Note: Descriptions are shown in the official language in which they were submitted.
P7236S01 ~ ~ 3 2 ~ 2 ~
IMPROVED DENTURE AD~IBSIVE
BACKGROUND OF THE INVENTION
1. Field of the lnvention
This invention relates to denture adhesives or
stabili2ers, and particularly to an improved anhydrous
denture adhesive composition.
2. Description of the Prior Art
Traditionally, adherent powders used to secure dentures
within the mouth were prepared from such materials as finely
powdered natural gums, i.e. karaya, acacia or tragacanth
gum. These materials have the particular property of
swelling to many times their original volume upon the
addition of water to form a gelatinous or mucilaginous mass.
Denture adhesive powders may be a combinativn of one or more
natural gums, generally flavored with pleasant tasting
volatile oils. Many other additives may also be included,
such as antiseptics, stabiliz~rs, bacteriocides, special
deodorants, plasticizing agents, fillers, coloring agents,
and the like.
Cream ~orms of the denture adherent, prepared from
finely ground particies of the natural gums dispersed in a
cream base, are also available and may be used instead of
the powder compositions. In any event, when wet with water,
the natural gum in either the cream or powder formulation
expands to become a viscous gel which acts as a cushion and
an adherent between the denture plate and the gum tissue.
While these relatively simple formulations are
effective in securing dentures within the oral cavity for a
short period of time, generally more than one application of
adhesive per day i5 necessary. This is, at best,
inconvenient and therefore, most undesirable.
In recent years, there have heen numerous improvements
in the above-described simple denture adhesive formulations.
For example, V.S. Patent No. 3,736,274 discloses z denture
adhesive containing three essential ingredients: a maleic
anhydride and/or acid copolymer (with a lower alkyl vinyl
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P7236Sol 2~3282~
ether), a polymeric N-vinyl lactam, and sodium
carboxymethylcellulose, preferably incorporated into a
diluent such as petrolatum and/or mineral oil.
U.S. Patent No. 4,280,936 discloses a denture adhesive
comprising sodium carboxymethylcellulose and poly (ethylene
oxide) homopolymer in a mineral oil base.
U.S. Patent No. 4,514,528 is directed to a hydrophilic
denture adhesive which consists of an admixture of mixed,
partial salts of lower alkyl vinyl ether-maleic anhydride-
type copolymers with either sodium carboxymethylcellulose or
poly (ethylene oxide) homopolymer or both in a hydrophilic
vehicle.
U.S. Patent No. 4,518,721 discloses a denture adhesive
which consists of sodium carboxymethylcellulose and poly
~ethylene oxide) in a hydrophilic vehicle comprising certain
polyethylene glycols and, optionally, glycerin.
U.S. Patent No. 4,569,955 discloses a denture adhesive
containing an adhesive polymeric fraction comprising an
admixture of mixed, partial salts of lower alkyl vinyl
ether-maleic anhydride-type copolymers with sodium
carboxymethylcellulose in a mineral oil vehicle thickened
with polyethylene having a molecular weight of 1,000 to
21,000-
While all of the above denture adhesives provide someimprovement over simple formulations containing only finely
powdered natural gums, it is generally recognized that no
one product has yet been developed which can accommodate
over a long period of time, the many variations in
temperatures, pH and mechanical agitation which are quite
normal in the oral cavity.
It has now been found that the denture adhesive of this
invention will provide superior adhesive duration and
hslding properties over prolonged periods of time and under
unusually varied conditions, without the disadvantages
characteristic of previously known products.
P7236SOl 203282~
SUMMARY OF THE INVENTION
The novel denture stabilizers formed according to the
present invention are generally prepared by mixing a denture
adhesive base composition with additional materials to
produce denture adhesive compositions which, whether
formulated in powder or paste form, exhibit excellent
properties as denture stabilizers.
Applicant has unexpectedly discovered a denture
adhesive base composition comprising a substantially
anhydrous mixture of a cationic derivative of guar gum, a
mixed Na/Ca salt of methyl vinyl ether-maleic anhydride and
sodium carboxymethylcellulose.
