U.S. patent application number 13/825555 was filed with the patent office on 2013-07-25 for oral composition for removing tooth stain.
This patent application is currently assigned to REGENETISS, INC.. The applicant listed for this patent is Shinichi Kato, Yumi Kawazoe, Toshikazu Shiba. Invention is credited to Shinichi Kato, Yumi Kawazoe, Toshikazu Shiba.
Application Number | 20130189200 13/825555 |
Document ID | / |
Family ID | 45873936 |
Filed Date | 2013-07-25 |
United States Patent
Application |
20130189200 |
Kind Code |
A1 |
Shiba; Toshikazu ; et
al. |
July 25, 2013 |
Oral Composition For Removing Tooth Stain
Abstract
[Problem] The object of the present invention is to provide an
oral composition, which can remove tooth stain effectively. The
object of the present invention is also to provide an oral
composition, which scarcely damages teeth and gums and can be
easily applied. [Method of solution] An oral composition for
removing tooth stain, which comprises 3.5 to 30% by weight of
peroxide and 5 to 20% by weight of phosphate polymer (in
particular, ultraphosphate having an average chain length of
phosphoric acid polymerization of 10 to 30).
Inventors: |
Shiba; Toshikazu; (Okaya-shi
Nagano, JP) ; Kawazoe; Yumi; (Okaya-shi Nagano,
JP) ; Kato; Shinichi; (Okaya-shi Nagano, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Shiba; Toshikazu
Kawazoe; Yumi
Kato; Shinichi |
Okaya-shi Nagano
Okaya-shi Nagano
Okaya-shi Nagano |
|
JP
JP
JP |
|
|
Assignee: |
REGENETISS, INC.
Okaya-shi, Nagano
JP
|
Family ID: |
45873936 |
Appl. No.: |
13/825555 |
Filed: |
September 22, 2011 |
PCT Filed: |
September 22, 2011 |
PCT NO: |
PCT/JP2011/071601 |
371 Date: |
April 2, 2013 |
Current U.S.
Class: |
424/53 |
Current CPC
Class: |
A61K 8/24 20130101; A61K
8/42 20130101; A61K 8/86 20130101; A61K 8/84 20130101; A61N 5/062
20130101; A61K 2800/75 20130101; A61K 8/22 20130101; A61C 19/066
20130101; A61Q 11/00 20130101; A61K 2800/81 20130101 |
Class at
Publication: |
424/53 |
International
Class: |
A61K 8/24 20060101
A61K008/24; A61K 8/42 20060101 A61K008/42; A61Q 11/00 20060101
A61Q011/00; A61K 8/22 20060101 A61K008/22 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 23, 2010 |
JP |
2010-212949 |
Claims
1. An oral composition for removing tooth stain, wherein the oral
composition comprises 3.5 to 30% by weight of peroxide and 5 to 20%
by weight of phosphate polymers or a salt thereof.
2. An oral composition in accordance with claim 1, wherein the
phosphate polymer is ultraphosphate.
3. An oral composition in accordance with claim 2, wherein average
chain length of polymerization of the ultraphosphate is 10 to
30.
4. An oral composition in accordance with claim 1, wherein the
peroxide is hydrogen peroxide, calcium peroxide or carbamide
peroxide.
5. An oral composition in accordance with claim 1, wherein pH of
the oral composition is 6.5 to 8.
6. An oral composition in accordance with claim 1, wherein pH of
the oral composition is 6.9 to 7.5.
7. An oral composition in accordance with claim 1, further
comprising an infrared heating substance, and the oral composition
being irradiated by infrared during use.
8. An oral composition in accordance with claim 7, wherein the
infrared heating substance is charcoal.
9. An oral composition in accordance with claim 1, wherein the oral
composition is used at 37 to 50.degree. C.
10. An oral composition in accordance with claim 1, wherein
concentration of the phosphate polymer or its salt is 7.5 to 12.5%
by weight.
11. An oral composition in accordance with claim 1, further
comprising polyethylene glycol.
12. An oral composition in accordance with claim 11, wherein
average molecular weight of the polyethylene glycol is 4000 to
10000.
13. An oral composition in accordance with claim 1 wherein
concentration of the polyethylene glycol is 0.25 to 2% by weight.
Description
TECHNICAL FIELD
[0001] The present invention relates to an oral composition for
removing tooth stain. In particular, the present invention relates
to an oral composition which can remove tooth stain effectively by
containing peroxides and phosphate polymers at a predetermined
concentration.
BACKGROUND ART
[0002] Conventionally, there have been some proposals of oral
compositions for removing tooth stain.
[0003] For example, the pamphlet of International Publication WO
2007/145287 (Patent Document 1) discloses an oral stain remover
containing ultraphosphate. The pH of this oral stain remover is 5
to 6.5 (see paragraph [0024] and [0033] of the document).
[0004] Japanese Unexamined Patent Publication No. 2009-126819
(Patent Document 2) discloses a dental whitening agent containing
hydrogen peroxide or carbamide peroxide as a radical promoter.
[0005] Japanese Unexamined Patent Publication No. 2009-024009
(Patent Document 3) discloses a chewing gum composition for
removing stain from dental surface, which includes peroxides and
polyphosphates.
[0006] Japanese Unexamined Patent Publication (Translation of PCT
Application) No. 2006-504776 (Patent Document 4) discloses a
composition for removing stain from tooth surface, which includes
peroxides and polyphosphates.
[0007] Japanese Unexamined Patent Publication No. 2009-51734
(Patent Document 5) discloses a liquid composition for oral cavity
containing a salt of polyphosphates, acyl taurine salt and
polyethylene glycol, the average molecular weight of which is 600,
and having pH 7 to 9.
