U.S. patent application number 15/624563 was filed with the patent office on 2018-05-10 for teeth whitening compositions and methods.
The applicant listed for this patent is KLOX Technologies Inc.. Invention is credited to Nikolaos Loupis, Remigio Piergallini.
Application Number | 20180125770 15/624563 |
Document ID | / |
Family ID | 38256668 |
Filed Date | 2018-05-10 |
United States Patent
Application |
20180125770 |
Kind Code |
A1 |
Piergallini; Remigio ; et
al. |
May 10, 2018 |
TEETH WHITENING COMPOSITIONS AND METHODS
Abstract
Disclosed herein are teeth whitening compositions generally
including an oxidizing agent (e.g., a peroxide), and an activating
agent that has an emission wavelength between about 400 nm and
about 570 nm (e.g., Eosin B). Methods of employing these
compositions to whiten teeth, methods of making these compositions
and kits that include some or part of the composition ingredients,
are also described.
Inventors: |
Piergallini; Remigio;
(Grottammare Ascoli Piceno, IT) ; Loupis; Nikolaos;
(Athens, GR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KLOX Technologies Inc. |
Laval |
|
CA |
|
|
Family ID: |
38256668 |
Appl. No.: |
15/624563 |
Filed: |
June 15, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14541714 |
Nov 14, 2014 |
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15624563 |
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13484151 |
May 30, 2012 |
8986719 |
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14541714 |
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13296007 |
Nov 14, 2011 |
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13484151 |
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11598206 |
Nov 9, 2006 |
8075875 |
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13296007 |
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60735072 |
Nov 9, 2005 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61K 2800/434 20130101;
A61Q 11/00 20130101; A61K 2800/43 20130101; A61K 8/22 20130101;
A61K 8/498 20130101; A61K 2800/81 20130101 |
International
Class: |
A61K 8/49 20060101
A61K008/49; A61Q 11/00 20060101 A61Q011/00; A61K 8/22 20060101
A61K008/22 |
Claims
1. A tooth whitening composition comprising: an oxidizing agent;
and an activating agent having an emission wavelength between about
400 nm and about 570 nm.
2-20. (canceled)
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to teeth whitening
compositions. More specifically, the invention relates to teeth
whitening compositions and kits that can be employed to provide a
desired whitening effect (e.g., at least two shades of whitening)
in less than 20 minutes (e.g., about 1 minute) without significant
post-treatment sensitivity.
BACKGROUND OF THE INVENTION
[0002] Peroxide and peroxyacid compounds, such as hydrogen peroxide
and carbamide peroxide, have been disclosed as useful in teeth
whitening compositions. Application of UV or visible light from,
e.g., Argon lasers, has been employed to accelerate whitening after
application of peroxide compositions to the teeth. Additionally,
whitening compositions have been described that include compounds
capable of absorbing light and converting it to heat or chemical
energy, such as the metal-ligand complexes and metal chelate
precursors described in U.S. Pat. No. 6,343,933 to Montgomery et
al.
[0003] Red dyes have also been employed to absorb visible or UV
energy and produce heat in a bleaching composition as described,
e.g., in U.S. Pat. No. 6,485,709 to Banerjee et al. This patent
also describes attempts to further enhance such compositions by
adding metal ions, an organo-metallic enzyme (e.g., catalase), or
using high pH (e.g., above 7) to destabilize or activate the
decomposition of hydrogen peroxide. Teeth whitening compositions
have also been described that include violet or blue-violet dyes to
counter-stain yellow teeth in U.S. Pat. No. 6,030,222 to Tarver.
Rhodamine B dye has been employed in a teeth whitening composition
as described in WO 02/22097 to Verheyen et al.
[0004] Tooth sensitivity following treatment, and the time required
for teeth whitening compositions (typically requiring about an hour
of time or multiple applications or both), however, remains a
significant drawback.
SUMMARY OF THE INVENTION
[0005] The present invention provides novel compositions and
methods that whiten teeth in a surprisingly short amount of time
(e.g., about 1 to 10 minutes) and with minimal or no sensitivity
post-treatment. The invention is based, in part, on the discovery
that the use of the dyes described herein dramatically accelerates
the whitening process.
[0006] Without wishing to be bound to any particular theory, it is
believed that inclusion of these dyes significantly enhances the
compositions of the invention at least because it is believed that
dentin transmits green light and absorbs blue light. Accordingly,
the dyes of the present invention enhance whitening not only at the
surface of the tooth, but also may be transmitting light into the
tooth to enhance the alteration of color agents by radicals that
have penetrated into the tooth surface.
