U.S. patent application number 10/754065 was filed with the patent office on 2005-02-17 for tooth whitening dental tray and method of use.
Invention is credited to Chopra, Suman K., Collins, Michael, Prencipe, Michael.
Application Number | 20050036957 10/754065 |
Document ID | / |
Family ID | 34316873 |
Filed Date | 2005-02-17 |
United States Patent
Application |
20050036957 |
Kind Code |
A1 |
Prencipe, Michael ; et
al. |
February 17, 2005 |
Tooth whitening dental tray and method of use
Abstract
A dental tray with a hydrophobic tooth whitening formulation
where the tooth whitening formulation is substantially non-water
soluble, and a method of using this dental tray to whiten the
teeth. The tooth whitening formulation is primarily comprised of a
hydrophobic polymer and a peroxide or a peroxide yielding compound.
Preferably the hydrophobic polymer is the condensation product of a
silicone resin and an organosiloxane. The dental tray is formed to
encompass the front and the rear surfaces of the teeth. The dental
tray is comprised of a thermoplastic or thermoset polymer. The
teeth whitening formulation is placed into the dental tray and the
tray placed against the teeth to be whitened. This is for a
sufficient period of time to at least partially whiten teeth. This
can be a period of time from about 0.5 hour to 2 hours or more. The
substantially non-aqueous tooth whitening formulation is effective
over a longer period of time since it is not significantly diluted
or removed from the dental tray during the treatment time.
Inventors: |
Prencipe, Michael; (West
Windsor, NJ) ; Chopra, Suman K.; (Dayton, NJ)
; Collins, Michael; (Hazlet, NJ) |
Correspondence
Address: |
Colgate-Palmolive Company
909 River Road
P.O. Box 1343
Piscataway
NJ
08855-1343
US
|
Family ID: |
34316873 |
Appl. No.: |
10/754065 |
Filed: |
January 7, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10754065 |
Jan 7, 2004 |
|
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10642458 |
Aug 15, 2003 |
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Current U.S.
Class: |
424/53 ;
433/217.1 |
Current CPC
Class: |
A61K 8/8176 20130101;
A61K 8/22 20130101; A61K 8/18 20130101; A61K 8/891 20130101; A61Q
11/00 20130101; A61C 19/066 20130101 |
Class at
Publication: |
424/053 ;
433/217.1 |
International
Class: |
A61K 007/20 |
Claims
1. A method of whitening teeth comprising forming a dental tray to
conform to teeth to be whitened, placing in said dental tray a
substantially non-water soluble whitening formulation having a
viscosity if about 50,000 cps to about 900,000 cps, applying said
dental tray to the teeth to be whitened for a period of time.
2. A method as in claim 1 wherein said substantially non-water
soluble whitening formulation has a viscosity of about 200,000 cps
to about 600,000 cps.
3. A method as in claim 1 wherein said substantially non-water
soluble whitening formulation has substantially the following
formula:
5 Component Content Hydrophobic Polymer 1 to 80 wt % Adhesive
Enhancing Agent 0 to 20 wt % Peroxide Whitening Agent 0.5 to 50 wt
% Surfactant 0 to 50 wt % Flavor 0.1 to 1 wt % Other Agents 0 to 10
wt %
4. A method as in claim 3 wherein said non-aqueous hydrophobic
polymer has a concentration of about 15 to about 40 weight %.
5. A method as in claim 3 wherein said adhesive enhancing agent has
a concentration of about 2 to about 15 weight %.
6. A method as in claim 3 wherein said peroxide whitening agent has
a concentration of about 10 to about 40 weight %.
7. A method as in claim 3 wherein said surfactant has a
concentration of about 15 to about 35 weight %.
8. A method as in claim 1 wherein said tray is comprised of one of
a thermoplastic resin and a thermoset resin.
9. A method as in claim 8 wherein said thermoplastic resin is
selected from the group consisting of polyethylene and
polypropylene polymers, derivatives and copolymers, polyurethanes
and derivatives, polycaprolactams, polystyrene and derivatives,
polybutadiene and derivatives, polyisoprene and derivatives, and
polymethacrylate and its derivatives
10. A method as in claim 1 wherein subsequent to a removal of said
tray from the teeth said teeth are treated with a desensitizing
formulation.
