In one embodiment the strip
has rounded corners to avoid irritation of the soft tissue of the
oral cavity. "Rounded corners," means not having any sharp angles
or points. In one embodiment, the length of the strip material is
from about 2 cm (centimeter) to about 12 cm, in another embodiment
from about 4 cm to about 9 cm. The width of the strip material will
also depend on the oral surface area to be covered. The width of
the strip is generally from about 0.5 cm to about 4 cm, in one
embodiment from about 1 cm to about 2 cm. In yet another
embodiment, the strip may be worn as a patch on one or several
teeth to treat a localized condition.
[0094] The strip material may contain shallow pockets. When the
composition is coated on a strip of material, bleach agent and/or
oral care actives fill shallow pockets to provide reservoirs of
additional bleach agent and/or oral care actives. Additionally the
shallow pockets help to provide texture to the delivery system. In
one embodiment the strip material will have an array of shallow
pockets. Generally the shallow pockets are approximately 0.4 mm
across and about 0.1 mm deep. When shallow pockets are included in
the strip of material and the compositions herein are applied to it
in various thicknesses, the overall thickness of the delivery
system is less than about 1 mm. In one embodiment the overall
thickness is less than about 0.5 mm.
[0095] 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 terms of
deflection force. The rigidity of the sample is read directly from
the microammeter and expressed as grams per centimeter of the
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 Company of Philadelphia, Pa. as per test method ASTM
D2923-95. In one embodiment the strip has a flexural stiffness less
than about 3 grams/cm, in another embodiment less than about 2
grams/cm and in yet another embodiment from about 0.1 to about 1
grams/cm. Generally, the flexural stiffness of the strip of
material is substantially constant and does not 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.
[0096] This relatively low stiffness enables the strip of material
to cover the contours of the oral surface with very little force
being exerted. That is, conformity to the contours of the oral
surface of the wearer's mouth is maintained because there is little
residual force within the strip of material to cause it to return
to its shape just prior to its application to the oral surface,
i.e. substantially flat. The strip of material's flexibility
enables it to contact soft tissue over an extended period of time
without irritation. The strip of material does not require
continuous pressure for retention against the oral surface.
[0097] In one embodiment the delivery systems herein comprise an
adhesion means and are capable of adhesion to oral surfaces
especially the teeth. This adhesion means may be provided by the
present compositions herein or the adhesion means is provided
independently of the compositions herein (for example the adhesion
means is a separate phase from the compositons herein where the
compositions may or may not also have an adhesive means). In once
embodiment the strip of material is held in place on the oral
surface by adhesive attachment provided by the present
compositions. The viscosity and general tackiness of the present
compositions to dry surfaces cause the strip to be adhesively
attached to the oral surface without substantial slippage from the
frictional forces created by the lips, teeth, tongue, and other
oral surfaces rubbing against the strip of material while talking
drinking, etc. However, this adhesion to the oral surface is low
enough to allow the strip of material to be easily removed by the
wearer by simply peeling off the strip of material using one's
finger. The delivery system is easily removable from the oral
surfaces without the use of an instrument, a chemical solvent or
agent or excess friction.
[0098] In another embodiment the strip of material is held in place
on the oral surface by adhesive means and attachment provided by
the integral carrier itself. In one embodiment the strip of
material can extend, attach, and adhere to the oral soft tissue.
Alternatively, an adhesive can be applied to that portion of the
strip of material that will attach the delivery systems to the oral
soft tissue. In another embodiment the strip of material is held in
place by an adhesion means that is independent of the composition
of the present inventions herein, as disclosed in WO 03/015656,
published Feb. 27, 2003, SmithKline Beecham.
[0099] Examples of adhesion means being provided independent of the
compositions herein include the following.
[0100] In one embodiment, the composition and an adhesive material
may be deposited in separate discrete locations in relation to the
strip surface. In one embodiment the composition and adhesive may
be deposited on the surface of the strip in respective spatially
separated places on the surface. For example the adhesive may be
deposited in places on the strip surface that enable part of the
strip to stick to an oral surface adjacent to a tooth surface, e.g.
a gum surface, so that another part of the strip on which the
composition is deposited or into which it is impregnated may
contact the tooth surface.
[0101] Alternatively the adhesive and composition may be spatially
separated but both in locations that enable the adhesive and
composition to contact the same type of tissue, e.g. tooth or gum
surface, respective discrete spots or patches on the surface, that
are relatively small. For example parallel lines of the adhesive
and composition, one or more patches of composition bordered partly
or completely surrounded by a border of the adhesive, a single
large patch covering substantially the entire surface of the strip
and bordered partly or completely by a line of the adhesive.
Adhesive may be deposited on one or more patch bordered partly or
completely surrounded by a border of the composition.
[0102] In another embodiment the composition and/or adhesive may be
encapsulated. Encapsulation may for example be in micro-capsules,
or macro-capsules. Methods of micro-encapsulation are known, for
example in which a droplet of a substance in a liquid phase is
enclosed within a layer of an encapsulation material, and then
separated from the liquid. Such capsules may be deposited on or
adjacent the surface of the integral carrier, and may for example
be burst physically or chemically, e.g. by pressure e.g. as the
strip is applied to the tooth surface or by subsequent bit action,
by breaching of the capsule wall under the action of the
temperature, moisture, pH, chemicals or enzymes in the mouth
environment etc. For example respective capsules of composition and
adhesive may be attached to the surface of the strip, e.g. by means
of a second adhesive or by embedding the capsules in the strip of
material. For example a thin layer of the adhesive may be deposited
on the surface of the strip, and capsules of the composition may be
embedded at least partly if not completely within this adhesive
layer, or may sit upon the surface of this adhesive layer.