[0007] Another advantage of the present invention is that the
compositions can be effective when applied only for a short period
of time (e.g., 1 minute in some embodiments). Accordingly,
sensitivity due to, e.g., percolation of hydrogen peroxide to the
pulp tissue causing (e.g., pulpal inflammation), may be minimized
or eliminated. Another advantage of the present invention is that
the compositions do not require compounds that generate heat, and
therefore, discomfort associated with compositions that generate
heat may be minimized or eliminated. Yet another advantage is that
dyes can be used (e.g., Eosin B) that are less toxic than dyes such
as Rhodamine B.
[0008] In one aspect, the present invention features a tooth
whitening composition which includes an oxidizing agent and an
activating agent having an emission wavelength between about 400 nm
and about 570 nm.
[0009] In one embodiment, the activating agent is capable of
emitting green light, blue light or blue-green light, and/or
absorbs green light, blue light or blue-green light. In another
embodiment, the activating agent comprises Eosin B, Erythrosin B,
or both.
[0010] In another embodiment, the composition further includes a
stabilizing agent. In one embodiment, the stabilizing agent is
sodium acetate.
[0011] In one embodiment, the composition further includes a
thickening agent. In one embodiment, the thickening agent is
silicon dioxide and/or fumed silica having a particle size less
than one micron.
[0012] In one embodiment, the composition further includes a
hydrophilic gelling agent. In another embodiment, the composition
further includes an accelerator agent. In some embodiments, the
accelerator agent includes sodium perborate.
[0013] In one embodiment, the pH of the composition is between
about 8 and about 10.
[0014] The invention also features a method for tooth whitening
including applying the tooth whitening composition of the present
invention to at least one tooth, and exposing the tooth whitening
composition to actinic light such that the tooth is whitened at
least about one shade. In one embodiment, the tooth is whitened at
least about two shades in less than about 10 minutes or in less
than about 5 minutes.
[0015] In one embodiment, post-treatment sensitivity is
insignificant or eliminated.
[0016] In one embodiment, the tooth is exposed to the tooth
whitening composition for less than 5 seconds per application.
[0017] The invention also features a kit for tooth whitening
including a tooth whitening composition of the invention and an
apparatus for preparing and/or applying the composition.
[0018] The invention also features a kit for tooth whitening
including a tooth whitening composition of the invention and
instructions for determining a composition application time to
achieve a desired whitening effect.
[0019] The invention also features a method for tooth whitening
including at least one application of actinic light and a tooth
whitening composition to at least one tooth such that the tooth is
whitened at least about two shades with less than about 1 minute of
total exposure to actinic light. In one embodiment, the tooth is
whitened at least about three shades in less than about 30 seconds.
In another embodiment, there is no significant post-treatment
sensitivity.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] In order to more clearly and concisely describe the subject
matter of the claims, the following definitions are intended to
provide guidance as to the meaning of specific terms used in the
following written description, examples and appended claims.
[0021] The term "accelerating agent" refers to any agent capable of
accelerating and/or contributing to the completion of radical
generation (e.g., sodium perborate).
[0022] The term "actinic light" refers to light energy capable of
being absorbed by an activating agent.
[0023] The term "activating agent" refers to any agent capable of
absorbing actinic light. Preferably, the activating agent enhances
and/or accelerates the dispersion of light energy, or otherwise
enhances and/or activates the decomposition of an oxidizing agent.
Activating agents include agents capable of absorbing light energy
and emitting light energy, e.g., fluorochromes. Suitable activating
agents include, e.g., Eosin B and Erythrosin B.
[0024] The term "oxidizing agent" refers to any agent capable of
oxidizing, and also includes precursors of compounds capable of
oxidizing. Examples of oxidizing agents includes, but are not
limited to, peroxide, peroxy acid, hydrogen peroxide, carbamide
peroxide, alkali metal peroxides, alkali metal percarbonates,
peroxyacetic acid, and alkali metal perborates.
[0025] The term "post-treatment sensitivity" refers to sensitivity
or instant pain experienced by a subject after a tooth whitening
procedure. Sensitivity can include, but is not limited to, stimuli
such as temperature and pressure. Instant pain typically occurs
without stimuli. The terms "significant sensitivity" or
"significant post-treatment sensitivity" and the like, refer to
significant discomfort post-treatment, including sensitivity and/or
instant pain for more than four hours. The term "insignificant
pain" refers to minimum sensitivity to stimuli such as temperature
and/or pressure for less than four hours post-treatment.