11. A method as in claim 10 wherein said desensiticizing contains
at least one of potassium nitrate, citric acid, citric acid salts
and strontium chloride.
12. A method as in claim 3 wherein said hydrophobic polymer is the
condensation product of a silicone resin and an organosiloxane.
13. A method as in claim 12 wherein said hydrophobic polymer is a
condensation product comprised of about 50 to 70 parts silicone
resin to 30 to 50 parts organosiloxane polymer.
14. A method as in claim 3 wherein said adhesive enhancing agent is
selected from the group consisting of waxes, nonionic polymers of
ethylene oxide and nonionic copolymers of ethylene oxide and
propylene oxide.
15. A dental tray for treating teeth with a whitening formulation
comprising a dental tray formed to substantially cover the front
and a rear surface of at least one tooth, said dental tray
containing a substantially non-water soluble whitening formulation
having a viscosity of about 50,000 cps to about 900,000 cps.
16. A dental tray as in claim 12 wherein said substantially
non-water soluble whitening formulation has a viscosity of about
200,000 cps to about 600,000 cps.
17. A dental tray as in claim 12 wherein said substantially
non-water soluble whitening formulation has substantially the
following formula:
6 Component Content Hydrophilic Polymer 1 to 80 wt % Adhesive
Enhancing Agent 0 to 20 wt % Peroxide Whitening Agent 0.5 to 50 wt
% Surfactant 0 to 50 wt % Flavor 0.1 to 1 wt % Other Agents 0 to 10
wt %
18. A dental tray as in claim 14 wherein said non-aqueous
hydrophilic polymer has a concentration of about 15 to about 40
weight %.
19. A dental tray as in claim 14 wherein said adhesive enhancing
agent has a concentration of about 2 to 15 weight %.
20. A dental tray as in claim 14 wherein said peroxide whitening
agent has a concentration of about 10 to 40 weight %.
21. A dental tray as in claim 12 wherein said peroxide whitening
agent has a concentration of about 15 to about 35 weight %.
22. A dental tray as in claim 19 wherein subsequent to a removal of
said tray from the teeth a tooth densiticizing composition is
placed into said tray.
23. A dental tray as in claim 15 wherein said non-aqueous
hydrophobic polymer is the condensation product of a silicone resin
and an organosiloxane.
24. A dental tray as in claim 23 wherein hydrophobic polymer is a
condensation product comprised of about 50 to 70 parts silicone
resin to 30 to 50 parts organosiloxane polymer.
25. A dental tray as in claim 15 wherein said adhesive enhancing
agent is selected from them group consisting of waxes, nonionic
polymers of ethylene oxide and nonionic copolymers of ethylene
oxide and propylene oxide
Description
[0001] This invention relates to a dental tray and formulation for
tooth whitening. More particularly this invention relates to a
substantially non-water soluble tooth whitening formulation in a
dental try and its use for tooth whitening.
BACKGROUND OF THE INVENTION
[0002] There is a general desire for people to have white teeth.
Such white teeth are an indication of a good health and in
particular good oral care health. A problem is that various foods
and the use of tobacco will discolor teeth. Beverages such as
coffee, tea and cola beverages can discolor teeth.
[0003] As a result various products and procedures have been
developed to whiten teeth. These products and procedures are either
purchased and/or used directly by the consumer or are applied by a
dentist or other professional. The more effective products and
procedures are those that are performed by a dental
professional.
[0004] Typically this consists of the dental professional forming a
dental tray from an impression of a persons teeth. The dental tray
is formed by any by any of the well known and well used procedures.
After the dental tray is formed to the structure of the teeth a
whitening formulation is placed in the tray and the tray placed
into the mouth and against the teeth to be treated. The tray with
the whitening composition in home use typically is left in the
mouth for from about 10 minutes to several hours; ie. up to 12 or
more hours. If the treatment is only in the dental office the time
of the treatment typically will be from about 0.5 hour to about 2
hours.