[0103] In another embodiment the adhesive may be provided in
granules, e.g. pellets or micropellets, which may release their
content under the influence of the mouth environment, for example
moisture, chemicals or enzymes in the mouth, and may be coated to
achieve this release. Methods of granulation and palletizing are
known, as are coating polymers such as the know Eudragit.TM.
polymers which dissolve at specified pH. Such adhesive granules may
be deposited on or adjacent the surface of the strip. For example
capsules and/or granules of adhesive may be located substantially
uniformly over the strip surface, or alternatively respective
capsules and/or granules of adhesive may be situated at separate
respective locations on the surface of the strip.
[0104] In another embodiment a layer of the composition may be
deposited relatively proximal to, e.g. adjacent to and in contact
with the surface, and a layer of the adhesive may be deposited
relatively distal from the surface e.g. adjacent to and in contact
with the underlying layer of composition. In such a construction
the adhesive may stick the strip to the tooth surface, and the
composition may pass through the adhesive layer, for example as the
adhesive layer becomes permeable under the influence of the mouth
environment. The adhesive layer may in such a construction have one
or more holes passing through the layer to facilitate the passage
of the composition through the adhesive layer. Alternatively for
example a layer of the adhesive may be deposited relatively
proximal to, e.g. adjacent to and in contact with the surface, and
a layer of the composition may be deposited relatively distal from
the surface e.g. adjacent to and in contact with an underlying
layer of adhesive. In such a construction the layer of composition
may need one or more holes passing through the layer to facilitate
the passage of the adhesive through the composition. In the above
constructions the passage of material from the underlying layer may
be facilitated by pressure as the strip is applied to the tooth
surface.
[0105] Mechanical adhesive means may also be used to provide an
adhesive function, used either alone or in combination with any
other adhesive device disclosed herein. In another embodiment
mechanical adhesion between the strip and tooth or other oral
surface is provided by the strip comprising a plastically
deformable material, which can be plastically deformed by the user
to conform the strip to the contours of the tooth or other oral
surface, and so adhere thereto by mechanical gripping. Such
gripping may be enhanced by e.g. surface effects between the strip
and the surface such as formation of a partial vacuum or surface
tension effects. For example the strip may have anchors on its
surface, positioned at approximately the spacings of gaps between
teeth, and these anchors may fit into the gaps between the teeth.
For example the surface of the strip which is to contact the tooth
surface may be provided with micro-suckers, that is a plurality of
small cavities in the surface of the strip which can be pressed
onto the tooth surface to drive air out therefrom, and thereby
create a partial vacuum, so that the strip is thereafter held on
the tooth surface by air pressure. Such anchors or micro-suckers
may be located on the surface of a strip which is to contact the
tooth surface. Such a strip may for example be stretchable, so that
it can be adjusted to the spacings of gaps between an individual
user's teeth. Another form of "mechanical" adhesion may be provided
by a strip which shrinks in contact with the tooth surface, so it
can physically grip the surface of the tooth.
[0106] When the adhesive means is provided by an adhesive, the
adhesive may be any adhesive which may be used to stick materials
to the tooth surface or to a surface of the oral cavity surfaces.
Suitable adhesives include skin, gum and muco adhesives, and should
be able to withstand the moisture, chemicals and enzymes of the
oral environment for long enough for the oral care actives and/or
bleach to take effect, but may be soluble and/or biodegradable
thereafter. Suitable adhesives may for example comprise water
soluble polymers, hydrophobic and/or non-water soluble polymers,
pressure and moisture sensitive adhesives, e.g. dry adhesives which
become tacky upon contact with the mouth environment, e.g. under
the influence of moisture, chemicals or enzymes etc. in the mouth.
Suitable adhesives include natural gums, synthetic resins, natural
or synthetic rubbers, those gums and polymers listed above under
"Thickening Agents", and various other tacky substances of the kind
used in known adhesive tapes, those known from U.S. Pat. No.
2,835,628.
[0107] Second Layer
[0108] In one embodiment the second layer comprises a safe and
effective amount of the present composition described herein.
[0109] Optional Release Liner
[0110] The release liner may be formed from any material which
exhibits less affinity for the second layer composition than the
second layer composition exhibits for itself and for the first
layer strip of material. The release liner may comprise a rigid
sheet of material such as polyethylene, paper, polyester, or other
material, which is then coated with a nonstick type material. 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 that 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 bandage design. A
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.
Combination of Soft/Rigid Dental Trays or Sponge Material (Foams)
and Composition
[0111] The delivery systems may be used in combination with a
dental tray. Dental trays are well known in the whitening art. The
general process for preparing dental trays is known in the art. For
example, an alginate impression which registers all teeth surfaces
plus gingival margin is made and a stone cast is promptly made of
the impression. If reservoirs are desired they are prepared by
building a layer of rigid material on the stone cast on specific
teeth surfaces to be treated. A dental tray is then vacuum formed
from the modified cast using conventional techniques. Once formed,
the tray is preferably trimmed barely shy of the gingival margin on
both buccal and lingual surfaces. Enough tray material should be
left to assure that all of the tooth will be covered to within
about 1/4 to about 1/3 mm of the gingival border upon finishing and
beveling the tray periphery. In one embodiment one can scallop up
and around interdental papilla so that the finished tray does not
cover them. All tray edges are preferably smoothed so that the lip
and tongue will not feel an edge prominence. The resulting tray, in
one embodiment, provides a perfect fit of the patient's teeth
optionally with reservoirs or spaces located where the rigid
material was placed on the stone cast. Dental trays may comprise of
soft transparent vinyl material having a preformed thickness from
about 0.04 inch to about 0.06 inch. Soft material is more
comfortable for the patient to wear. Harder material (or thicker
plastic) may also be used to construct the tray.