[0026] The term "stabilizing agent" refers to any agent that
stabilizes one or more agents of the composition (e.g., an
oxidizing agent such as hydrogen peroxide). The stabilizing agent
can act to stabilize the agent or agents against spontaneous or
unwanted reactivity in use and/or in storage. Suitable stabilizing
agents include sodium acetate. In some instances, the stabilizing
agent can stabilize hydrogen peroxide for about one year.
[0027] The term "total exposure to actinic light" refers to the
total time a tooth is exposed to actinic light including multiple
applications of actinic light over the course of a treatment
session.
[0028] The term "transparent" refers to a composition capable of at
least 70% transmission of light. The term "translucent" refers to a
composition capable of at least about 40% transmission of light.
The light referred to can be, e.g., actinic light (e.g., from a
laser), emitted light (e.g., from a fluorochrome), or both.
[0029] The term "translucency agent" refers to any agent capable of
increasing the translucency of a composition. Such agents can
increase translucency, e.g., upon addition to the composition, upon
activation (e.g., by heat, actinic light and/or emitted light), or
both.
[0030] When ranges are disclosed herein (e.g., wavelength, pH,
concentration, particle sizes, and whitening ranges) all individual
values and ranges within the disclosed ranges are regarded as part
of and encompassed by the present invention. All concentrations are
provided in weight % of the composition unless indicated
otherwise.
[0031] Where "a", "an" or the like is used herein, these articles
are used in the open or non-restrictive sense, e.g., to indicate
"at least one" or "one or more." Similarly, the term "or" is used
in the open or nonrestrictive sense, i.e., to mean "and/or."
Accordingly, the terms "or" and "and/or" are used interchangeably
and are meant to have the same meaning.
[0032] In one aspect, the present invention provides tooth
whitening compositions that include an oxidizing agent (e.g.,
hydrogen peroxide), and an activating agent that has an emission
wavelength between about 400 nm and about 570 nm (e.g., Eosin B or
Erythrosin B or both). The composition can also include additional
agents including, but not limited to, pH adjusting agents,
thickening agents, stabilizing agents, accelerating agents, gelling
agents, translucency agents.
[0033] The oxidizing agent can be any oxidizing agent known in the
art. In one embodiment, the oxidizing agent includes hydrogen
peroxide or sodium perborate or both. Additionally or
alternatively, the oxidizing agent can include carbamide peroxide,
alkali metal peroxides, alkali metal percarbonates, alkali metal
perborates or combinations of these compounds. The oxidizing agents
can be, e.g., liquid, gel, or paste compositions capable of
interacting with the activating compound when exposed to actinic
light.
[0034] The concentration of the oxidizing agent can be varied in
the present invention. In one embodiment, the oxidizing composition
includes a hydrogen peroxide, e.g., in a range of about 1% to about
70%. In a further embodiment, the oxidizing composition includes
about 50% hydrogen peroxide.
[0035] The activating agent can include any agent with an emission
wavelength between about 400 nm and about 570 nm. In another
embodiment, the activating agent emits light in the range of
between about 435 nm and about 520 nm. In one embodiment, the
activating agent emits light in the range of between about 520 nm
and about 565 nm. In certain embodiments, the agent both absorbs
and emits light in the above ranges. In one embodiment, the
activating agent emits green light. In another embodiment, the
activating agent emits blue-green light. In one embodiment the
activating agent both absorbs and emits green light.
[0036] In one embodiment, the activating agent includes Eosin B or
Erythrosine B or both. In another embodiment, the whitening
composition includes in the range of about 0.5% to about 0.8%, or
between about 0.2% and about 1.2%, or less than about 12%, of Eosin
B. In yet another embodiment, the composition includes about 0.2 to
about 12% of Eosin B and from about 0.01 % to about 0.1%, or about
0.005% and about 0.15%, of Erythrosine B. Without wishing to be
bound to any particular theory it is believed that the combination
of Eosin B and Erythrosine B has a synergistic effect. It is
believed this synergistic effect may be related to the close
absorption peaks of the dyes. It is further believed that because
Eosin B and Erythrosine B re-emit green light, that this green
light can and may be further absorbed (or re-absorbed) by the
fluorochromes so that light energy is not dissipated as in
conventional compositions. This absorbed and re-emitted light not
only penetrates throughout the bleaching gel, but also is
transmitted into the enamel and dentin. Dyes such as Eosin B are
also advantageous as they are significantly less toxic than dyes
such as Rhodamine B.