In one preferred embodiment of the invention, it has
been unexpectedly discovered to form a denture adhesive
composition which comprises a substantially anhydrous
mixture of from about 40 to about 60 percent by weight,
based on the total weight of the denture adhesive
composition, of a denture adhesive base composition
containing a cationic derivative of guar gum, a mixed Na/Ca
salt of methyl vinyl ether-maleic anhydride and sodium
carboxymethylcellulose.
In another preferred embodiment, it has been
unexpectedly discovered to form a denture adhesive
composition comprising a substantially anhydrous mixture of:
a) from about 40 to about 60 percent by weight,
based on the total weight of the denture adhesive
composition, of a denture adhesive base composition
containing a cationic derivative of guar gum, a mixed Na/Ca
salt of methyl vinyl ether-maleic anhydride and sodium
carboxymethyl-cellulose; and
b) from about 40 to about 60 percent by weight,
based on the tokal weight of the denture adhesive
composition, of additional materials selected from the
group consisting of waxes, oils, preservatives,
flavoring agents, colorants, sweetening agents,
viscosity modifiers and mixtures ~hereof.
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P7236S01 2~2~24
In an especially preferred smbodiment it has been
unexpectedly discovered to form a denture adhesive
composition comprising a substantially anhydrous mixture of:
a) ~rom about 10.0 to about 20 percent by
weight, based on the total weight of the denture
adhesive composition, of a cationic derivative of guar
gum;
b) from about 20 to about 30 percent by weight,
based on the total weight of the denture adhesive
composition, of a mixed Na/Ca salt of methyl vinyl
ether-maleic anhydride;
c) from about 10 to about 25 percent by weight,
hased on the total weight of the denture adhesive
composition, of sodium carboxymethylcellulose; and
d) additional materials in an amount sufficient
to yield a denture adhesive composition having a total
weight equal to 100 percent by weight o~ the total
denture adhesive composition.
The invention also involves a method for preparing
these novel denture stabilizers.
In one pre~erred embodiment, a method ~or preparing a
denture adhesive base composition comprises: ~
a) preparing a substantially anhydrous mixture of
a cationic derivative of guar gum, a mixed Na/Ca salt
of methyl vinyl ether-maleic anhydride and sodium
carboxymethylcellulose;
b) forming a denture adhesive base composition
including said mixture; and
c3 recovering said denture adhesive base
composition.
DESCRIPTION OF THE ~
Applicant has unexpectedly discovered a novel denture
adhesive base composition comprising a substantially
anhydrous mixture of a cationic derivative o~ yuar gum, a
mixed Na/Ca salt of methyl vinyl ether-maleic anhydride and
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P7236S01 2~3~,~2~
sodium carboxymethylcellulose.
Denture adhesive compositions formed with the above-
described denture adhesive base composition yield a product
which provides surprising good performance as a denture
stabilizer~ Specifically, denture adhesives of the present
invention require fewer applications per day, exhibit
increased holding power, denture cushioning and duration of
holding, exhibit reduced oozing properties, and provide
greater consumer confidence of product function.
The invention comprises a unique combination of three
essential components, namely a cationic derivative of g~ar
gum, a mixed Na/Ca salt of methyl vinyl ether-maleic
anhydride and sodium carboxymethylcellulose. In the absence
of any o~ ~hese components ~rom the formulations of this
invention, compositions may be prepared which do not exhibit
the enhanced effect achleved from this combination.
Guar gum i~ a commercially available water-soluble
plant mucilage obtained from the ground endosperms of
Cyanopsis tetragonoloba, cultivated in Pakistan as livestock
feed.
The presently~disclosed adhesive compositions utilize a
commercially available cationic derivative of guar ~um which
has been unexpectedly found to react with sodium
carboxymsthylcellulose in the presence of the mixed Na/Ca
salt of methyl vinyl ether-maleic anhydride, to form a
denture adhesive composition exhibiting enhanced
adhesiveness, and particularly enhanced cohesive properties.