PRIOR ART PUBLICATION
Patent Document
[0008] Patent Document 1: International Publication WO
2007/145287
[0009] Patent Document 2: Japanese Unexamined Patent Publication
No. 2009-126819
[0010] Patent Document 3: Japanese Unexamined Patent Publication
No. 2009-024009
[0011] Patent Document 4: Japanese Unexamined Patent Publication
(Translation of PCT Application) No. 2006-504776
[0012] Patent Document 5: Japanese Unexamined Patent Publication
No. 2009-51734
SUMMARY OF INVENTION
Problems to be Solved by the Invention
[0013] Conventional oral compositions can also remove tooth stain.
However, there has been desired to develop an oral composition,
which can remove tooth stain more effectively.
[0014] The object of the present invention is to provide an oral
composition, which can remove tooth stain effectively.
[0015] Furthermore, the oral stain remover of Patent Document 1 may
damage teeth and gums, because it can remove tooth stain only under
acidic conditions. Besides, peroxide also causes great damage to
teeth and gums. Therefore, the object of the present invention is
to provide an oral composition, which scarcely damages teeth and
gums and can be easily applied.
[0016] Furthermore, peroxide dissolves calcium phosphate including
apatite. Namely, the removal of tooth stain by using peroxide
causes dissolution of tooth enamel. Therefore another object of the
present invention is to provide an oral composition, which prevents
dissolution of tooth enamel.
Means for Solving the Problem
[0017] The present invention is on the basis of the findings that
tooth stain can be removed effectively by containing peroxide and
phosphate polymers (in particular ultraphosphate) or its salt at a
predetermined concentration. The present invention is also on the
basis of the findings that tooth stain can be removed effectively
even in neutral pH condition by containing peroxide and the salt of
phosphate polymers at a predetermined concentration.
[0018] A first aspect of the present invention relates to an oral
composition for removing tooth stain. This oral composition
comprises 3.5 to 30% by weight of peroxide and 5 to 20% by weight
of phosphate polymers (preferably ultraphosphate). The average
chain length of polymerization of the ultraphosphate is preferably
10 to 30.
[0019] The oral composition realizes dramatically high removal
effect compared to the cases of using peroxide or ultraphosphate
individually as substantiated in examples. The use of
ultraphosphate also realizes very high removal effect compared to
the case of the other phosphate polymers. Furthermore, the oral
composition has high biocompatibility and high usability, because
it works well under neutral pH condition.
[0020] Examples of the peroxide are hydrogen peroxide, carbamide
peroxide or calcium peroxide.
[0021] The oral composition also works well in a neutral region of
pH 6.5 to 8 (or pH 6.9 to 7.5).
[0022] Preferably, the oral composition further comprises an
infrared heating substance, and is irradiated by infrared during
use. An example of the infrared heating substance is charcoal. The
oral composition can be heated by irradiation of infrared, visible
light including infrared or infrared laser to the charcoal.
Examples of the charcoal are bamboo charcoal, eggplant charcoal and
activated charcoal. The eggplant charcoal is preferable because it
has high biocompatibility and realizes high whitening effect by
synergy effect with peroxide and ultraphosphate.
[0023] Preferably, the oral composition is used at 37 to 50.degree.
C. The oral composition cleans more effectively in this temperature
range because of increase of the peroxide activity. 37 to
45.degree. C. is more preferable temperature range not to hurt
lips, dental pulp and gums by heating.
[0024] Preferably, the oral composition further comprises
polyethylene glycol, as substantiated in the examples. An example
of the average molecular weight of the polyethylene glycol is 4000
to 10000. Preferably, the concentration of the polyethylene glycol
is 0.25 to 2% by weight. The structures mentioned above may be
combined appropriately.
Advantageous Effects of the Invention
[0025] The present invention can provide an oral composition which
can remove tooth stain effectively by containing peroxide and
phosphate polymers (ultraphosphate) at a predetermined
concentration.
[0026] Further, in the present invention, containing phosphate
polymers (in particular, the salt of, ultraphosphate) can provide
an oral composition, which prevents teeth and gums from damage by
peroxide.
[0027] In particular, the oral composition of the present invention
also works well in neutral pH region. Therefore the oral
composition of the present invention scarcely damages organism, and
tooth cleaning operation can be easily performed by using the oral
composition.
[0028] Further, in the present invention, the oral composition
containing ultraphosphate prevents dissolution of calcium phosphate
by peroxide. Therefore, the oral composition of the present
invention effectively prevents dissolution of tooth enamel.
BRIEF DESCRIPTION OF DRAWINGS
[0029] FIG. 1A shows photographs of a tooth, which was treated with
3.5% H.sub.2O.sub.2 in alkaline condition (pH 10) at 42.degree. C.
for each period of time.
[0030] FIG. 1B shows photographs of a tooth, which was treated with
3.5% H.sub.2O.sub.2 in alkaline condition (pH 10) at 42.degree. C.
for each period of time.
[0031] FIG. 2A shows photographs of a tooth, which was treated with
3.5% H.sub.2O.sub.2 and 10% sodium ultraphosphate (pH 7) at
42.degree. C. for each period of time.
[0032] FIG. 2B shows photographs of a tooth, which was treated with
3.5% H.sub.2O.sub.2 and 10% sodium ultraphosphate (pH 7) at
42.degree. C. for each period of time.
[0033] FIG. 3 shows photographs of a tooth, which was treated with
5% H.sub.2O.sub.2 (pH 10) at 42.degree. C. for each period of
time.
[0034] FIG. 4 shows photographs of a tooth, which was treated with
5% H.sub.2O.sub.2 and 10% sodium ultraphosphate (pH 7) at
42.degree. C. for each period of time.
[0035] FIG. 5 shows whitening effect on the same detached teeth
which was coated with 10% H.sub.2O.sub.2 under alkaline condition
and polymers including 10% H.sub.2O.sub.2 and 10% sodium
ultraphosphate under neutral pH condition.
[0036] FIG. 6A shows photographs of a tooth, which was treated with
20% H.sub.2O.sub.2 (pH 10) at 42.degree. C. for each period of
time.
[0037] FIG. 6B shows photographs of a tooth, which was treated with
20% 11202 (pH 10) at 42.degree. C. for each period of time.