[0037] Without wishing to be bound to any particular theory, it is
believed that because dentin and enamel transmit green light, light
in this range can be transmitted into the dentin and/or enamel of
the tooth, causing excitation of electrons in specific chemical
bonds within the activating agent and tooth chromaphores, making
them more susceptible to be attacked by free radicals. The
activating agents of the invention can include blue-green and/or
blue emitting dyes. Accordingly, the present invention is based, at
least in part, on the discovery that the use of the activating
agents of the invention significantly enhance and/or contribute to
the enhancement of a whitening effect in a fraction of the time
required by conventional compositions. Because the teeth are only
exposed to the whitening composition for a fraction of the time as
compared to conventional teeth whitening compositions, superficial
cracks and crevices, caused by prolonged exposure to free radicals,
can be reduced or eliminated. Because decalcification can occur in
the cracks and crevices caused by prolonged exposure to free
radicals, stains more easily return as the decalcified enamel acts
as a sponge. In the present invention, the decreased exposure time
to free radical reduces the possibility of crevices and cracks,
thus leading to a significantly prolonged or permanent whitening
effect for deeper pigments. Moreover, prolonged periods of exposure
cause the enamel to become brittle. It is believed that the
composition and methods of the present invention avoid compromise
of the enamel.
[0038] In one embodiment, the activating agent or agents not only
are capable of emitting light in the wavelength range from about
400 nm to about 570 nm, but also absorb light in the wavelength
range from about 400 nm to about 570 nm. Such an activating agent
is activated by light in the wavelength range of from about 400 nm
to about 570 nm. Accordingly, in one embodiment the activating
agent absorbs light in the wavelength range of about 400 nm to
about 570 nm. In another embodiment, the activating agent absorbs
light at a wavelength between about 470 nm to about 550 nm. This
embodiment therefore allows for the optimal absorption of energy
from the actinic light and the optimal transmission through dentin
and enamel.
[0039] Without wishing to be bound to any particular theory, it is
also believed that activating agents of the present invention, when
exposed to actinic light, can accelerate the dispersion of light
energy which consequently leads to an instantaneous and complete
photochemical activation of the peroxide within the gel. It is
believed that the gel mass better transmits light in the wavelength
range of about 400 nm to about 570 nm, so that when an activating
agent is exposed to actinic light, the dispersion of the light
energy leads to an accelerated photochemical activation of the
peroxide. Together, these embodiments allow for optimal absorption
by the activating agent of energy from the actinic light and the
optimal transmission through the composition, dentin and
enamel.
[0040] In one embodiment, the composition also includes a
stabilizing agent. In one embodiment, the stabilizing agent
stabilizes the peroxide concentration in the composition for days,
weeks, months, a year or several years. In one embodiment, the
stabilizing agent not only stabilizes the oxidizing agent, but also
is a pH modifier and/or stabilizer. In another embodiment, the
stabilizing agent is sodium acetate. In one embodiment, sodium
acetate is added until the desired pH is attained. In yet another
embodiment, the composition includes between about 0.1% and about
50% stabilizing agent. Any value or range within this range is
meant to be encompassed.
[0041] In one embodiment, the stabilizing agent is selected from
the group consisting of antioxidants such as sodium sulfite, metal
chelators (e.g., EDTA), and stabilizers (e.g., tin salts,
phosphoric acid, and tin sulphonates). In some embodiments, the
stabilizing agent scavenges or otherwise isolates or removes from
solution, metal ions that can potentially destabilize the hydrogen
peroxide.
[0042] In one embodiment, the stabilizing agent is or includes
sodium acetate (e.g., sodium acetate trihydrate). Sodium acetate
has been found to inhibit spontaneous reactivity of hydrogen
peroxide and therefore can provide improved stability.
[0043] In one embodiment, the pH of the composition is in or
adjusted to the range of from about 4 to about 10. In alkaline
conditions, with a pH from about 8 to about 10, the stronger free
radical, perhydroxyl ions, can be generated. Perhydroxyl free
radicals are capable of reacting not only with yellow and brown
stains but even with grey chromophores situated deeper in the tooth
structure. In further embodiments, the pH of the composition is
between about 5 and about 7, or between about 5 and about 6. In
certain embodiments the pH is about 6.