[0112] Dentists have traditionally utilized three types of dental
appliances for bleaching teeth. The first type is a rigid appliance
which is fitted precisely to the patient's dental arches. A second
type of rigid custom dental appliance is an "oversized" rigid
custom dental appliance. The fabrication of rigid, custom dental
appliances entails fabricating stone models of the patient's dental
arch impressions, and heating and vacuum-forming a thermoplastic
sheet to correspond to the stone models of a patient's dental
arches. Thermoplastic films are sold in rigid or semi rigid sheets,
and are available in various sizes and thickness. The dental
laboratory fabrication technique for the oversized rigid dental
appliance involves augmenting the facial surfaces of the teeth on
the stone models with materials such as die spacer or light cured
acrylics. Next, thermoplastic sheeting is heated and subsequently
vacuum formed around the augmented stone models of the dental arch.
The net effect of this method results in an "oversized" rigid
custom dental appliance.
[0113] A third type of rigid custom dental appliance, used with
less frequency, is a rigid bilaminated custom dental appliance
fabricated from laminations of materials, ranging from soft porous
foams to rigid, non-porous films. The non-porous, rigid
thermoplastic shells of these bilaminated dental appliances encase
and support an internal layer of soft porous foam.
[0114] A fourth type of dental tray replaces rigid custom dental
appliances with disposable U-shaped soft foam trays, which may be
individually packaged, and which may be saturated with a
pre-measured quantity of the composition of the present invention.
The soft foam material is generally an open celled plastic
material. Such a device is commercially available from Cadco Dental
Products in Oxnard, Calif. under the tradename VitalWhite.TM.. In
one embodiment these soft foam trays comprise a backing material
(e.g. a closed cell plastic backing material) to minimize the
elution of the bleaching agent from the device, into the oral
cavity to minimize ingestion by the patient and/or irritation of
the oral cavity tissues. In another embodiment the soft foam tray
is encased by a nonporous flexible polymer. In another embodiment
the open cell foam is attached to the frontal inner wall of the
dental appliance and/or the open cell foam is attached to the rear
inner wall of the dental appliance.
[0115] Those of ordinary skill in the art will readily recognize
and appreciate, that the present compositions must be thick enough
not to simply run out between the open cell structure of the foam
and must be thin enough to slowly pass through the open cell foam
over time. In other words, the open cell foam material has an
internal structural spacing sized relative to the viscosity of the
compositions to absorb and allow the composition to pass
therethrough.
[0116] An example of a closed cell material is a closed-celled
polyolefin foam sold by the Voltek division of Sekisui America
Corporation of Lawrence, Mass. under the tradename Volora which is
from {fraction (1/32)}" to 1/8" in thickness. A closed cell
material may also comprise of a flexible polymeric material.
[0117] An example of an opened cell material is an open celled
polyethylene foam sold by the Sentinel Foam Products division of
Packaging Industries Group, Inc. of Hyannis, Mass. under the
tradename Opcell which is from {fraction (1/16)}" to 3/8" in
thickness. Other open cell foam useful herein include hydrophilic
open foam materials such as hydrogel polymers (e.g Medicell.TM.
foam available from Hydromer, Inc. Branchburg, J.J.). Open cell
foam may also be hydrophilic open foam material imbibed with agents
to impart high absorption of fluids, such as polyurethane or
polyvinylpyrrolidone chemically imbibed with various agents.
[0118] Appliances of the above type are further described in U.S.
Pat. Nos. 5,980,249, M. G. Fontenot, and U.S. Pat. No. 5,575,654,
M. G. Fontenot.
[0119] The above dental appliances may be designed to be disposable
or reuseable. Further dental trays are disclosed in U.S. Pat. No.
6,368,576, Steven D. Jensen, issued Apr. 9, 2002; U.S. Pat. No.
6,309,625 Jensen, et al., issued Oct. 30, 2001; U.S. Pat. No.
6,183,251, Dan E. Fischer, issued Feb. 6, 2001; U.S. Pat. No.
6,036,943, Dan E. Fischer, issued Mar. 14, 2000; U.S. Pat. No.
5,985,249, Dan E. Fischer, issued Nov. 16, 1999; U.S. Pat. No.
5,846,058, Dan E. Fischer, issued Dec. 8, 1998; U.S. Pat. No.
6,382,979, Sherrill F. Lindquist, issued May 7, 2002; U.S. Pat. No.
5,098,303, Fischer, issued Mar. 24, 1992, and U.S. Pat. No.
5,855,870, Dan E. Fischer, issued Jan. 5, 1999.
Optional Oral Care Active Agents
[0120] The present invention may optionally comprise a safe and
effective amount of an oral care active agent selected from the
group consisting of anticalculus agent, fluoride ion source,
antimicrobial agents, dentinal desensitizing agents, anesthetic
agents, antifungal agents, anti-inflammatory agents, selective H-2
antagonists, anticaries agents, nutrients, and mixtures thereof.