[0038] FIG. 7A shows photographs of a tooth, which was treated with
20% H.sub.2O.sub.2 and 10% sodium ultraphosphate (pH 7) at
42.degree. C. for each period of time.
[0039] FIG. 7B shows photographs of a tooth, which was treated with
20% H.sub.2O.sub.2 and 10% sodium ultraphosphate (pH 7) at
42.degree. C. for each period of time.
DESCRIPTION OF EMBODIMENTS
[0040] The oral composition of the present invention is an oral
composition for removing tooth stain. Namely, the oral composition
is mainly used in oral cavity to remove tooth stain. However, the
oral composition of the present invention can be also used to clean
a denture or full denture. An example of the oral composition is
stain remover. This oral composition may be included in toothpaste
or mouse wash and dental rinse. Further, this oral composition may
be liquid or gel form. Furthermore, it may be used in whitening
performed by dentists.
[0041] This oral composition comprises 3.5 to 30% by weight of
peroxide and 5 to 20% by weight of phosphate polymers (preferably
ultraphosphate) or its salt.
[0042] Examples of the peroxide are hydrogen peroxide, calcium
peroxide, carbamide peroxide and calcium peroxide. The
concentration of the peroxide is preferably 3.5 to 20% by weight or
3.5 to 15% by weight, more preferably 3.5 to 10% by weight, and may
be 5 to 10% by weight. Because the cleaning effect of the oral
composition of the present invention becomes higher in these
temperature ranges as shown in examples.
[0043] The oral composition of the present invention comprises
phosphate polymers. An example of the polymers is polyphosphate.
Among polyphosphates, ultraphosphate is preferable. Examples of
ultraphosphate are disclosed in Patent Document 1. A preferable
example of ultraphosphate is ultraphosphate with an average chain
length of which is 10 to 30 phosphate residues. Further, the
average chain length of ultraphosphate may be 15 to 30, and also
may be 15 to 25. In particular, when the average chain length is 15
or more, high whitening effect can be observed by synergy effect
with peroxide. The concentration of phosphate polymers is
preferably 3.5 to 20% by weight, preferably 3.5 to 15% by weight,
more preferably 7.5 to 12.5% by weight, more preferably 3.5 to 10%
by weight, and may be also 5 to 10% by weight.
[0044] The polyphosphate may be added into the composition as a
salt. An example of the salt of polyphosphate is a salt of
polyphosphate and alkali metal including sodium polyphosphate and
potassium polyphosphate.
[0045] This oral composition works well under neutral condition of
pH 6.5 to 8 (or pH 6.9 to 7.5).
[0046] Preferably, the oral composition further comprises an
infrared heating substance, and is irradiated by infrared during
use. An example of the infrared heating substance is charcoal.
Other examples of the infrared healing substance are titanium
oxide, aluminum, gold and silver. Generally, infrared laser or
other light for whitening use are widely equipped in dental
clinics. Further, infrared laser is less harmful than ultraviolet
laser for organism. Irradiation of infrared, visible light
including infrared or infrared laser causes heating of the
charcoal, and then the oral composition including charcoal itself
is heated. Therefore whitening effect of the oral composition is
increased. The oral composition of the present invention can be
used effectively in dental clinic.
[0047] The infrared heating substance means a substance, which
generates heat by irradiation of infrared. Examples of the
wavelengths of the infrared may be 750 to 2000 nm, 800 to 1500 nm,
800 to 1300 nm and 850 to 1050 nm. The present invention also
provides an oral composition, which bleaches tooth by being applied
to the target tooth and irradiated by infrared. The intensity of
the infrared may be 1 to 50 W, 3 to 20 W and 5 to 10 W. The oral
composition of the present invention can also increase its
whitening effect by irradiation of infrared even if the oral
composition does not contain the infrared heating substance.
Namely, the present invention also provides an oral composition,
which contains peroxide at a certain concentration and bleaches
tooth by being applied to the target tooth and irradiated by
infrared.
[0048] Preferably, this oral composition is used at 37 to
50.degree. C. 37 to 45.degree. C. is more preferable temperature
range not to hurt tooth and gums by heating. The oral composition
cleans more effectively in this temperature range because of
increase of the peroxide activity.
[0049] Preferably, the oral composition further comprises
polyethylene glycol, as substantiated in the examples. As shown in
Tables 6 and 10, which will be mentioned below, an example of the
average molecular weight (number average molecular weight) of the
polyethylene glycol is 4000 to 10000. The residual ratio of the
stain can be reduced when the average molecular weight is 4000 or
more. Preferably, the average molecular weight of the polyethylene
glycol is 6000 or more. As shown in Table 6, the residual ratio of
the slain can be dramatically reduced when peroxide, polyphosphate
and PEG exist, because of high degree of synergy effect.
[0050] As shown in Table 7, which will be mentioned below, high
concentration of polyethylene glycol (PEG) does not always bring
about high cleaning ability. Preferably, the concentration of the
polyethylene glycol is 0.25 to 2% by weight. The concentration of
the polyethylene glycol may be 0.5 to 1.5% by weight or 0.75 to
1.25% by weight.
[0051] As shown in Table 9, which will be mentioned below, when
peroxide, polyphosphate and PEG exist, containing 7.5 to 12.5% by
weight of ultraphosphate brings about extremely high cleaning
ability.
[0052] In addition to 3.5 to 30% by weight of peroxide and 5 to 20%
by weight of polyphosphate (preferably, ultraphosphate), the oral
composition may further comprise other compositions used in general
oral composition. For example, the oral composition may comprise
glycerin, fragrances, coloring agents, flavoring agents and
binders. Paste form oral composition can be produced by kneading
and mixing of ingredients. Further, liquid form oral composition
may be produced by dissolving to solution including water or saline
solution.