[0044] Suitable pH adjusting agents include, but are not limited
to, sodium hydroxide, potassium hydroxide, ammonium hydroxide,
sodium carbonate, potassium carbonate, TRIS, and triethanolamine,
or any other salt of an alkaline base which is safely used in the
mouth. In another embodiment, the pH adjusting agent is sodium
perborate. In certain embodiments of the invention, a single
component may act as a pH adjusting agent or as a stabilizing agent
or may serve both functions. In one embodiment, sodium acetate acts
as a pH adjusting agent and as a stabilizing agent. In further
embodiments, the pH adjusting agent is of the group consisting of
sodium bicarbonate, calcium bicarbonate, sodium carbonate and
calcium carbonate.
[0045] Additionally or alternatively, the composition can include a
thickening agent to improve the ease of application of the
composition to the teeth such that even and effective coverage is
more readily achieved. Suitable thickening agents include but are
not limited to mixed silica-aluminum oxides, long chain
hydrocarbons such as synthetic carbomers (e.g., Carbopol),
triethanolamine (e.g., Trolamine), and water soluble poly (ethylene
oxide) resins (e.g., Polyox). Suitable thickening agents also
include amide starches.
[0046] It has been found that using an agent which has a particle
size in the range from about 0.2 microns (.mu.m) to about 0.7 .mu.m
provides for more widespread dispersion of the oxidizing agent on
the particle surface. Accordingly, in one embodiment, the
activating agent has a particle size below about 2 microns or below
about 1 micron. In other embodiments, the agent has a particle size
below about 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, or 0.2 microns. In other
embodiments, the activating agent has a particle size between about
0.1 and about 0.8, between about 0.2 and about 0.7, or between
about 0.3 and about 0.6 microns.
[0047] Additionally or alternatively, the thickening agent can
include fumed silica and/or any other inert inorganic material that
may be used as a carrier and can aid in the delivery of active
oxygen to the tooth surface. Fumed silica of a small particle size
(e.g., between about 0.2 microns and about 0.4 microns), can
provide efficient dispersion of hydrogen peroxide and reflection of
light energy within the oxidizing composition.
[0048] In some embodiments, the compositions of the invention
include a reaction accelerator or accelerating agent. In one
embodiment, the composition includes sodium perborate. Sodium
perborate has selective reactivity with hydrogen peroxide in
forming free radicals (reacts with water to release hydrogen
peroxide). The use of one or more activating agents (e.g., sodium
perborate) can be advantageous because they can absorb and retain
heat generated in the composition by, e.g., actinic light, thus
restricting any such heat to the gel in order to accelerate the
reaction without heating the tooth, which can cause sensitivity. In
addition, acceleration of the reaction means that the composition
can be removed more quickly than conventional compositions thereby
decreasing exposure of the patient to the composition and resulting
sensitivity and/or other damage to tissues and teeth.
[0049] In one embodiment, the compositions of the invention include
between about 0.8% and about 15%, or between about 0.3% and about
18% accelerator agent.
[0050] In further embodiments, the compositions of the invention
include a gelling agent. Preferably the gelling agent is also a
translucency agent. For example, a hydrophilic gelling agent can be
employed to increase the translucency of the resulting composition
or gel.
[0051] In some embodiments, the nature of the gelling agent (e.g.,
its hydrophilic nature) prevents vaporization of the gel when
exposed to actinic light, thus improving hydration of the coated
tooth area. Increased hydration of the teeth and surrounding
tissues is associated with decreased discomfort and sensitivity. In
one embodiment, the gelling agent can include, for example, one or
more modified starches and/or glucose. In one embodiment, modified
starches and/or glucose are activated in cold water. In some
embodiments, the gelling agent further enhances the consistency of
the composition, facilitating the application to the tooth
surface.
[0052] The translucency agent can enhance translucency or
transparency upon addition to the composition and/or upon
activation by, e.g., actinic light, emitted light and/or heat. In
one embodiment, it minimizes vaporization of the composition.
Additionally or alternatively, the gelling and/or translucency
agent minimizes any thermal effects by absorbing any heat generated
in the composition.
[0053] In one embodiment the composition is a translucent
composition. In another embodiment the composition is a transparent
composition. In certain embodiments, the composition is translucent
or transparent to the actinic light it will be exposed to (e.g.,
green, blue-green or blue light).
[0054] In one embodiment, the composition includes an oxidizing
agent (e.g., hydrogen peroxide), an accelerating agent (e.g.,
sodium perborate) an activating agent (Eosin B or Erythrosin B or
both), a stabilizing agent (e.g., sodium acetate trihydrate), a pH
adjusting agent, a thickening agent (e.g., fumed silica or silicon
dioxide or both), and a gelling agent. In one embodiment, the pH of
the composition is from about 6 to about 10. In some embodiments,
the pH of the composition is from about 8 to about 10.