A preferred cationic derivative of guar gum which has
been found to be useful in preparing the adhesive
formulations of the invention is guar gum, 2-hydroxy-~-
~trimethyl ammonio)-propyl ether, chloride.
The mixed Na/Ca salt of methyl vinyl ether-maleic
anhydride is a commercially available material known in the
art. The mixed Na/Ca salt of methyl vinyl ether-maleic
anhydride is a hydrophilic long chain polymer which has
adhesive properties.
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P7~36S01 2~2~2~
Upon addition of the third essential component of the
invention, sodium carboxym~thylcellulose, a denture adhesive
is provided, which, upon hydration, forms an adhesive yet
extremely cohesive matrix.
Sodium carboxymethylcellulose is a commercially
available synthetic gum derived from cellulose, and
generally comprises an anionic, water-soluble, long chain
polymex. The particle size of the sodium
carboxymethylcellulose utilized in the present invention is
pre~erably 60 mesh or smaller.
When these three components are intermixed, a denture
adhesive base composition is formed which exhibits superior
characteristics as a denture stahilizer when incorporated
into a denture adhesive composition. Specifically, denture
adhesive compositions formulated with the denture adhesive
base composition of the invention exhibit improved denture
holding and improved denture adhesive duration properties.
The denture adhesive base composition may comprise from
about 12.5 to about 50 percent by weight of a cationic
derivative of guar gum, from about 33 to about 75 percent by
weight of a mixed Na/Ca salt of methyl vinyl ether-maleic
anhydride, and from about 12.5 to about 62 percent by weight
o~ s~dium carboxymethylcellulose, based on the total weight
of the denture adhesive base composition.
Preferably, the denture adhesive base composition
comprises from about 17 to about 27 percent by weight of a
cationic derivative of guar gum, from about 43 to about 53
percent by weight of a mixed Na/Ca salt of methyl vinyl
ether-maleic anhydride, and from about 17 to about 27
percent by weight of sodium carboxymethylcellulose, based on
the total weight of the denture adhesive base composition.
~ he denture adhesive base compositions are useful to
prepare denture adhesive compositions. According to the
invention, a denture adhesive composition is provided which
comprises a substantially anhydrous mixture of from about 40
to about 60 percent by weight, based on the total weight of
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P7236S01 2 ~3 2~ ~ ~
the denture adhesive composition wherein the denture
adhesive base composition contains three essential
components, a) a cationic derivative of guar gum, b) mixed
Na/Ca salt of methyl vinyl ether-maleic anhydride and c)
sodium carboxymethylcellulose.
In addition to the foregoing materials, the denture
adhesive composition may be formulated with additional
components well known in the denture adhesive art. Such
additional materials utilized in the invention may comprise
waxes, oils, preservatives, flavoring agents, colorants,
sweetening agents, viscosity modifiers and so forth.
The waxes useful in the invention comprise both natural
and synthetic waxes and include without limitation animal
waxes such as beeswax, lanolin and shellac wax, vegetable
waxes such as carnauba, candelilla and bayberry wax, mineral
wax such as petroleum waxes including paraffin, and
microcrystalline.
The oils useful in the invention include without
limitation mineral oil, vegetable oil such as corn, soybean,
cottonsaed, castor, palm and coconut oils and animal oil
such as fish oil, and oleic acid.
Flavoring agents well known to the denture adhesive art
may be added to the compositions of the instant invention.
These flavoring agents may be chosen from synthetic flavor
oils and/or oils derived from plants, leaves, flowers,
fruits and so forth, and combinations thereof.
Representative flavor oils include: spearmint Dil, cinnamon
oil, oil of wintergreen (methylsalicylate) and peppermint
oils. Also useful are artificial, natural or synthetic
fruit flavors such as citrus oil including lemon, orange,
grape, lime and grapefruit, and fruit essences including
apple, strawberry, cherry, pineapple and so forth. The
flavoring agent may be a liquid, spray dried, encapsulated,
sorbed on a carrier and mixtures thereof. A preferred
flavoring agent is peppermint oil, commercially available
from Rose Mitcham. The amount of flavoring agent utilized
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P7236S01 2~3282~
may vary depending on such factors as flavor ~ype, adhesive
formulation and strength desired. In general, amounts of
about 0.01% to about 5.0% by weight of the total denture
adhesive composition are usable, with amoun~s of about 0.05%
to 0.15% being preferred.