Example 1
Production of Tea-Stained Dry Apatite as a Colored Tooth Model
[0053] 1 to 2 g of hydroxyapatite (Biogel-HTP, Bio-Rad
Laboratories, Inc.) was put into a 50 mL tube, and 20 mL of protein
solution (1%, IXOS SCP5000, Nitta Gelatin Inc.) was added thereto,
and the mixture was left to stand for 10 to 15 minutes, and then
the mixture was separated by centrifugation at 3,000.times.g for 2
minutes to remove a supernatant. Next, after the centrifugation, 20
mL of stain solution (5 g of instant coffee, two tea bags and two
green tea bags were put into 110 mL of water, and the mixture was
heated by a microwave oven for 2 minutes. Then the mixture was
cooled down at room temperature with shaking for 3 hours to one
night. Then the mixture was filtered by a 200 mesh filter. The
stain liquid was obtained like this.) was mixed with the
precipitated apatite, and the mixture was left to stand for 10 to
15 minutes, and then the mixture was separated by centrifugation
(2,500 rpm, 2 minutes) to remove a supernatant. Then, after
centrifugation, 20 mL of artificial saliva (20 mM HEPES-KOH pH 7.0,
1.5 mM CaCl.sub.2 and 0.9 mM KH.sub.2PO.sub.4) was added into the
precipitated apatite, and the mixture was left to stand for 10 to
15 minutes, and then the mixture was separated by centrifugation
(2,500 rpm, 2 minutes). After removal of a supernatant from the
mixture, the precipitated apatite was dried.
[0054] Whitening Effect Evaluation Test
[0055] 20 mg of the tea-stained dry apatite is weighed, and 0.3 mL
of solution was added thereto, which contains H.sub.2O.sub.2 at
various concentrations and, as appropriate, various phosphate
polymers, NaOH and other substances, and then the mixture was left
to stand at a certain temperature for a certain time. Then the
apatite was precipitated by centrifugation (3,000.times.g, 15
seconds), and a supernatant was removed from the mixture, and then
the apatite was mixed well with 1 mL of water to wash. Further,
subsequent washing procedure was repeated four times. After that,
the apatite was suspended in 200 .mu.L of water, and the suspension
was poured into a well of a 96 well microtiter plate. The 96 well
microtiter plate was scanned from the bottom by a scanner (Epson
GT8300). The image was inverted to be negative, and brightness
analysis was performed by means of imageJ (free software), and then
the residual ratio of stain was calculated.
[0056] Improvement of Whitening Effect by Ultraphosphate
[0057] Table 1 shows the results relating to improvement of
whitening effect of hydrogen peroxide by various phosphate
polymers.
TABLE-US-00001 TABLE 1 Comparison of enhancement of whitening
effect of various phosphate polymers Concent- ration of phos- NaOH
Treat- Residual con- Phos- phate con- ment Treat- ratio cent- phate
poly- cent- temper- ment of ration poly - mers ration ature time
stain (%) mers (%) (N) pH (.degree. C.) (Min.) (%) 0 0 0 7 45
100.00 3.5 Sodium 10 0 7.0 45 10 23.5 ultra- phos- phate 3.5 10 0
7.0 45 10 50.4 indicates data missing or illegible when filed
[0058] Table 1 shows the result of comparison of improvement
ability of whitening effect of hydrogen peroxide by sodium
polyphosphate (average chain length is 80 phosphate residues;
manufactured by Regenetiss Inc.) and sodium ultraphosphate
(manufactured by MITEJIMA CHEMICAL Co., LTD.). Sodium
ultraphosphate has twice or more improvement ability of whitening
effect than sodium polyphosphate.
Example 2
Relationship Between Concentration of Ultraphosphate and
Improvement of Whitening Effect
[0059] Comparison of whitening elect of 3.5% hydrogen peroxide by
using various concentration of sodium ultraphosphate was performed.
In this comparison, pH and temperature are fixed to 7.5 and
42.degree. C., respectively, and whitening effect was compared
after 10 minutes, 30 minutes, 1 hour and 3 hours. The results are
shown in Table 2.
TABLE-US-00002 TABLE 2 Improvement of whitening effect of hydrogen
peroxide in accordance with the concentration of various
ultraphosphate Treat- Ultra- ment Residual phosphate NaOH tem-
ratio concent- concent- concent- per- Treat- of ration ration
ration ature ment stain (%) (%) (N) pH (.degree. C.) time (%) 3.5 0
0 7.5 42 10 98.15 3.5 0 0 7.5 42 30 96.80 3.5 0 0 7.5 42 60 94.89
3.5 0 0 7.5 42 180 88.78 3.5 1 0 7.5 42 10 69.60 3.5 1 0 7.5 42 30
43.56 3.5 1 0 7.5 42 60 24.43 3.5 1 0 7.5 42 180 13.86 3.5 5 0 7.5
42 10 65.82 3.5 5 0 7.5 42 30 22.75 3.5 5 0 7.5 42 60 13.98 3.5 5 0
7.5 42 180 9.06 3.5 10 0 7.5 42 10 68.12 3.5 10 0 7.5 42 30 23.47
3.5 10 0 7.5 42 60 14.28 3.5 10 0 7.5 42 180 9.43 3.5 15 0 7.5 42
10 69.42 3.5 15 0 7.5 42 30 23.61 3.5 15 0 7.5 42 60 14.73 3.5 15 0
7.5 42 180 9.93 3.5 20 0 7.5 42 10 70.30 3.5 20 0 7.5 42 30 23.05
3.5 20 0 7.5 42 60 14.02 3.5 20 0 7.5 42 180 10.10 indicates data
missing or illegible when filed
[0060] As shown in Table 2, improvement of whitening effect was
observed when the concentration of ultraphosphate is 5 to 10%.
Example 3
Variation of Whitening Effect Under Various Concentrations of
Hydrogen Peroxide
[0061] Evaluation of whitening elect under various concentrations
of hydrogen peroxide (3.5 to 10%) was performed under the following
conditions. (i) ultraphosphate: 5, 10, 20%, (ii) treatment time:
10, 20, 30 minutes, (iii) treatment temperature: 45.degree. C.,
(iv) pH 7.0. Further as controls, evaluation of individual
whitening effects of hydrogen peroxide under alkaline condition (pH
9.5 to 11.6) and ultraphosphate were also performed as comparison
groups, and the results are shown in Table 3.