[0055] Another aspect of the invention providers a method for tooth
whitening including applying a tooth whitening composition of the
present invention to at least one tooth, and exposing the tooth
whitening composition to actinic light to activate the oxidizing
agent. The composition may be any of the compositions described
herein.
[0056] In one embodiment, the method for bleaching the teeth is
performed in a dentist's office or dental operatory under ordinary
conditions. The composition can be mixed chair-side and applied to
the surfaces of as many teeth as are desired to be whitened.
Alternatively, the composition can be provided without the need for
mixing chair-side. Thereafter, the composition can be exposed to
actinic light to accelerate decomposition of the oxidizing agent
and the formation of free radicals. In one embodiment, premixes can
be prepared with some or all of the ingredients and then mixed
chairside and applied to the teeth. In one embodiment, a hydrogen
peroxide/sodium acetate solution premix cars be prepared and stored
prior to use. Additionally or alternatively, some or all of the
remaining ingredients can also be separately premixed and stored
prior to use. Such premixes can be stored, e.g., for at least about
one year.
[0057] The compositions of the invention can be used to whiten
teeth discolored by any agent or disorder. For example, she
compositions may be used to whiten discoloration due to stains
(e.g., tobacco, coffee, tea and/or food stains), fluorosis,
developmental disturbances, bacteria, genetics, tetracycline
antibiotics, trauma, blood decomposition, pigments present during
development of teeth, etc.
[0058] Any source of actinic light can be used and preferably it is
capable of emitting light in a wavelength appropriate to the
activating agent employed in the composition. In one embodiment,
e.g., an argon laser is used. In another embodiment, a
potassium-titanyl phosphate (KTP) laser (e.g., a GreenLight.TM.
laser) is used as a light source. In one embodiment the light
source emits light at or near the absorption wavelength of the
activating agent or at least one of the activating agents, if
several are included in the composition.
[0059] The most intense fluorescence (e.g., emission) from a
fluorochrome dye occurs when it is irradiated with wavelengths
close to the peak of the absorption wavelength (i.e., excitation
curve). Accordingly, in one embodiment, the actinic light is at a
wavelength of about the absorption wavelength of the activating
agent. In one embodiment, the actinic light has a wavelength in the
range from about 470 nm to about 550 nm. In another embodiment, the
actinic light has a wavelength in the range from about 470 nm to
about 520 nm. In yet another embodiment, an argon laser provides
actinic light in the wavelength range from about 470 nm to about
520 nm. In a further embodiment, the actinic light has a wavelength
of about 530 nm to about 535 nm. In still another embodiment, the
source of actinic light in the wavelength range of about 530 nm to
about 535 nm is a KTP laser. In this embodiment the source is a KTP
laser set at about 532 nm. In another embodiment, a photocuring
device is the source of actinic light.
[0060] In one embodiment, the tooth is exposed to actinic light for
less than 20 minutes, in another for less than 10 minutes, in
another for less than 5 minutes. In one embodiment the tooth is
exposed to actinic light for less than 4, 3, 2, or 1 minute. In one
embodiment, the invention provides a method for whitening teeth at
least 2 shades in about 1 minute. In some embodiments, there is no
significant post-treatment sensitivity. In other embodiments, there
is no post-treatment sensitivity.
[0061] In one embodiment, the tooth whitening composition is
applied and the tooth is exposed to multiple applications of
actinic light, for a time of about 4 to about 6 seconds each tooth
per exposure. In some embodiments, the tooth is exposed to actinic
light at least two, three, four, five or six times. In some
embodiments, a fresh application of the tooth whitening composition
is applied before each exposure to actinic light. In some
embodiments, the total exposure to actinic light is less than about
one minute. In other embodiments, the total exposure to actinic
light is less than about 60, 40, 30, or 20 seconds.
[0062] In one embodiment, the tooth is whitened at least 7 shades,
6 shades, 5 shades, 4 shades, 3 shades, 2 shades or 1 shade. Shades
can be determined before and after treatment using any of a number
of shade guides, including, e.g., the VITA.RTM. (Vita Zahnfabrik H.
Rauter GmbH & Co., KG), CHROMASCOP.RTM. (Ivoclar Vivadent,
Inc.) or BIODENT (Dentsply Internatinal) shade guides. Optionally,
a shade taking system, e.g., the ShadeEye NCC Dental Chroma Meter,
can be employed to determine shade before and/or after
treatment.