[0005] The products used solely by consumers primarily comprise
whitening strips and brush-on products. Whitening strips are
plastic strips with the whitening formulation on one surface. The
surface with the whitening formulation is pressed against ones
teeth and left in contact with the teeth for about 30 minutes. The
plastic strip then is removed. The brush-on products are painted
into teeth and the user keeping his/her mouth at least partially
open for up to about a minute until the formulation dries onto the
teeth. In both cases saliva will dilute and flush the tooth
whitening composition from the user's teeth. This is more so with
strips since foreign materials, such as a plastic strip, will
enhance saliva flow in the mouth. These are useful products to
remove some tooth staining. However, they are not as effective as
the use of dental trays, and in particular the use of dental trays
by dental professionals.
[0006] A problem with the various whitening compositions that are
used in dental trays is that they are substantially soluble in
water and saliva. This results in a dilution of the whitening
formulation during use. In order to overcome this problem producers
of these whitening formulations have increased the concentration of
the whitening actives. However, this causes a problem of increased
tooth sensitivity, gum irritation and the potential long term for
lesions. Another solution disclosed in U.S. Pat. No. 5,846,058 has
been to use higher viscosity tooth whitening compositions. This
increases dilution time and flush time but is not a full solution
to the problem. A better solution to this problem is to use a
carrier and actives that are substantially insoluble in water and
saliva, the carrier being about fully insoluble in water and
saliva. The active must have some solubility in order to attack and
remove tooth stains. However this should be at a low level. In this
way tooth whitening compositions with a lower concentration of
active can be used to enhance whitening through a longer contact
time at a more sustained active concentration.
BRIEF DESCRIPTION OF THE INVENTION
[0007] The dental tray can be formed from essentially any
thermoplastic or thermoset polymer. The only requirement is that
preferably it should be at least partially flexible to better fit
into the mouth and against the teeth to be treated with the tooth
whitening composition. The tooth whitening composition to be placed
into the dental tray will be a substantially non-water and
non-saliva soluble composition. The major components of this tooth
whitening composition will comprise a non-aqueous hydrophobic
polymer and a peroxide whitening agent; and optionally components
such as an adhesive enhancing agent, surfactant, flavor and
peroxide activator. Other optional materials such as substances
with antiseptic and medicinal properties also can be a part of the
tooth whitening composition. This tooth whitening composition will
have a viscosity of about 50,000 cps to about 900,000 cps, and
preferably about 200,000 cps to about 600,000 cps.
[0008] This tooth whitening composition is placed in the dental
tray and the dental tray applied to the teeth to be treated. The
tray is left in place for about 0.25 hour to about 4 hours and
preferably from about 0.5 hour to about 2 hours. After removal the
person may rinse his/her mouth.
[0009] After the treatment with the tooth whitening composition the
teeth can be treated with a tooth desensitizing formulation. This
can be via use of the tray for more severe conditions to the use of
a desensitizing toothpaste for several days. Such formulations will
contain potassium nitrate, citric acid, citric acid salts,
strontium chloride and the like. A process of a first step tooth
whitening procedure followed by a tooth desensitizing procedure is
preferred for persons who are susceptible to tooth sensitivity
problems.
DETAILED DESCRIPTION OF THE INVENTION
[0010] The present invention will be described in more detail with
reference to the preferred embodiments. However, modifications can
be made to these preferred embodiments and be within the disclosed
concept.
[0011] The dental tray can be of any conventional form and formed
from conventionally used thermoplastic polymers. Thermoset polymers
also can be used. Consequently the tray can range from highly
flexible to a low flexibility. The thermoplastic polymers are
highly preferred and those that can be used include polyethylene
and polypropylene polymers their derivatives and copolymers,
silicone elastomers, polyurethanes and derivatives,
polycaprolactams, polystyrene and derivatives, polybutadiene and
derivatives, polyisoprene and derivatives, and polymethacrylate and
its derivatives. These can be in a sheet, foam or a laminate form.
In forming the trays a cast is taken of the teeth and gum area of a
patient and set. A thermoplastic polymer film is placed over the
cast and vacuum formed to the shape of the teeth and gum margin of
the patient. This is now in the shape of a tray that can contain a
whitening formulation and be used to treat the patients teeth.