The oral care active agent preferably contains an active at a level
where upon directed use, the benefit sought by the wearer is
promoted without detriment to the oral surface to which it is
applied. Examples of the oral conditions these actives address
include, but, are not limited to, appearance and structural changes
to teeth, whitening, stain bleaching, stain removal, plaque
removal, tartar removal, cavity prevention and treatment, inflamed
and/or bleeding gums, mucosal wounds, lesions, ulcers, aphthous
ulcers, cold sores, tooth abscesses, and the elimination of mouth
malodor resulting from the conditions above and other causes such
as microbial proliferation.
[0121] Suitable oral care actives include any material that is
generally considered safe for use in the oral cavity and that
provides changes to the overall appearance and/or health of the
oral cavity. The level of oral care substance in the compositions
of the present invention is generally, unless specifically noted,
from about 0.01% to about 50%, preferably from about 0.1% to about
20%, more preferably from about 0.5% to about 10%, and even more
preferably from about 1% to about 7%, by weight of the
composition.
[0122] Oral care compositions or substances of the present
invention may include many of the actives previously disclosed in
the art. The following is a non-limiting list of oral care actives
that may be used in the present invention.
[0123] Anticaries Agents and Fluoride Ion Source
[0124] The present composition may comprise a safe and effective
amount of an anticaries agent, and mixtures thereof. In one
embodiment the anticaries agent is selected from the group
consisting of xylitol, fluoride ion source, and mixtures thereof.
The fluoride ion source provides free fluoride ions during the use
of the composition. In one embodiment the oral care active agent is
a fluoride ion source selected from the group consisting of sodium
fluoride, stannous fluoride, indium fluoride, organic fluorides
such as amine fluorides, and sodium monofluorophosphate. Sodium
fluoride is the fluoride ion in another embodiment. Norris et al.,
U.S. Pat. No. 2,946,725, issued Jul. 26, 1960, and Widder et al.,
U.S. Pat. No. 3,678,154 issued Jul. 18, 1972, disclose such
fluoride salts as well as others that can be used as the fluoride
ion source. These patents are incorporated herein by reference in
their entirety.
[0125] Preferably the instant compositions provide from about 50
ppm to 10,000 ppm, more preferably from about 100 to 3000 ppm, of
fluoride ions in the compositions that contact dental surfaces when
used with the delivery system of the present invention.
[0126] Anticalculus Agents
[0127] The present compositions may comprise a safe and effective
amount of at least one anticalculus agent. This amount is generally
from about 0.01% to about 40% by weight of the composition, in
another embodiment is from about 0.1% to about 25%, and in yet
another embodiment is from about 4.5% to about 20%, and in yet
another embodiment is from about 5% to about 15%, by weight of the
composition. The anticalculus agent should also be essentially
compatible with the other components of the composition.
[0128] The anticalculus agent is selected from the group consisting
of polyphosphates and salts thereof; polyamino propane sulfonic
acid (AMPS) and salts thereof; polyolefin sulfonates and salts
thereof; polyvinyl phosphates and salts thereof; polyolefin
phosphates and salts thereof; diphosphonates and salts thereof;
phosphonoalkane carboxylic acid and salts thereof; polyphosphonates
and salts thereof; polyvinyl phosphonates and salts thereof;
polyolefin phosphonates and salts thereof; polypeptides; and
mixtures thereof. In one embodiment, the salts are alkali metal
salts. In another embodiment the anticalculus agent is selected
from the group consisting of polyphosphates and salts thereof;
diphosphonates and salts thereof; and mixtures thereof. In another
embodiment the anticalculus agent is selected from the group
consisting of pyrophosphate, polyphosphate, and mixtures
thereof.
[0129] Polyphosphate
[0130] In one embodiment of the present invention, the anticalculus
agent is a polyphosphate. A polyphosphate is generally understood
to consist of two or more phosphate molecules arranged primarily in
a linear configuration, although some cyclic derivatives may be
present. Linear polyphosphates correspond to (X PO.sub.3).sub.n
where n is about 2 to about 125, wherein preferably n is greater
than 4, and X is for example sodium, potassium, etc. For (X
PO.sub.3).sub.n when n is at least 3 the polyphosphates are glassy
in character. Counterions for these phosphates may be the alkali
metal, alkaline earth metal, ammonium, C.sub.2-C.sub.6
alkanolammonium and salt mixtures. Polyphosphates are generally
employed as their wholly or partially neutralized water soluble
alkali metal salts such as potassium, sodium, ammonium salts, and
mixtures thereof. The inorganic polyphosphate salts include alkali
metal (e.g. sodium) tripolyphosphate, tetrapolyphosphate, dialkyl
metal (e.g. disodium) diacid, trialkyl metal (e.g. trisodium)
monoacid, potassium hydrogen phosphate, sodium hydrogen phosphate,
and alkali metal (e.g. sodium) hexametaphosphate, and mixtures
thereof. Polyphosphates larger than tetrapolyphosphate usually
occur as amorphous glassy materials. In one embodiment the
polyphosphates are those manufactured by FMC Corporation which are
commercially known as Sodaphos (n.apprxeq.6), Hexaphos
(n.apprxeq.13), and Glass H (n.apprxeq.21), and mixtures thereof.