[0063] In one embodiment, the tooth is whitened at least two
shades, three shades, four shades, five shades, six shades or seven
shades in less than about one minute of total exposure time to
actinic light. In some embodiments, the tooth is whitened at least
two shades, three shades, four shades, five shades, six shades or
seven shades in less than about 40 seconds of total exposure time
to actinic light. In some embodiments, the tooth is whitened at
least two shades, three shades, four shades, five shades, six
shades or seven shades in less than about 30 seconds of total
exposure time to actinic light. In some embodiments, the tooth is
whitened at least two shades, three shades, four shades, five
shades, six shades or seven shades in less than about 20 seconds or
even less than about 10 seconds of total exposure time to actinic
light.
[0064] In one embodiment, the risk of transient inflammation of the
pulp by percolation of hydrogen peroxide is reduced, not
significant and/or eliminated. Without wishing to be bound by any
particular theory, inflammation of the pulp is thought to be caused
by percolation of hydrogen peroxide into the pulp tissue. In some
embodiments, the synergistic effect of the activating agents (e.g.,
Eosin B and Erythrosin B), and the actinic light results in an
instantaneous and complete photochemical reaction. Accordingly,
exposure of the tooth, the pulp, and/or the surrounding tissues to
the oxidizing agent and/or other components in the composition is
dramatically reduced.
[0065] In yet another aspect, the invention provides a method for
tooth whitening comprising application of actinic light and a
composition of the invention (any of the compositions described
herein) to at least one tooth such that the tooth is whitened at
least about two shades in less than about 10 minutes. In another
embodiment, the tooth is whitened at least about two shades in less
than about 5 minutes, less than about 4 minutes, less than about 3
minutes, less than about 2 minutes or in about 1 minute. In some
embodiments, the teeth are whitened at least about 3 shades, 4
shade or 5 shades. In some embodiments, there is no significant
post-treatment sensitivity or no post-treatment sensitivity.
[0066] In yet another aspect, the invention provides a kit for
preparing or applying a tooth whitening composition in accordance
with the present invention. In one embodiment, the kit includes an
oxidizing agent and an activating agent that has an emission
wavelength between about 400 nm and about 570 nm. The composition
can be any of the compositions of the present invention. In one
embodiment, the composition is not combined, and may optionally
include apparatus to combine two or more components or premixes of
the composition. In another embodiment the composition does not
require any combination (i.e., it is ready to use and does not
require any pre-mixing chair-side).
[0067] In another embodiment, the kit includes a composition of the
invention and directions for application. Additionally or
alternatively, the kit can include apparatus for application (e.g.,
brushes or trays or both). The kit can also include charts or other
information helpful in assessing the whitening effect desired
and/or achieved by the methods and compositions of the invention.
The kit can also include a source of actinic light.
[0068] Identification of equivalent compositions, methods and kits
are well within the skill of the ordinary practitioner and would
require no more than routine experimentation, in light of the
teachings of the present disclosure. Practice of the invention will
be still more fully understood from the following examples, which
are presented herein for illustration only and should not be
construed as limiting the invention in any way.
EXAMPLE 1
Preparation of an Exemplary Whitening Composition and Activation by
Actinic Light
[0069] A premix was prepared by mixing 4 mg of Eosin B, 1 mg
Erythrosine B, 450 mg fumed silica, and 45 mg sodium perborate.
Separately, the pH of a 5% hydrogen peroxide solution was adjusted
to pH 6 using sodium acetate solution. Approxmately 4-6 ml of the
adjusted hydrogen peroxide solution was then added to the premix in
a plastic mixing chamber and immediately applied.
[0070] The gel was applied to frontal surface of the teeth of each
subject beginning from the frontal anterior incisors, followed by
the posteriors, and finally the posterior incisors. The gel was
activated by a KTP laser set at a continuous wave of 0.5 watts. The
laser was applied to each tooth for 2-3 seconds. During this time,
the gel turned from orange-red to transparent and eventually became
dull. After 3-4 minutes for two full arches from premolar to
premolar, the gel was aspirated, and the teeth were lightly
scrubbed with a cotton roll to clean the surface of the enamel. A
second coating of gel was applied using fresh gel and activated
with the KTP laser as described above. Up to six consecutive
applications were performed to achieve the desired whitening effect
for each patient. The duration of the sessions typically did not
exceed 40 minutes.