TABLE-US-00003 TABLE 3 Concent- ration Residual Phos- of Tem-
Treat- ratio phate phosphate per- ment of concent- poly- polymers
ature time stain ration mers (%) pH (.degree. C.) (%) 0 -- 0 0 45
30 100% 3.5 -- 0 1 11.6 45 30 49.23% 5 -- 0 1 45 30 10 -- 0 1 10.1
45 30 20 -- 0 1 9.5 45 30 3.5 Ultra 0 -- 7.0 45 30 12.44% 3.5 Ultra
10 -- 7.0 45 30 11.42% 3.5 Ultra 20 -- 7.0 45 30 12.76% 3.5 Ultra 5
-- 7.0 45 20 17.33% 3.5 Ultra 10 -- 7.0 45 20 3.5 Ultra 20 -- 7.0
45 20 3.5 Ultra 5 -- 7.0 45 10 25.36% 3.5 Ultra 10 -- 7.0 45 10
25.10% 3.5 Ultra 20 -- 7.0 45 10 5 Ultra 5 -- 7.0 45 30 12.05% 5
Ultra 10 -- 7.0 45 30 10.46% 5 Ultra 20 -- 7.0 45 30 11.48% 5 Ultra
5 -- 7.0 45 20 14.28% 5 Ultra 10 -- 7.0 45 20 13.44% 5 Ultra 20 --
7.0 45 20 15.43% 5 Ultra 5 -- 7.0 45 10 19.63% 5 Ultra 10 -- 7.0 45
10 19.29% 5 Ultra 20 -- 7.0 45 10 19.66% 10 Ultra 5 -- 7.0 45 10
18.49% 10 Ultra 10 -- 7.0 45 10 15.83% 10 Ultra 20 -- 7.0 45 10
14.09% 0 Ultra 5 -- 6.6 45 30 0 Ultra 10 -- 6.3 45 30 56.25% 0
Ultra 20 -- 6.1 45 30 56.86% 0 Ultra 5 -- 6.6 45 20 0 Ultra 10 --
6.3 45 20 60.31% 0 Ultra 20 -- 6.1 45 20 0 Ultra 5 -- 6.6 45 10 0
Ultra 10 -- 6.3 45 10 68.42% 0 Ultra 20 -- 6.1 45 10 62.05%
indicates data missing or illegible when filed
[0062] As shown in Table 3, when only ultraphosphate was used,
every residual ratio of stain were 50% or more, and the result
indicates low whitening effect. The 30 minutes treatment of 20%
hydrogen peroxide under alkaline condition only results in 40.08%,
residual ratio of stain. In contrast, under conditions where 3.5%
hydrogen peroxide mixed with 5 to 20% ultraphosphate, or 5%
hydrogen peroxide mixed with 5 to 20% ultraphosphate, 12% or less
of residual ratio of stain is observed at pH 7.0. These conditions
indicated the highest whitening effect among all comparison groups.
In particular; compared to the comparison groups with higher
concentration of hydrogen peroxide under alkaline conditions, the
higher whitening effect was observed at lower concentration of
hydrogen peroxide at neutral pH (pH 7.0). These results indicate
that damage of tooth and gum caused by hydrogen peroxide were
minimized with ultraphosphate. Further, tooth decay is scarcely
caused because maximum whitening effect was obtained in pH range
above pH 6.5, in which tooth decay begins.
Example 4
Enhancement of Whitening Effect of Carbamide Peroxide Caused by
Ultraphosphate
[0063] About whitening effect by using carbamide peroxide, instead
of hydrogen peroxide, as a radical generator which has whitening
ability, evaluation of combination effect with ultraphosphate is
shown in Table 4.
TABLE-US-00004 TABLE 4 Improvement of whitening effect by
combinations of peroxide and ultraphosphate Concen- tration
Residual peroxide Phos- of NaOH Tem- Treat- ratio concent- phate
phosphate concent- per- ment of ration poly- polymer ration ature
time stain (%) mers (%) (N) pH (.degree. C.) (%) 0 -- 0 0 7.0 45 30
100% 15 -- 0 0 7.0 45 30 89.86% 30 -- 0 0 7.1 45 30 15 -- 0 1 11.4
45 30 27.69% 30 -- 0 1 10.9 45 30 19.01% 15 Ultra 5 0 7.0 45 30
19.45% 15 Ultra 10 0 7.0 45 30 18.04% 15 Ultra 20 0 7.4 45 30
18.71% 30 Ultra 5 0 7.0 45 30 30 Ultra 10 0 7.4 45 30 30 Ultra 20 0
6.8 45 30 12.59% 15 -- 0 0 7.0 45 60 87.73% 30 -- 0 0 7.1 45 60
60.96% 15 -- 0 1 11.4 45 60 30.39% 30 -- 0 1 10.9 45 60 20.22% 15
Ultra 5 0 7.0 45 60 14.69% 15 Ultra 10 0 7.0 45 60 13.82% 15 Ultra
20 0 7.4 45 60 15.25% 30 Ultra 5 0 7.0 45 60 10.01% 30 Ultra 10 0
7.4 45 60 30 Ultra 20 0 6.8 45 60 10.25% indicates data missing or
illegible when filed
[0064] When using carbamide peroxide only, the highest whitening
effect is 19.01% (30% of carbamide peroxide, treatment time 60
minutes) under alkaline condition. In contrast, when the treatment,
using 15% carbamide peroxide for 30 minutes, was performed under
the combination condition with sodium ultraphosphate, residual
ratio of stain is 18 to 19%. Further, the lowest residual ratio of
stain was 10.01% (in the presence of 5% of ultraphosphate) when 30%
carbamide peroxide was used for 60 minutes. These results mean that
coexistence of carbamide peroxide and ultraphosphate also brings
about high whitening effect.