[0012] The term "hydrophobic" polymer or "water-insoluble" polymers
as employed herein refers to an organic polymer which is
substantially non-aqueous having a water solubility of less than
one gram per 100 grams of water at 25 C. Any such polymers that are
compatible with peroxide compounds or peroxide yielding compounds
and which can produce a tooth whitening composition having a
viscosity of about 1000 cps to about 900,000 cps, and preferably
about 10,000 cps to about 100,000 cps can be used.
[0013] The composition of the present invention is a viscous
suspension which maintains its consistency during storage enabling
the product to be painted on the tooth surface through the use of a
dental tray. The composition is comprised of a hydrophobic polymer
that is the primary carrier for the active whitening component
which preferably is a peroxide containing or peroxide yielding
compound. A preferred class of hydrophobic polymers are silicone
based polymers. There are other components such as adhesion
enhancing agents, flavors, sweetening agents, surfactants,
anti-microbial agents, anti-inflammatory agents, plaque buffers,
vitamins, anti-caries agents, anti-plaque agents, desenticizing
agents, coloring agents, pigments and opacifying agents.
1 Component Content Hydrophobic Polymer 1 to 80 wt % Adhesive
Enhancing Agent 0 to 20 wt % Peroxide Whitening Agent 0.5 to 50 wt
% Surfactant 0 to 50 wt % Flavor 0.1 to 1 wt % Other Components
(can be HOH) 0 to 10 wt %
[0014] The tooth whitening composition will have the following
general formula:
[0015] In accordance with the practice of the present invention the
hydrophobic polymer compositions in which a peroxide can be
dispersed are known in the art and many are commercially available.
The preferred silicone based hydrophobic polymers are produced by
condensing a silicone resin and an organosiloxane such as a
polydiorganosilioxane. The hydrophobic polymers are an elastomeric,
tacky material, adhesion of which to dental enamel surfaces can be
varied by altering the ratio of silicone resin to
polydiorganosiloxane in the copolymer molecule. For example
hydrophobic polymers available from the Dow-Corning Company under
the brand name BIO-PSA are pressure sensitive hydrophobic polymers
specifically designed for pharmaceutical use and are permeable to
many drug compounds and find application for the transdermal
application of various compounds. The BIO-PSA silicone polymers are
the copolymer product of mixing a silanol terminated
polydiorganosiloxane such as polydimethyl siloxane with a
silanol-containing silicone resin whereby the silanol groups of the
polydiorganosiloxane undergo a condensation reaction with the
silanol groups of the silicone resin so that the
polydiorganosiloxane is lightly crosslinked by the silicone resin
(that is, the polydiorganosiloxane chains are bonded together
through the resin molecules to give chain branching and
entanglement and/or a small amount of network character) to form
the silicone hydrophobic polymers. A catalyst, for example an
alkaline material such as ammonia, ammonium hydroxide or ammonium
carbonate can be mixed with the silanol-terminated
polydiorganosiloxane and the silicone resin to promote this
crosslinking reaction.
[0016] By copolymerizing the silicone resin with the silanol
terminated polydiorganosiloxane, there results a polymer with self
adhering properties and the cohesive properties of a soft elastomer
matrix characteristic of pressure sensitive polymers being
distinguished from the hard, non-elastomeric properties of other
silicone resins.
[0017] Modifying the silicone resin to polydiorganosiloxane ratio
will modify the tackiness of the hydrophilic polymer. This ratio
can be in the range of about 70:30 to about 50:50. For example, the
BIO PSA silicone sold by Dow-Corning is available in three silicone
resin to silicone polymer ratios namely, 65/35 (low tack), 60/40
(medium tack), 55/45 (high tack). This is available dissolved in
either ethyl acetate solvent or dimethicone.
[0018] The silicone based hydrophobic polymer is present in the
liquid whitening compositions of the present invention at a
concentration of about 1 to about 80% by weight and preferably
about 15 to about 40% by weight.