COMPARATIVE EXAMPLE 2
Whitening Effect of Composition
[0071] A comparative study was conducted on 10 volunteers between
an exemplary composition of the present invention and the
SMARTBLEACH laser teeth whitening systems, which is a composition
comprising Rhodamine B and hydrogen peroxide. The shade of each
patient's teeth was recorded prior to application of whitening
composition.
[0072] Teeth were coated with the composition prepared in Example 1
and exposed to actinic light from a green laser set at 532 nm for
one minute for the entire mouth (4-5 seconds per tooth) and then
the composition was removed. The comparative composition was
applied to the teeth and exposed to light from a green laser set at
532 nm for 30 seconds per tooth and then left on the surface of the
tooth for 10 minutes, in accordance with the manufacturer
instructions provided with the composition. The comparative
composition required at least 3 to 4 applications, for a total
duration of about 1.5 hours for the entire mouth. The composition
was removed from each volunteer and the teeth were irrigated with
water. The teeth were then evaluated using the VITA scale for the
whitening effect of the compositions. Patients were also evaluated
for any post-treatment sensitivity by asking them to rate the level
of pain experience if any.
[0073] The Smartbleach.TM. treatment resulted in a shade change of
one to two shades to the yellow group, while the exemplary
composition of the present invention resulted in a shade change of
5 shades in the yellow group, e.g., A.sub.4 to B.sub.1 VITA scale.
In the "yellow group" (A.sub.4-A.sub.1), treatment with the
exemplary composition of the present invention resulted in shade
changes of 4-5 shades, resulting in shades in the "white group"
(B.sub.1-B.sub.2). Treatment with the exemplary composition for
teeth in the "grey" (C.sub.4-C.sub.1) and "grey-brown"
(D.sub.4-D.sub.2) groups showed changes of 2-3 shades in the first
session.
[0074] The following evaluation scale of post-sensitivity was
used:
TABLE-US-00001 Level 0 No sensitivity to thermal stimuli or any
kind of pain following treatment. Level 1 Sensitivity to thermal
stimuli that lasts for a few seconds. Level 2 Pain or discomfort
that occurs due to thermal stimuli and lasts for more than one
minute. Optional pain treatment with analgesies. Level 3 Pain or
discomfort that occurs automatically, requiring use of analgesics
to control the pain.
[0075] Following treatment with the Smartbleach.TM. system, all ten
subjects experienced pain from Level 1 to Level 3. Following
treatment with the exemplary composition of the present invention,
nine subjects experienced no pain (e.g., Level 0), and only one
subject experienced pain of Level 1.
COMPARATIVE EXAMPLE 3
Effect of Actinic Light Source
[0076] A study was conducted on 28 volunteers comparing the effect
of different actinic light sources in whitening with the
composition of Example 1. A prophylactic session was performed on
each patient 3-4 days before the bleaching session. The shade of
each patient's teeth was recorded prior to application of whitening
composition.
[0077] Teeth were coated with the composition prepared in Example 1
and exposed to different sources of actinic light: a green laser
(KTP) at 532 nm, a blue (argon) laser at 480-414 nm, a photocuring
halogen lamp, and a LED photocuring device.
[0078] The activation was performed in the different patients for
the left or the right sides of their dental arches according to an
activation randomization mode. Specifically, a first patient's
right side was activated with the 532 nm green laser, while the
left side was activated with the 480 nm-514 nm blue-green laser. A
second patient's right side was activated with the photocuring
halogen lamp, while the left side was activated with the LED
photocuring device. A third patient's right side was activated with
the 532 nm green laser, while the left side was activated with the
photocuring halogen lamp. A fourth patient's right side was
activated with the 532 nm green laser, while the left side was
activated with the LED photocuring device. A fifth patient's right
side was activated with the 480 nm-514 nm blue-green laser, while
the left side was activated with the photocuring halogen lamp. A
sixth patient's right side was activated with the 480 nm-514 nm
blue-green laser, while the left side was activated with the LED
photocuring device.
[0079] The composition was removed from the teeth of each volunteer
and the teeth were irrigated with water. The teeth were then
evaluated using the VITA scale for the whitening effect of the
compositions.
[0080] Activation by different photocuring devices produced
comparable results. The speed of activation with the green laser
and the blue-green laser was 4-5 seconds per tooth, white the speed
of activation with the photocuring devices was about 10 seconds per
tooth. Accordingly, a whitening session employing the green laser
or the blue-green laser for the entire mouth would typically take
approximately 30 minutes, and a session with a photocuring device
would typically take approximately 40 minutes.
* * * * *