The present compositions will typically comprise from about 0.5% to
about 20%, in one embodiment from about 4% to about 15%, in yet
another embodiment from about 6% to about 12%, by weight of the
composition of polyphosphate.
[0131] The phosphate sources are described in more detail in Kirk
& Othmer, Encyclopedia of Chemical Technology, Fourth Edition,
Volume 18, Wiley-Interscience Publishers (1996), pages 685-707,
incorporated herein by reference in its entirety, including all
references incorporated into Kirk & Othmer.
[0132] In one embodiment the polyphosphates are the linear "glassy"
polyposphates having the formula:
XO(XPO.sub.3).sub.nX
[0133] wherein X is sodium or potassium; and n averages from about
6 to about 125.
[0134] In one embodiment, when n is at least 2 in either of the
above polyphosphate formulas, the level of anticalculus agent is
from about 4.5% to about 40%, in another embodiment is from about
5% to about 25%, and in even another embodiment is from about 8% to
about 15%, by weight of the composition. Polyphosphates are
disclosed in U.S. Pat. No. 4,913,895, herein incorporated by
reference.
[0135] Pyrophosphate
[0136] The pyrophosphate salts useful in the present compositions
include, alkali metal pyrophosphates, di-, tri-, and mono-potassium
or sodium pyrophosphates, dialkali metal pyrophosphate salts,
tetraalkali metal pyrophosphate salts, and mixtures thereof. In one
embodiment the pyrophosphate salt is selected from the group
consisting of trisodium pyrophosphate, disodium dihydrogen
pyrophosphate (Na.sub.2H.sub.2P.sub.2O- .sub.7), dipotassium
pyrophosphate, tetrasodium pyrophosphate (Na.sub.4P.sub.2O.sub.7),
tetrapotassium pyrophosphate (K.sub.4P.sub.2O.sub.7), and mixtures
thereof. The pyrophosphate salts described in U.S. Pat. No.
4,515,772, issued May 7, 1985, and U.S. Pat. No. 4,885,155, issued
Dec. 5, 1989, both to Parran et al., are incorporated herein by
reference in their entirety, as well as the references disclosed
therein. The pyrophosphate salts are described in more detail in
Kirk & Othmer, Encyclopedia of Chemical Technology, Third
Edition, Volume 17, Wiley-Interscience Publishers (1982), pages
685-707, incorporated herein by reference in its entirety,
including all references incorporated into Kirk & Othmer.
[0137] In one embodiment, the compositions of the present invention
comprise tetrasodium pyrophosphate. Tetrasodium pyrophosphate may
be the anhydrous salt form or the decahydrate form, or any other
species stable in solid form in the present compositions. The salt
is in its solid particle form, which may be its crystalline and/or
amorphous state, with the particle size of the salt preferably
being small enough to be aesthetically acceptable and readily
soluble during use.
[0138] The level of pyrophosphate salt in the compositions of the
present invention is any safe and effective amount, and is
generally from about 1.5% to about 15%, in another embodiment from
about 2% to about 10%, and yet in another embodiment from about 3%
to about 8%, by weight of the composition.
[0139] Other Anticalculus Agents
[0140] Polyolefin sulfonates include those wherein the olefin group
contains 2 or more carbon atoms, and salts thereof. Polyolefin
phosphonates include those wherein the olefin group contains 2 or
more carbon atoms. Polyvinylphosphonates include
polyvinylphosphonic acid. Diphosphonates and salts thereof include
azocycloalkane-2,2-diphosphonic acids and salts thereof, ions of
azocycloalkane-2,2-diphosphonic acids and salts thereof (such as
those which the alkane moiety has five, six or seven carbon atoms,
in which the nitrogen atom is unsubstituted or carries a lower
alkyl substitutent, e.g. methyl), azacyclohexane-2,2-diph- osphonic
acid, azacyclopentane-2,2-diphosphonic acid,
N-methyl-azacyclopentane-2,3-diphosphonic acid, EHDP
(ethanehydroxy-1,1,-diphosphonic acid), AHP
(azacycloheptane-2,2-diphosph- onic acid, a.k.a.
1-azocycloheptylidene-2,2-diphosphonic acid),
ethane-1-amino-1,1-diphosphonate, dichloromethane-diphosphonate,
etc. Phosphonoalkane carboxylic acid or their alkali metal salts
include PPTA (phosphonopropane tricarboxylic acid), PBTA
(phosphonobutane-1,2,4-tricar- boxylic acid), each as acid or
alkali metal salts. Polyolefin phosphates include those wherein the
olefin group contains 2 or more carbon atoms. Polypeptides include
polyaspartic and polyglutamic acids.
[0141] Azacycloalkane-2,2-diphosphonic acids are disclosed in U.S.
Pat. No. 3,941,772, issued Mar. 2, 1976, Ploger et al., assigned to
Henkel and U.S. Pat. No. 3,988,443, issued Oct. 26, 1976, Ploger et
al., which are herein incorporated by reference in their
entirety.
[0142] Optional agents to be used in place of or in combination
with the pyrophosphate salt include such known materials as
synthetic anionic polymers, including polyacrylates and copolymers
of maleic anhydride or acid and methyl vinyl ether (e.g., Gantrez),
as described, for example, in U.S. Pat. No. 4,627,977, to Gaffar et
al., the disclosure of which is incorporated herein by reference in
its entirety; as well as, e.g., polyamino propoane sulfonic acid
(AMPS), zinc citrate trihydrate, polyphosphates (e.g.,
tripolyphosphate; hexametaphosphate), diphosphonates (e.g., EHDP;
AHP), polypeptides (such as polyaspartic and polyglutamic acids),
and mixtures thereof.