Preservatives which may be used in the denture adhesive
formulations of the invention include those known
antimicrobial agents conventionally employed in the art,
such as benzoic acid and sodium benzoate; the parabens;
sorbic acid and sorbates; propionic acid and propionates;
acetic acid and acetates; nitrates and nitrites; sulfur
dioxide and sulfites; antibiotics; diethyl pyrocarbonate;
epoxides; hydrogen peroxide; and phosphates. The parabens
include the methyl, ethyl, propyl, and butyl esters of para-
hydroxybenzoic acid. Methyl paraben and propyl paraben are
the preferred preservatives of the invention, preferably
utilized in amounts of about 0O03% to about 0.6% by weight
of the total denture adhesive composition.
The denture adhesive compositions may also include the
use of sweeteners well known in the art.
T~e sweetening agent may be selected from a wide range
of materials including wat~r-soluble agents, water-soluble
artificial sweeteners; and dipeptide based sweeteners,
including mixtures thereof. Without being limited to
particular sweeteners, representative illustrations
encompass:
A. Water-soluble sweetening agents such as
monosaccharides, disaccharides and polysaccharides such as
xylose, ribose, glucose, mannose, galactose, fructose,
dextrose, sucrose, sugar, maltose, partially hydrolyzed
starch, or corn syrup solids and sugar alcohols such as
sorbitol, xylitol, mannitol, maltitol, hydrogenated starch
hydrolysate and mixtures thereof.
B. Water-soluble artificial sweeteners such as the
soluble saccharin salts, i.e., sodium or calcium saccharin
salts, cyclamate salts, acesulfame-K, sucralose and the
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P7236S01 2~32~2~
like, and the free acid form of saccharin.
C. Dipeptide based sweeteners such as L-aspartyl-L-
phenylalanine methyl ester and materials described in U.S.
Patent No. 3,491l131, L-D~aspartyl-N-(2,2,4,4-tetramethyl-3-
thietanyl-D-alaninamide hydrate) and the like.
In general, the amount of sweetener will vary with the
desired amount of sweetener selected for a particular
denture adhesive formulation. This amount may be about
0.001% to about 5% by weight of the final denture adhesive
composition when using an easily extractable sweetener.
ThP colorants useful in the present invention include
pigments such as titanium dioxide, and may also include dyes
suitable for food, drug and cosmetic applications. These
colorants are known as F.D. & C. dyes. The materials
acceptable for the foregoing spectrum of use are preferably
water-soluble. Illustrative examples include indigo dye,
known as F.D. & C. Blue No. 2, which is the disodium salt of
5,5'-indigotindi-sulfonic acid. Similarly, the dye known as
F.D. & C. Green No. l, comprises a triphenylmethane dye and
is the monosodium salt of the 4-[4-N-ethyl-p-
sulfobenzylamino) diphenylmethylene]~ N-ethyl-N-P-sulfo-
benzyl)-2, 5-cyclohexadienimine]. A prsferred colorant is
F.D. ~ C. Red No. 3. A ~ull recitation of F. D. & C. and DA
& C. colorants and their corresponding chemical structures
may be found in the Kirk-Othmer Encyclopedia of Chemical
Technology, 3rd Edition, in Volume 6, at pages 561-595.
The ~iscosity modifiers useful herein include
polyethylene and its derivatives, quaternary ammonium
compounds and similar agents, starches, gums and casein
gelatin. In general, the viscosity of the present adhesive
formulations should be modified such that the final product
may be readily extruded. Extrusion characteristics of the
present denture adhesives have been determined to be most
ideal when the compositions contain less than 60 percent
total solids.