[0019] Organic materials which may be included in the compositions
of the present invention to enhance the properties of the
hydrophobic polymers of the present invention include adhesion
enhancing agents such as waxes inclusive of bees wax, mineral oil,
plastigel, (a blend of mineral oil and polyethylene), petrolatum,
white petrolatum, shellac, versagel (blend of liquid paraffin,
butene/ethylene/styrene hydrogenated copolymer) polyethylene waxes,
microcrystalline waxes, polyisobutene, polyvinyl pyrrolidone/vinyl
acetate copolymers, and insoluble polyacrylate copolymers. Also
effective as adhesion enhancing agents are liquid hydrophilic
polymers including polyethylene glycols, nonionic polymers of
ethylene oxide having the general formula:
HOCH.sub.2(CH.sub.2OCH.sub.2).sub.nCH.sub.2OH
[0020] wherein n represents the average number of oxyethylene
groups. Polyethylene glycols available from Dow Chemical are
designated by a number such as 200, 300, 400, 600, 2000 which
represents the approximate average molecular weight of the polymer,
as well as nonionic block copolymer of ethylene oxide and propylene
oxide of the formula:
HO(CH.sub.4O).sub.a(C.sub.3H.sub.6O).sub.b(C.sub.2H.sub.4O).sub.cH
[0021] The block copolymer is preferably chosen (with respect to a,
b and c) such that the ethylene oxide constituent comprises from
about 65 to about 75% by weight, of said copolymer molecule and the
copolymer has an average molecular weight of from about 2,000 to
about 15,000 with the copolymer being present in the liquid tooth
whitening composition in such concentration that the composition is
liquid at room temperatures (23.degree. C.).
[0022] A particularly desirable block copolymer for use in the
practice of the present invention is available commercially from
BASF and designated Pluraflo L1220 which has an average molecular
weight of about 9,800. The hydrophilic poly(ethylene oxide) block
averages about 65% by weight of the polymer.
[0023] Typically, adhesion enhancing polymers employed in the
compositions of the invention are present in an amount of from
about 0 to 20% by weight. Preferably, the polymers are present in
an amount of from about 2 to about 15% by weight.
[0024] Peroxide releasing compounds useful in the practice of the
present invention include peroxide containing compounds such as
urea peroxide, sodium percarbonate, sodium perborate and
PVP-H.sub.20.sub.2 complexes (hereinafter "PVP-H.sub.20.sub.2").
PVP-H.sub.20.sub.2 both linear and cross linked complexes are known
to the art and are disclosed in U.S. Pat. No. 3,376,110 and U.S.
Pat. No. 3,480,557 and have been used in compositions for treating
acne vulgaris (U.S. Pat. No. 5,122,370). PVP-H.sub.20.sub.2
complexes are disclosed in U.S. Pat. No 5,122,370.
PVP-H.sub.20.sub.2 is stable in an anhydrous environment. By
exposure to aqueous environments, as in the oral cavity, the
PVP-H.sub.20.sub.2 dissociates into individual species (PVP polymer
and H.sub.20.sub.2). The PVP-H.sub.20.sub.2 complex is generally
comprised of about 80% by weight polyvinyl pyrrolidone and 20% by
weight H.sub.20.sub.2. It also may be useful to have as a part of
the peroxide component an agent to enhance the release of peroxide.
Polypore.RTM. which is an allyl methacrylate crosspolymer available
from Amcol health & Beauty Solutions, Inc. is such an enhancing
agent.
[0025] The peroxide releasing compound is present in the liquid
whitening compositions of the present invention at a concentration
of about 0.5 to about 50% by weight and preferably about 10 to
about 40% by weight.