[0143] Antimicrobial Agents
[0144] Antimicrobial antiplaque agents may also by optionally
present in the present compositions. Such agents may include, but
are not limited to, triclosan,
5-chloro-2-(2,4-dichlorophenoxy)-phenol, as described in The Merck
Index, 11th ed. (1989), pp. 1529 (entry no. 9573) in U.S. Pat. No.
3,506,720, and in European Patent Application No. 0,251,591 of
Beecham Group, PLC, published Jan. 7, 1988; chlorhexidine (Merck
Index, no. 2090), alexidine (Merck Index, no. 222; hexetidine
(Merck Index, no. 4624); sanguinarine (Merck Index, no. 8320);
benzalkonium chloride (Merck Index, no. 1066); salicylanilide
(Merck Index, no. 8299); domiphen bromide (Merck Index, no. 3411);
cetylpyridinium chloride (CPC) (Merck Index, no. 2024;
tetradecylpyridinium chloride (TPC); N-tetradecyl-4-ethylpyridinium
chloride (TDEPC); octenidine; delmopinol, octapinol, and other
piperidino derivatives; effective antimicrobial amounts of
essential oils and combinations thereof for example citral,
geranial, and combinations of menthol, eucalyptol, thymol and
methyl salicylate; antimicrobial metals and salts thereof for
example those providing zinc ions, stannous ions, copper ions,
and/or mixtures thereof; bisbiguanides, or phenolics; antibiotics
such as augmentin, amoxicillin, tetracycline, doxycycline,
minocycline, and metronidazole; and analogs and salts of the above
antimicrobial antiplaque agents; anti-fungals such as those for the
treatment of candida albicans. If present, these agents generally
are present in a safe and effective amount for example from about
0.1% to about 5% by weight of the compositions of the present
invention.
[0145] Antiinflammatory Agents
[0146] Anti-inflammatory agents may also be present in the oral
compositions of the present invention. Such agents may include, but
are not limited to, non-steroidal anti-inflammatory agents such as
aspirin, ketorolac, flurbiprofen, ibuprofen, naproxen,
indomethacin, aspirin, ketoprofen, piroxicam and meclofenamic acid,
COX-2 inhibitors such as valdecoxib, celecoxib and rofecoxib, and
mixtures thereof. If present, the anti-inflammatory agents
generally comprise from about 0.001% to about 5% by weight of the
compositions of the present invention. Ketorolac is described in
U.S. Pat. No. 5,626,838, issued May 6, 1997, incorporated herein by
reference in its entirety.
[0147] H-2 Antagonists
[0148] The present invention may also include a safe and effective
amount of a selective H-2 antagonist. Selective H-2 antagonists
include compounds which are disclosed in U.S. Pat. Nos. 5,294,433
and 5,364,616 Singer et al., issued Mar. 15, 1994 and Nov. 15, 1994
respectively and assigned to Procter & Gamble, wherein the
selective H-2 antagonist is selected from the group consisting of
cimetidine, etintidine, ranitidine, ICIA-5165, tiotidine,
ORF-17578, lupitidine, donetidine, famotidine, roxatidine,
pifatidine, lamtidine, BL-6548, BMY-25271, zaltidine, nizatidine,
mifentidine, BMY-25368 (SKF-94482), BL-6341A, ICI-162846,
ramixotidine, Wy-45727, SR-58042, BMY-25405, loxtidine, DA-4634,
bisfentidine, sufotidine, ebrotidine, HE-30-256, D-16637, FRG-8813,
FRG-8701, impromidine, L-643728, and HB-408. Particularly preferred
is cimetidine (SKF-92334),
N-cyano-N'-methyl-N"-(2-(((5-methyl-1H-imidazol-4-
-yl)methyl)thio)ethyl)guanidine: 1
[0149] Cimetidine is also disclosed in the Merck Index, 11th
edition (1989), p. 354 (entry no. 2279), and Physicians' Desk
Reference, 46th edition (1992), p. 2228. Related preferred H-2
antagonists include burimamide and metiamide.
[0150] Nutrients
[0151] Nutrients may improve the condition of the oral cavity and
can be included in the oral care compositions or substances of the
present invention. Nutrients include minerals, vitamins, oral
nutritional supplements, enteral nutritional supplements, and
mixtures thereof.
[0152] Minerals that can be included with the compositions of the
present invention include calcium, phosphorus, fluoride, zinc,
manganese, potassium and mixtures thereof. These minerals are
disclosed in Drug Facts and Comparisons (loose leaf drug
information service), Wolters Kluer Company, St. Louis, Mo.,
.COPYRGT.1997, pp 10-17.
[0153] Vitamins can be included with minerals or used separately.
Vitamins include Vitamins C and D, thiamine, riboflavin, calcium
pantothenate, niacin, folic acid, nicotinamide, pyridoxine,
cyanocobalamin, para-aminobenzoic acid, bioflavonoids, and mixtures
thereof. Such vitamins are disclosed in Drug Facts and Comparisons
(loose leaf drug information service), Wolters Kluer Company, St.
Louis, Mo., .COPYRGT.1997, pp. 3-10.