Another optional additive useful in the adhesive
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P7236S01 2~2~2~
formulations of the present invention is ethylene oxide
polymer. Ethylene oxide polymer is a water-soluble, non-
ionic white powder having an averaye molecular weight of
about 100,000 to about 5,000,000. The preferred ethylene
oxide polymer optionally utilized in the present invention
is commercially available.
Fumed silica is an additional optional additive which
may be included in the inventive denture adhesive
formulations. Fumed silica is a commercially available
colloidal form of silica made by the combustion of silicon
tetrachloride.
In another aspect of the invention, a denture adhesive
composition is provided which comprises a substantially
anhydrous mixture of:
a) from about 40 to about 60 percent by weight,
based on the total weight of the denture adhesive
composition, of a d~nture adhesive base composition
containing a cationic derivative of guar gum, a mixed
Na/Ca salt of methyl vinyl ether-maleic anhydride and
sodium carboxymethylcellulose; and
bJ from about 40 to about 60 percent by weight,
based on the total weight of the denture adhesive
composition, of additional materials selected from the
group consisting of waxes, oils, preservatives,
flavoring agents, colorants, sweetening agents,
viscosity modifiers and mixtures thereof.
In an especially preferred aspect of the invention, a
denture adhesive composition is formed which comprises a
substantially anhydrous mixture of:
a) from about 10 to about 20 percent by weight,
based on the total weight of the denture adhesive
composition, of a cationic derivative of guar gum;
b) from about 20 to about 30 percent by weight,
based on the total weight of the denture adhesive
composition, of a mixed Na/Ca salt of methyl vinyl
ether-maleic anhydride;
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P7236Sol 2~3282~ -
c) from about lo to about 2~ percent by weight,
based on the total weight of the denture adhesive
composition, of sodium carboxymethyl~ellulose; and
d) additional materials i.n an amount sufficient
to yield a denture adhesive composition having a total
weight equal to 100 percent by weight oP the total
denture adhesive composition.
The denture adhesive compositions may be in the form of
a paste or powder mixture. The means for preparing such
formulations is well known in the denture adhesive art.
In a preferred aspect of the invention, the denture
adhesive base composition may further include at least one
cream base material selected from the group consisting of
petrolatum, natural and synthetic oils and mixtures thereof.
In another preferred aspect of the invention, the
denturs adhesive base composition~ may further include a
cream base material which is a combination of mineral oil
with a minor amount of polyethylene wax having an average
molecular weight of 1,000 to 20,000.~
In another preferred aspect of the invention, the
denture adhesive base composition may further include non-
toxic, powdered, excipient materials.
~ he denture adhesive compositions and denture adhesive
base compositions of this invention may be formulated to
contain the cationic derivative~of guar gum, mixed~ Na/Ca
salt of methyl vinyl ether-maleic anhydride and sodium
carboxymethylcellulose in either~powder or paste Eorm. In
the powder form, the components are admixed with the
flavoring agents and colorants, together with other non-
essential ingredients such as non-toxic anti-caking agents
(silica, magnesium stearate, talcum powder or the like).
The mixture of ingredients is thoroughly agitated or stirred
to yield a generally homogenous intermixing of all
components. In the paste formulations, the cationic
derivative of guar gum, mixed Na/Ca salt of methyl vinyl
ether-maleic anhydride and sodium carboxymethylcellulose are
P7236Sol 2~3282~
admixed with petrolatum, along with the previously described
waxes, oils, preservatives, flavoring agents, colorants,
sweetening agents, viscosity modifiers and so forth.
A particularly preferred paste or cream formulation is
prepared by utilizing as the cream or paste base, the
product of U.S. Patent No. 3,215,539, the disclosure of
which is incorporated herein by reference. The cream or
paste base of this patent is characterized as a mixture of
white petroleum oil with a minor amount of a polyethylene
wax having an average molecular weight of 1,000 to 20,000.
This product is described as having emollient properties,
useful in the formulation of medicaments where absorption of
the medicaments by the skin is of paramount importance.