[0026] Nonionic surfactants which are compatible with peroxide
compounds serve as a solubilizing, dispersing, emulsifing and
wetting agents and are especially effective to solubilize a flavor
if included in the liquid whitening composition. A particularly
useful nonionic surfactant is a water soluble polyoxyethylene
monoester of sorbitol with a C10 to C18 fatty acid, marketed
commercial under the Tween trademark. The Tween surfactants are
mixtures of C10 to C18 fatty acid esters of sorbitol (and sorbitol
anhydrides), consisting predominately of the monoester, condensed
with about 10-30, preferably about 20, moles of ethyleneoxide. The
fatty acid (aliphatic hydrocarbonyl monocarboxylic acid) may be
saturated or unsaturated, e.g., lauric, palmitic, stearic, oleic
acids. Polysorbate 20 (e.g., Tween 20) is especially preferred and
is commonly referred to as polyoxyethylene (20) sorbitan
monolaurate. The nonionic surfactant constitutes about 0 to 50% by
weight and preferably 0.5 to 40% by weight of the liquid
composition.
[0027] The liquid whitening composition of the present invention
may also contain a flavoring agent. Flavoring agents that are used
in the practice of the present invention include essential oils as
well as various flavoring aldehydes, esters, alcohols, and similar
materials. Examples of the essential oils include oils of
spearmint, peppermint, wintergreen, sassafras, clove, sage,
eucalyptus, marjoram, cinnamon, lemon, lime, grapefruit, and
orange. Also useful are such chemicals as menthol, carvone, and
anethole. Of these, the most commonly employed are the oils of
peppermint, spearmint and wintergreen. The flavoring agent is
incorporated in the whitening liquid composition of the present
invention at a concentration of about 0.0 to about 2% by weight and
preferably about 0.1 to about 0.5% by weight.
[0028] A sweetening material may also be employed as an alternative
or complement to the flavoring material. Suitable sweetening agents
are water soluble and include sodium saccharin, sodium cyclamate,
xylitol, perillartien, D-tryptophan, aspartame, dihydrochalcones
and the like, in concentrations of about 0.01 to about 1% by
weight. Sodium saccharin is preferred.
[0029] Other ingredients which are included in the liquid whitening
composition comprise materials commonly used in the oral care
formulations. These include: antimicrobial agents, e.g., Triclosan,
chlorhexidine, copper-, zinc- and stannous salts such as zinc
citrate, zinc sulphate, zinc glycinate, sodium zinc citrate and
stannous pyrophosphate, sanguinarine extract, metronidazole,
quaternary ammonium compounds, such as cetylpyridinium chloride;
bis-guanides, such as chlorhexidine digluconate, hexetidine,
octenidine, alexidine; and halogenated bisphenolic compounds, such
as 2,2' methylenebis-(4-chloro-6-- bromophenol); antiinflammatory
agents such as ibuprofen, flurbiprofen, aspirin, indomethacine;
anticaries agents such as sodium-, calcium-, magnesium- and
stannous fluoride, aminefluorides, disodium monofluorophosphate and
sodium trimetaphosphate; plaque buffers such as urea, calcium
lactate, calcium glycerophosphate and strontium polyacrylates;
vitamins such as Vitamin C; plant extracts; desensitizing agents,
e.g., potassium citrate, potassium chloride, potassium tartrate,
potassium bicarbonate, potassium oxalate, potassium nitrate and
strontium salts; agents effective against dental calculus such as
pyrophosphate salts including the mono, di, tri and tetra alkali
metal and ammonium pyrophosphate and tripolyphosphate salts;
biomolecules, e.g., bacteriocins, antibodies, enzymes such as
papain, glucoamylase; opacifying agents, pigments, coloring agents
and fluoride ion providing salts having anticaries efficacy such as
sodium fluoride, potassium fluoride, a tin fluoride such as
stannous fluoride.
[0030] The liquid whitening compositions of the present invention
are prepared by adding and mixing the ingredients of the
composition in a suitable vessel such as a stainless steel tank
provided with a mixer. In the preparation of the liquid whitening
composition, the ingredients are advantageously added to the mixer
in the following order: liquid anhydrous silicone based pressure
sensitive polymer, peroxide whitening agent, adhesion enhancing
agent and any desired flavoring or sweetener. The ingredients are
then mixed to form a homogeneous dispersion/solution. The moisture
content of the tooth whitening composition will be about 0.05% by
weight to about 10% by weight, and preferably about 2% by weight to
about 8% by weight. The viscosity will be about 50,000 cps to about
900,000 cps and preferably about 200,000 cps to about 600,000
cps.