[0154] Oral nutritional supplements include amino acids,
lipotropics, fish oil, and mixtures thereof, as disclosed in Drug
Facts and Comparisons (loose leaf drug information service),
Wolters Kluer Company, St. Louis, Mo., .COPYRGT.1997, pp. 54-54e.
Amino acids include, but, are not limited to L-Tryptophan,
L-Lysine, Methionine, Threonine, Levocarnitine or L-carnitine and
mixtures thereof. Lipotropics include, but, are not limited to
choline, inositol, betaine, linoleic acid, linolenic acid, and
mixtures thereof. Fish oil contains large amounts of Omega-3 (N-3)
Polyunsaturated fatty acids, eicosapentaenoic acid and
docosahexaenoic acid.
[0155] Antioxidants that may be included in the oral care
composition or substance of the present invention include, but are
not limited to Vitamin E, ascorbic acid, Uric acid, carotenoids,
Vitamin A, flavonoids and polyphenols, herbal antioxidants,
melatonin, aminoindoles, lipoic acids and mixtures thereof.
[0156] Enteral nutritional supplements include, but, are not
limited to protein products, glucose polymers, corn oil, safflower
oil, medium chain triglycerides as disclosed in Drug Facts and
Comparisons (loose leaf drug information service), Wolters Kluer
Company, St. Louis, Mo., .COPYRGT.1997, pp. 55-57.
[0157] Desensitizing Agents
[0158] Anti-pain or desensitizing agents can also be present in the
oral care compositions or substances of the present invention. Such
agents may include, but are not limited to, strontium chloride,
potassium nitrate, natural herbs such as gall nut, Asarum, Cubebin,
Galanga, scutellaria, Liangmianzhen, Baizhi, etc.
[0159] Optional Colorants
[0160] Dyes, pigments, colorants, and mixtures thereof may
optionally be included in the compositions of the present invention
to give the compositions herein colored appearance. An advantage of
adding pigments and/or colorants to the compositions herein is that
it will allow the user to see if the composition covers their teeth
evenly and completely, since coverage is easier to see with a
colored composition. In one embodiment the colorant provides color
similar to the color of natural teeth. Colorants useful herein are
stable with the bleach agent and are those recognized as safe.
[0161] The levels of dye, pigments and colorants that are
optionally used herein are in the range of about 0.05% to about
20%, in another embodiment from about 0.10% to about 15% and in
another embodiment from about 0.25% to about 5% by weight of the
composition.
Methods of Manufacturing the Compositions
[0162] The integral carrier, such as a strip, may be formed by
several of the film making processes known in the art. In one
embodiment a strip of polyethylene is made by a blown process or a
cast process. Other processes including extrusion or processes that
do not affect the flexural rigidity of the strip of material are
also feasible. Additionally, the second layer composition may be
incorporated onto the strip during the processing of the strip. The
second layer composition may be a laminate on the strip.
Methods of Using the Compositions
[0163] The present invention can be applied to the teeth of a
consumer in the dental office by a dental professional, or can be
used at home by the consumer.
[0164] In practicing the present invention, the user applies the
composition or delivery system herein to one or more teeth. The
composition can be applied with a paint-on device, a syringe or
unit dose syringe, squeezable tube, a brush, a pen or brush tip
applicator, a doe's foot applicator, or the like, or even with the
finger(s). The composition can also be combined with an integral
carrier such as a strip of material, dental tray, and/or sponge
material, and thereafter applied to the teeth. In one embodiment,
the delivery systems herein are almost unnoticeable when applied to
the teeth.
[0165] Then, any residual composition may be easily removed by
wiping, brushing or rinsing the oral surface after a desired period
of time has elapsed, or in the normal course of tooth brushing or
other oral care activities.
[0166] It is not necessary to prepare the teeth before applying the
composition or delivery systems of the present invention. For
example, the user may or may not choose to brush the teeth or rinse
the mouth before applying the present invention. The surfaces of
the oral cavity are neither required to be dried nor to be
excessively wet with saliva or water before application. However,
it is believed that adhesion to the tooth enamel surfaces will be
improved if the teeth are dry prior to application.
[0167] Where the integral carrier is a strip of material, the
second layer composition may be coated on the strip of material, or
be applied by the user to the strip of material, or be applied by
the user to the teeth and then the strip of material placed over
the coated teeth. The amount of the second layer composition
applied to the strip of material or teeth may depend upon the size
and capacity of the strip of material, concentration of the bleach
agent and the desired benefit. Generally less than 1 gram of
composition is required, in one embodiment from about 0.001 grams
to about 0.0001 grams and in another embodiment from about 0.1 gram
to about 0.4 grams of composition is used. The amount of
composition per square centimeter (cm) of material is less than
about 1 gram/cm.sup.2, in another embodiment less than about 0.2
grams/cm.sup.2, in another embodiment about 0.0001 grams/cm.sup.2
to about 0.1 grams/cm.sup.2, and in yet another embodiment about
0.01 grams/cm.sup.2 to about 0.04 grams/cm.sup.2.
[0168] The composition of the present invention may be in the form
of a viscous liquid, paste, gel, solution or other suitable form.
In one embodiment the composition has a viscosity of from about 200
to about 1,000,000 cps at low shear rates (less than one
1/seconds). In another embodiment the viscosity is from about
100,000 to about 800,000 cps and in another embodiment from about
400,000 to about 600,000 cps.