Example 5
Temperature Dependence of Whitening Effect
[0065] Whitening effect at 37, 42 and 45.degree. C. was compared to
evaluate the temperature dependence of whitening effect, and the
results are shown in Table 5.
TABLE-US-00005 TABLE 5 Effect of temperature on enhancement of
whitening effect of ultraphosphate Concen- Treat- tration ment
Residual Phos- of NaOH tem- Treat- ratio phate phosphate concent-
per- ment of concent- poly- polymers ration ature time stain ration
mers (%) (N) pH (.degree. C.) (Min.) (%) 3.5 Ultra 5 0 7.5 37 10
69.61 3.5 Ultra 5 0 7.5 42 10 65.82 3.5 Ultra 5 0 7.5 45 10 25.36
3.5 Ultra 10 0 7.5 37 10 69.91 3.5 Ultra 10 0 7.5 42 10 68.12 3.5
Ultra 10 0 7 45 10 25.10 5 Ultra 5 0 7.5 37 10 53.41 5 Ultra 5 0 7
45 10 19.63 5 Ultra 10 0 7.5 37 10 57.34 5 Ultra 10 0 7 45 10 19.20
indicates data missing or illegible when filed
[0066] Table 5 suggested that, when the concentration of hydrogen
peroxide is 3.5%, higher temperature brings higher enhancement of
whitening effect under both concentration conditions of
ultraphosphate (5% and 10%), and the effect was dramatically
enhanced at 45.degree. C. Further when the concentration of
hydrogen peroxide is 5%, higher effect was obtained at 45.degree.
C. than the effect at 37.degree. C. These results suggest that the
oral composition of the present invention is preferably used at
42.degree. C. or higher.
Example 6
Effect of Polyethylene Glycol on Whitening (1), Comparison of
Whitening Effect Among Polyethylene Glycol Having Different
Molecular Weight
[0067] Whitening effect is evaluated under conditions where various
polyethylene glycols, which have different molecular weight (200,
1000, 4000, 6000 and 20000), were added to a mixture of hydrogen
peroxide and ultraphosphate so as to have a final concentration of
1%. Other conditions are as follows. (i) ultraphosphate: 10%, (ii)
hydrogen peroxide: 0 or 5%, (iii) treatment time: 10 minutes, (iv)
treatment temperature: 45.degree. C., and (v) pH 7.0. Further,
evaluations of whitening effect of ultraphosphate alone and
whitening effect under the condition where ultraphosphate was
combined only with hydrogen peroxide were also performed as
comparison groups, and the results are shown in Table 6.
TABLE-US-00006 TABLE 6 Comparison of enhancement of whitening
effect when various polyethylene glycols (PEG), which have
different weight, were added to a mixture of hydrogen peroxide and
ultraphosphate Treat- Ultra- Molec- ment Residual phosphate PEG
ular tem- ratio concent- concent- concent- weight per- Treat- of
ration ration ration of ature ment stain (%) (%) (%) PEG pH
(.degree. C.) time (%) 0 10 0 -- 7 45 10 93.50 0 10 1 200 7 45 10
92.51 0 10 1 1000 7 45 10 85.96 0 10 1 4000 7 45 10 68.93 0 10 1
6000 7 45 10 68.16 5 10 0 -- 7 45 10 24.19 5 10 1 200 7 45 10 23.94
5 10 1 1000 7 45 10 21.45 5 10 1 4000 7 45 10 19.04 5 10 1 6000 7
45 10 18.59 indicates data missing or illegible when filed
[0068] As shown in Table 6, when ultraphosphate was only contained
or when polyethylene glycol was added to the ultraphosphate, every
residual ratio of stain was 50% or higher, namely these results
indicated low whitening effect. On the other hand, when
ultraphosphate, hydrogen peroxide and polyethylene glycol were
mixed, every residual ratio of stain was less than 25%, namely,
about four times higher whitening effect than the case in the
absence of hydrogen peroxide was observed. Further, regardless of
the presence of hydrogen peroxide, when ultraphosphate and
polyethylene glycol were used together, there was a tendency that
residual ratio of stain become lower according to the increase of
molecular weight of polyethylene glycol. From these results, the
highest whitening effect was obtained when 10% ultraphosphate, 1%
polyethylene glycol which has the molecular weight of 6000 and 5%
hydrogen peroxide were combined, under neutral pH condition at
45.degree. C.
Example 7
Effect of Polyethylene Glycol on Whitening (2), Comparison of
Whitening Effect Among Polyethylene Glycol Having Different
Molecular Weights and Concentrations
[0069] Whitening effect is evaluated under conditions where various
polyethylene glycols (the molecular weight of 6000), which have
different concentrations (0 to 15%), were added to a mixture of
hydrogen peroxide and ultraphosphate, and the result is shown in
Table 7. Other conditions are as follows. (i) ultraphosphate: 10%,
(ii) hydrogen peroxide: 5%, (iii) treatment time: 10 minutes, (iv)
treatment temperature: 42.degree. C., and (v) pH 7.0. Further,
under the same conditions, comparison of whitening effect, when
various polyethylene glycol, which have different molecular
weights, were added so as to have different concentrations (0 to
1%), is shown in Table 8.