Denture adhesive creams formulated with this petroleum
oil/polyethylene wax blend as the paste or cream base
display unusually good stability, extrudability and product
appearance.
The method for preparing the denture adhesive
compositions according to the present invention, whether
formulated as a powder, paste or cream employs conventional
types of mixing equipmen~ which are ]cnown in the art for
blending, heating and cooling solids and liquids.
The method for preparing the denture adhesive base
compositions and denture adhesive compositions containing
the same may be conveniently prepared by mixing the
components until a homogeneous mixture is obtained and
xecovering the resulting product. Preferably the base
composition is prepared as a preblended formulation which
can be mixed with the remaining components used to prepare
the final formulation. Mixing is conveniently performed at
temperatures suitable to melt the co~ponents to be blended.
For example, if polyethylene and mineral oil are to be
employed sush material may be heated to temperatures from
about 50 to 110C, and are preferably cooled prior to
blending with the base preblend. Flavoring agents may be
added to the preblend and/or the wax/oil mixture prior to
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P723~S01 ~032~2~
mixing in the final mixture.
Whether formulated as a powder, paste or cream, thedenture adhesive compositions and base compositions of this
invention, when applied to dentures and exposed to moisture,
hydrate to form adhesive compositions which exhibit
unexpectedly superior characteristics in comparison with
denture adhesives of the prior art. Once formulated the
compositions may be used or stored for future use.
The following examples are given to illustrate the
invention~ but are not deemed to be limiting thereof. All
percentages given throughout the specification are based on
the weight of the final denture adhesive composition unless
otherwise indicated and are based on 100% by weight.
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P7236S01 2~3282~
EXAMPLE 1
Preparation of a Denture Adhesive Cream
A denture adhesive cream was prepared from the
following ingredients:
Percent
Inqredients W/W
Mineral oil 19.00
Petrolatum 20.00
Fumed silica 1.0
Mixed Na/Ca salt of methyl
vinyl ether-maleic anhydride 28.00
Sodium carboxymethylcellulose 15.00
Cationic derivative of guar gum 15.00
Ethylene oxide polymer 1.85
Methyl paraben 0.05
Propyl paraben 0.10
100. 00
A. Weigh mineral oil and~petrolatum into a pot, and mix
to form a homogenous mixture while raising the temperature
to 90-95C. Check to assure complete solution. With
continued mixing, cool to at least 45C.
B. Add methyl paraben and propyl paraben to the mixture
from Step A and continue mixing until a homogenous ~lend i5
obtained.
C. Preblend the ca*ionic derivative of guar gum, mixed
Na/Ca salt of methyI vinyl ether-maleic anhydride, sodium
carboxymethylcellulose and ethylene oxide polymer; add to
the above mixture with continued mixing. After about 5
minutes scrape down as needed. Reduce pressure to about 28-
29 inches vacuum and mix ~or about 5-10 additional minutes.
The product is removed and stored for use.
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P7236S01 ~32~2~
The mixture prepared according to the aforementioned
procedure when hydrated provided excellent adhesive and
cohesive characteristics.
:
'
:
:
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P7236S01 2~3282~ ~
EXAMPLE 2
Preparation of a Denture Adhesive Cream
A denture adhesive cream was prepared according to the
procedure of Example 1, using the following ingredients:
Percent
Inaredients
Mineral oil 21.5
Petrolatum 22.5
Fumed silica l.OO
Mixed Na/Ca salt of methyl
vinyl ether-maleic anhydride 27.00
Sodium carboxymethylcellulose 13.00
Cationic derivative of guar gum 13.00
Ethylene oxide polymer1.85
Methyl paraben 0.05
Propyl paraben 0.10
.
The mixture of th~is~example when hydrated set up to
form a cohesive, non-oozing denture adhesive exhi.biting
excellent denture holding and adhesive duration properties.
The invention being thus described, it will be obvious
that the:same may be varied in many ways. Such variations
are not to be regarded as a departure from the spirit and
scope of the invention and all such modifications are
intended to be included within the scope of the following
claims. ~
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