[0169] In one embodiment the composition is a non-dentifrice,
non-foaming, whitening composition, e.g. a whitening gel, wherein
the whitening composition can for example, either be essentially
free of foaming surfactants and, or essentially free of a fluoride
ion source.
[0170] The present invention may allow for a decreased frequency of
application. For example, a 6% peroxide containing composition that
generally is used for 30 minutes twice daily for 2 weeks (e.g. for
a total application time of 14 hours), may show substantially
identical whitening efficacy by administering the same level of
peroxide but used in accordance with the present invention, wherein
the total application time is reduce to 6-10 hours. For example,
when used in accord with the present invention the same level of
bleach agent may achieve equal or similar efficacy with one 30
minute application per day for 14 days or a 30 minute application
twice daily for 7-10 days.
[0171] Dental tray appliances may be used as follows. The patient
or dental professional dispenses the present composition into a
soft or rigid dental appliance and then the subject places the
appliance over the subject's dental arch (or fits the device around
his or her teeth to keep the tray in position). Generally, the
recommended treatment period is the same as those discussed above.
At the end of the treatment period, the dental appliance is
removed, cleaned with water to remove any remaining composition,
and then stored until the next application.
[0172] The above-described compositions and delivery systems may be
combined in a kit which comprises: 1. composition and 2.
instructions for use; or comprises: 1. composition, 2. instructions
for use, and 3. an integral carrier.
[0173] The compositions of this invention are useful for both human
and other animals (e.g. pets, zoo, or domestic animals)
applications.
EXAMPLES
[0174] The following non-limiting examples further describe
preferred embodiments within the scope of the present invention.
Many variations of these examples are possible without departing
from the scope of the invention.
EXAMPLE I
[0175] The following compositions containing a bleaching agent, are
made by processing techniques described below:
1 Example 1 Example 2 Example 3 Ingredient Wt % Wt % Wt % Glycerin
10.0 10.0 10.0 Water 20.3 17.3 21.5 Carbopol 956.sup.2 2.0 5.0 0.8
Sodium Acid 0.4 0.4 0.4 Pyrophosphate Sodium Stannate 0.2 0.2 0.2
Sodium Saccharin 0.1 0.1 0.1 Polyethylene 50.0 50.0 50.0 Hydrogen
Peroxide (35% 17.0 17.0 17.0 active) Example 4 Example 5 Example 6
Ingredient Wt % Wt % Wt % Glycerin 10.0 10.0 10.0 Water 28.5 3.3
45.3 Carbopol ETD 2020.sup.3 2.3 Sodium Acid 0.4 0.4 0.4
Pyrophosphate Sodium Stannate 0.2 0.2 0.2 Sodium Saccharin 0.1 0.1
0.1 Polyethylene 50.0 50.0 25.0 Hydrogen Peroxide (35% 8.5 34.0
17.0 active) Carbopol 1342.sup.4 2.0 Carbopol 1382.sup.5 2.0
Example 7 Example 8 Ingredient Wt % Wt % Glycerin 10.0 10.0 Water
20.3 20.3 Pemulen TR 1.sup.6 2.0 Sodium Acid pyrophosphate 0.4 0.4
Sodium Stannate 0.2 0.2 Sodium Saccharin 0.1 0.1 Polypropylene 50.0
50.0 Hydrogen Peroxide (35% 17.0 17.0 active) Pemulen TR2.sup.7 2.0
.sup.2Available from BF Goodrich. .sup.3Available from BF Goodrich.
.sup.4Available from BF Goodrich. .sup.5Available from BF Goodrich.
.sup.6Available from BF Goodrich. .sup.7Available from BF
Goodrich.
[0176] Examples 1-8 are made via the following process. Carbopol or
Pemulen, glycerin, water, pyrophosphate, saccharin, stannate and
hydrogen peroxide are mixed together at room temperature for 15-20
minutes @ 150 rpms. The pH of the resulting mixture is then
adjusted to about 4.5-5.0 by adding a 50/50 sodium hydroxide
solution. Half of the desired amount of polyethylene is then mixed
with the above mixture for about 10 minutes at room temperature @
150 rpms. The remaining half of the polyethylene is then added and
mixed for another 10 minutes at room temperature @ 150 rpms to
provide the final gel formulation.
[0177] About 0.1-0.2 g of the above composition may be applied
directly to the teeth by any application methods disclosed herein.
Alternatively the above compositions may be combined with an
integral carrier such as a strip of material or tray and then
applied to the teeth. About 0.1-0.2 g or about 1-3 g of the above
composition may be combined with a strip of material or tray,
respectively. One example of a strip of material is a 0.013 mm
thick piece of polyethylene film. The strip of material may be
provided with 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/centimeter 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.
[0178] Any of the compositions described above can be used with any
of the integral carriers described herein, e.g. strip of material,
trays, and/or foam materials. In any of the above examples the
polyethylene can be white or the color of natural teeth, allowing
the user to apply a more even and continuous coating on the teeth.
The above examples have a Whitening Index of from about 0.5 to
about 4.
[0179] All documents cited in the Detailed Description of the
Invention are, in relevant part, incorporated herein by reference;
the citation of any document is not to be construed as an admission
that it is prior art with respect to the present invention.
[0180] While particular embodiments of the present invention have
been illustrated and described, it would be obvious to those
skilled in the art that various other changes and modifications can
be made without departing from the spirit and scope of the
invention. It is therefore intended to cover in the appended claims
all such changes and modifications that are within the scope of
this invention.
* * * * *