TABLE-US-00007 TABLE 7 Comparison of enhancement of whitening
effect when concentrations of polyethylene glycol having a
molecular weight of 6000 was varied Treat- Ultra- Molec- ment
Residual phosphate PEG ular tem- ratio concent- concent- concent-
weight per- Treat- of ration ration ration of ature ment stain (%)
(%) (%) PEG pH (.degree. C.) time (%) 5 10 0 -- 7 42 10 32.69 5 10
1 6000 7 42 10 27.96 5 10 3 6000 7 42 10 28.86 5 10 5 6000 7 42 10
28.63 5 10 10 6000 7 42 10 32.29 5 10 15 6000 7 42 10 28.59
indicates data missing or illegible when filed
TABLE-US-00008 TABLE 8 Comparison of enhancement of whitening
effect when concentrations and molecular weights of polyethylene
glycol (PEG) were varied Treat- Ultra- Molec- ment Residual
phosphate PEG ular tem- ratio concent- concent- concent- weight
per- Treat- of ration ration ration of ature ment stain (%) (%) (%)
PEG pH (.degree. C.) time (%) 5 10 0 -- 7 42 10 30.21 5 10 0.25
4000 7 42 10 29.59 5 10 0.5 4000 7 42 10 30.02 5 10 1 4000 7 42 10
29.43 5 10 0.25 6000 7 42 10 31.13 5 10 0.5 6000 7 42 10 25.85 5 10
1 6000 7 42 10 25.47 5 10 0.25 20000 7 42 10 26.98 5 10 0.5 20000 7
42 10 25.71 5 10 1 20000 7 42 10 25.27 indicates data missing or
illegible when filed
[0070] As shown in Table 7, under neutral pH condition at
42.degree. C., residual ratio of stain was 30% or higher when only
10% ultraphosphate and 5% hydrogen peroxide were mixed, and there
is a tendency that residual ratio of stain slightly become lower
when polyethylene glycol (molecular weight 6000) was further added
thereto in range between 1 to 15%. However, no concentration
dependence of whitening effect was observed in these cases.
[0071] As shown in Table 8, whitening effect was compared under
conditions where 1% or less polyethylene glycol was added. Under
the condition in the presence of polyethylene glycols having
molecular weight of 6000 or 20000 exist, concentration dependence
of whitening effect was observed because residual ratio of stain
became lower according to increase of concentration. However, when
the polyethylene glycol has molecular weight of 4000, similar
residual ratio of stain (about 30%), to the ratio in the condition
where polyethylene glycol was not added, was observed in every
concentration condition, namely no concentration dependence of
whitening effect was observed.
[0072] As shown in Tables 7 and 8, 0.25 to 1% of polyethylene
glycol is enough to enhance whitening elect, and adding more than
1% of polyethylene glycol has no effect on whitening. From these
results, it is revealed that noticeable enhancement of whitening
effect is observed under neutral pH condition at 42.degree. C.,
when the polyethylene glycol having 6000 or more of the molecular
weight is added so as to have a concentration of 0.25 to 1%
Example 8
Optimization of Mixing Condition of Ultraphosphate, Hydrogen
Peroxide and Polyethylene Glycol
[0073] Whitening effect is evaluated under conditions where
polyethylene glycol, which has the molecular weight of 6000, was
added to a mixture of hydrogen peroxide and ultraphosphate so as to
have a final concentration of 1%, and the result is shown in Table
9. Other conditions are as follows. (i) ultraphosphate: 0 to 20%,
(ii) hydrogen peroxide: 5%, (iii) treatment time: 10 minutes, (iv)
treatment temperature: 42.degree. C., and (v) pH 7.0. Further,
under the same condition, the evaluation of whitening effect was
performed under conditions where each polyethylene glycol was
added, which has different molecular weight, so as to have a final
concentration of 1%, and the concentration of ultraphosphate was
fixed at 0%. The result is shown in Table 10.
TABLE-US-00009 TABLE 9 Comparison of enhancement of whitening
effect in a mixture of hydrogen peroxide. ultraphosphate and PEG
when ultraphosphate concentrations were varied Treat- Ultra- Molec-
ment Residual phosphate PEG ular tem- ratio concent- concent-
concent- weight per- Treat- of ration ration ration of ature ment
stain (%) (%) (%) PEG pH (.degree. C.) time (%) 5 0 1 6000 7 42 10
97.61 5 5 1 6000 7 42 10 23.76 5 10 1 6000 7 42 10 22.47 5 20 1
6000 7 42 10 23.19 indicates data missing or illegible when
filed
TABLE-US-00010 TABLE 10 Comparison of enhancement of whitening
effect in a mixture of hydrogen peroxide. ultraphosphate and PEG
when molecular weight of PEG was varied Treat- Ultra- Molec- ment
Residual phosphate PEG ular tem- ratio concent- concent- concent-
weight per- Treat- of ration ration ration of ature ment stain (%)
(% ) (%) PEG pH (.degree. C.) time (%) 5 10 0 7 42 10 24.32 5 10 1
200 7 42 10 23.77 5 10 1 1000 7 42 10 22.69 5 10 1 4000 7 42 10
22.86 5 10 1 6000 7 42 10 21.78 5 10 1 20000 7 42 10 24.24
indicates data missing or illegible when filed
[0074] As shown in Table 9, from the comparison of whitening effect
when polyethylene glycol which has the molecular weight of 6000 was
added at 1% and the concentration of ultraphosphate was varied from
0 to 20%, it is revealed that every residual ratio of stain under
conditions, where ultraphosphate has the concentrations of 5% or
more, is 25% or less, and the residual ratios of stain became
lowest when the concentration of ultraphosphate is 10%. On the
basis of these results, whitening effect was compared, under
conditions where each polyethylene glycol was added, which has
different molecular weight, so as to have a concentration of 1%,
and the concentration of ultraphosphate was fixed at 10%. From the
result of the comparison, it was revealed that enhancement of
whitening became more effective in accordance with increase of
molecular weight, and the effect was maximized when molecular
weight is 6000, as shown in Table 10. From these results, it was
revealed that when the treatment temperature was 42.degree. C.,
addition of polyethylene glycol having the molecular weight of 6000
to a mixture of 5% of hydrogen peroxide and 10% of ultraphosphate
so as to have a concentration of 1% brings noticeable high
enhancement of whitening effect.