[0031] The present invention is illustrated by the following
examples but is not to be limited thereby.
EXAMPLES 1-4
[0032] The formulations in the following Table 1 were formed by
adding the silicone hydrophobic polymers Dow Coming Q7-9120 and Dow
Coming 8-7016 in a dimethicone solvent to a Brogli mixer. These two
components were mixed for 30 minutes at high speed without vacuum.
Sodium saccharin was added and mixing continued for 3 minutes at
high speed without vacuum. The COP Plastigel 5 was then added and
mixing continued for 10 minutes at high speed without vacuum. The
Polyplasdoxyl XL10, 35% hydrogen peroxide peralkali and flavor were
added and mixed on a low speed without vacuum for 5 minutes. Full
vacuum then is applied and the formulation is mixed at high speed
for an additional 15 minutes.
2TABLE 1 Example 1 Example 2 Example 3 Example 4 Ingredient (Wt. %)
(Wt. %) (Wt. %) (Wt. %) Dow Corning 30.0 30.0 30.0 30.0 8-7016 Dow
Corning 20.0 16.46 -- 20.0 Q7-9120 Plunacare -- -- -- 0.05 L 1220
Polyplasdone 25.0 25.0 25.0 25.0 XL-10 COP Plastigel 5 20.1 15.5
11.91 (Lyne Labs) 35% Hydrogen 4.0 12.14 44.1 12.14 Peroxide
Peralkali Sodium Saccharin 0.3 0.3 0.30 0.30 VW Mint Flavor 0.6 0.6
0.6 0.60 Viscosity cps 180,000 180,000 270,000 360,000
[0033] The formulations of Examples 1-4 have viscosities of 180,000
cps to 360,000 cps. These formulations were found to have a
workable consistency in being applied to a tray and in adherence to
teeth. There also is a low loss of formulation from the tray by the
natural flushing action of saliva.
EXAMPLE 5
[0034] The formulation of Example 3 was tested in vitro against a
hydrophilic commercial tooth whitening product. Six naturally
stained prophied human teeth were placed into two preformed
thermoplastic trays, custom fitted to the teeth. In one tray was
the formulation of Example 3 along with 3 ml of saliva and in the
other tray was the commercial product and 3 ml of saliva. The
saliva is added to replicate mouth conditions. The formulation of
Example 3 and the commercial product were tested. The Example 3
formulation and the commercial product were placed in separate
trays with the teeth for a period of 1 hour. There were 2
applications of the formulation and the product to the teeth. After
each 1 hour period the teeth were rinsed with deionized water and
maintained in contact with deionized water. There was a period of
10 minutes between each treatment.
[0035] Table 2 gives the data from statistical analysis of the
bleach action on the test teeth as noted by the color change after
2 treatments for 1 hours each. The tests were conducted on a
Minolta CR-321 chromometer based on initial L, a and b CIELAB
values. The L, a and b values were measured four times at differing
locations on the surface of the teeth. The average initial and the
final chromometer were used to calculate delta E according to
(formula). The final delta E was the average over all observations
after the rejection of outliersusing the Students test (95%
confidence level). The product of Example 3 produces the greater
color change to the teeth.
3TABLE 2 Color Change after 5 Treatments (15 hours) Product
.DELTA.L .DELTA.b .DELTA.E Commercial 4.0 -4.4 6.4 Example 3 6.1
-7.0 9.5
[0036] Table 3 shows the consumption of peroxide during a 3 hours
test. The commercial aqueous hydrophilic product consumed 26.7% of
the peroxide while the hydrophilic product of Example 3 consumed
only 8.9% of the peroxide.
4TABLE 3 % Peroxide consumption after 3 hours Initial HP *Final HP
% HP Product Concentration (%) Concentration (%) Consumed
Commercial 3 2.2 26.7 Example 3 4.5 4.1 8.9
[0037] The net result is that the hydrophilic formulation consumes
less peroxide to yield more stain removal. If treatments are
continued for more than 3 hours there will be more peroxide
available (higher concentration) to remove stains and to whiten
teeth.
* * * * *