Example 9
Whitening Test Using Detached Teeth (1): 3.5% H.sub.2O.sub.2
[0075] In order to prepare stain deposited teeth, detached teeth
were decolorized by 30% hydrogen peroxide solution for 12 hours or
more, and the teeth were soaked in (i) protein solution (for an
hour or more), (ii) stain liquid (for 12 hours or more) and (iii)
artificial saliva (for an hour or more), in this order. As a
protein solution, SPC-5000 (collagen peptide, manufactured by Nitta
Gelatin Inc.) was used, and it is dissolved so as to have a
concentration of 1 w/v %. To make stain liquid, 5 g of instant
coffee, two lipton tea bags and two tea bags of Oi Ocha (registered
trademark) were added to 110 mL of distilled water, and the mixture
is heated in a microwave oven for about 2 minutes. Then the mixture
was cooled down in room temperature, and filtered. The artificial
saliva, which is used in this test, had a composition comprising 20
mM HEPES-KOH pH 7.0, 1.5 mM CaCl.sub.2 and 0.9 mM KH.sub.2PO.sub.4.
Whitening effect was tested by using the detached teeth stained by
the method mentioned above. The following cases were tested,
namely, one case that the stained detached tooth was treated with
hydrogen peroxide (pH 10) having different concentration (Control
Experiment) and the other case that stained detached tooth was
treated with hydrogen peroxide and 10% ultraphosphate (pH 7)
(Example 1). Then the teeth were incubated at 42.degree. C. for a
maximum of 30 minutes.
[0076] FIGS. 1A and 1B show photographs of a tooth, which was
treated with 3.5% H.sub.2O.sub.2 alkaline condition (pH 10) at
42.degree. C. for each period of time (Control Experiment). FIGS.
2A and 2B show photographs of a tooth, which was treated with 3.5%
H.sub.2O.sub.2, and 10% ultraphosphate (pH 7) at 42.degree. C. for
each period of time (Example 1). From comparison between these
figures, it is suggested that the combination of 10% ultraphosphate
and hydrogen peroxide solution under neutral pH condition brings
higher whitening effect than the case of using hydrogen peroxide
solution under alkaline condition.
Example 10
Whitening Test Using Detached Teeth (2): 5% H.sub.2O.sub.2
[0077] The following cases were tested, namely, one case that the
stained detached tooth was treated with 5% hydrogen peroxide (pH
10) and the other case that stained detached tooth was treated with
5% hydrogen peroxide and 10% ultraphosphate (pH 17). Then the teeth
were incubated at 42.degree. C. for a maximum of 30 minutes.
[0078] FIG. 3 shows photographs of a tooth, which was treated with
5% H.sub.2O.sub.2 (pH 10) at 42.degree. C. for each period of time.
FIG. 4 shows photographs of a tooth, which was treated with 5%
H.sub.2O.sub.2 and 10% ultraphosphate (pH 7) at 42.degree. C. for
each period of time.
[0079] As shown in FIGS. 3 and 4, when whitening test was performed
by using 5% hydrogen peroxide, the combination of ultraphosphate
and 5% hydrogen peroxide brings higher effect than the case of
using 5% hydrogen peroxide alone.
Example 11
Whitening Test Using Detached Teeth (3): 10% H.sub.2O.sub.2
[0080] One half of the same detached tooth surface was coated with
gel containing 10% H.sub.2O.sub.2 (pH 10), and the other half of
the tooth surface was coated with gel containing 10% H.sub.2O.sub.2
(pH 10) with 10% ultraphosphate and prepared so as to have pH 7,
and the tooth was incubated at 42.degree. C. for a maximum of 30
minutes. Carboxyvinyl polymer was added to each treatment solution
so as to have a final concentration of 0.7% as a thickening
agent.
[0081] FIG. 5 shows whitening effect on the same detached teeth
which was coated with 10% H.sub.2O.sub.2, under alkaline condition
and polymers including 10% H.sub.2O.sub.2 with 10% ultraphosphate
under neutral pH condition. As demonstrated on the same tooth in
FIG. 5, the case of the polymers including 10% H.sub.2O.sub.2 and
10% ultraphosphate under neutral pH condition (the left side) gave
higher whitening effect than the case of 10% H.sub.2O.sub.2 (the
right side).
Example 12
Whitening Test (4) Using Detached Teeth: 20% H.sub.2O.sub.2
[0082] The following cases were tested, namely, one case that the
stained detached tooth was treated with 20% hydrogen peroxide (pH
10) and the other case that stained detached tooth was treated with
20% hydrogen peroxide and 10% ultraphosphate (pH 7). Then the teeth
were incubated at 42.degree. C. for a maximum of 30 minutes.
[0083] FIGS. 6A and 6B show photographs of teeth, which were
treated with 20% H.sub.2O.sub.2 (pH 10) at 42.degree. C. for each
period of time. FIGS. 7A and 7B show photographs of teeth, which
were treated with 20% H.sub.2O.sub.2 and 10% ultraphosphate (pH 7)
at 42.degree. C. for each period of time.
[0084] As shown in these figures, when whitening is performed by
using 20% hydrogen peroxide, the combination of ultraphosphate and
20% hydrogen peroxide brings lower whitening effect than the case
using 20% hydrogen peroxide alone. Namely, when the concentration
of hydrogen peroxide is 20% or lower, the oral composition of the
present invention seems to be effective. Using 20% hydrogen
peroxide alone causes great damage to teeth and gums. On the other
hand, the combination of ultraphosphate and 20% hydrogen peroxide
gave weaker stimulus than 20% hydrogen peroxide alone.
Example 13
Effect of Infrared Light on Whitening Effect
[0085] The oral compositions of above-mentioned examples were
applied to teeth, and the applied areas were irradiated by a laser
diode for 30 seconds to 5 minutes. Ezlase (registered trademark)
manufactured by Waterlase Japan was used as the laser diode. The
output wavelength and output intensity of this laser diode were 940
nm and 7 W respectively. As a result, only about one minute
irradiation by the laser diode can dramatically enhance whitening
effect of tooth. It would appear that whitening effect by peroxide
is dramatically enhanced by the energy of the laser diode. Further,
the oral composition, to which 1 to 10% by weight of charcoal was
added, was applied to teeth, and irradiation was performed in the
same way. Then higher whitening effect was confirmed.
INDUSTRIAL APPLICABILITY
[0086] The present invention can be utilized in the industry
relating to an oral composition.
* * * * *