U.S. patent number 3,892,843 [Application Number 05/387,678] was granted by the patent office on 1975-07-01 for prophylactic dental compositions.
Invention is credited to Howard R. Alexander, Joseph C. Muhler.
United States Patent |
3,892,843 |
Muhler , et al. |
July 1, 1975 |
Prophylactic dental compositions
Abstract
A specific particle size distribution of feldspar is employed as
both a cleaning and a polishing agent for teeth. It consists
initially of a powder that, preferably at the time of use, is mixed
with a moistener and becomes a paste to be used by the dentist or
dental hygienist. It can be combined with a humectant but in
smaller proportions than heretofore. It can be used with or without
a dental caries-reducing amount of a fluoride anticariogenic agent,
either stannous or sodium fluoride, and is more effective than
prior materials though mixed with much smaller quantities. It can
be supplied in a sectional kit wherein the initially-separated wet
and dry ingredients can be joined at the time of use. It can be
used as a self-administered prophylactic paste for mass treatment
applications.
Inventors: |
Muhler; Joseph C. (Sturgis,
MI), Alexander; Howard R. (Prescott, AZ) |
Family
ID: |
23530919 |
Appl.
No.: |
05/387,678 |
Filed: |
August 13, 1973 |
Current U.S.
Class: |
424/52; 424/676;
424/650 |
Current CPC
Class: |
A61Q
11/00 (20130101); A61K 8/26 (20130101); A61K
2800/412 (20130101) |
Current International
Class: |
A61K
8/22 (20060101); A61K 8/19 (20060101); A61Q
11/00 (20060101); A61k 009/00 () |
Field of
Search: |
;424/52 |
References Cited
[Referenced By]
U.S. Patent Documents
|
|
|
3105013 |
September 1963 |
Saul et al. |
3151027 |
September 1964 |
Cooley et al. |
3804946 |
April 1974 |
Harrison et al. |
|
Primary Examiner: Roberts; Elbert L.
Attorney, Agent or Firm: Rogers, Ezell & Eilers
Claims
What is claimed is:
1. A prophylactic dental cleaner and polisher comprising feldspar
in finely-divided state, substantially all of the particles passing
through a 20 mesh screen, and the essential particles have a size
range of about 37 microns to about 420 microns.
2. The product of claim 1, wherein the size range of feldspar
particles is approximately:
0-5% retained on a 100 mesh screen;
0-15% retained on a 200 mesh screen;
0-25% retained on a 325 mesh screen;
55-100% pass through a 325 mesh screen;
90-100% are retained on a 600 mesh screen.
3. The product of claim 1 wherein a majority of the particles pass
through a 100 mesh screen.
4. The product of claim 1 wherein the feldspar has a composition
substantially as follows:
the feldspar may be alpha quartz
5. The product of claim 4 wherein the feldspar has the
composition:
6. The product of claim 1, admixed with a binder and a humectant
from the group consisting of glycerine, mannitol, sorbitol,
propylene glycol, polyhydroxy alcohol, th humectant being in the
ratio of about 2% to at least about 20% by weight of the mix.
7. The product of claim 6, wherein the humectant is in the ratio of
about 2-8% by weight of the mix.
8. The product of claim 1, with also an anticariogenic amount of a
fluoride adjuvant taken from the group consisting of sodium
fluoride and stannous fluoride.
9. The product of claim 1, with the adjuvant stannous fluoride in
the amount of about 1-10% by weight of the amount of feldspar.
10. The product of claim 1, with the adjuvant sodium fluoride in
the amount of about 0.5% - 5.0% of the amount of feldspar.
11. A prophylactic dental paste comprising a caries-reducing amount
of fluoride-containing anticariogenic adjuvant and finely-divided
feldspar which analyzes about 65 to about 68% SiO.sub.2, from about
0 to about 15% K.sub.2 O, from about 0 to about 3% CaO, from about
5% to about 10% Na.sub.2 O, and the balance substantially aluminum
oxide, and having the following particle size distribution by
weight:
said feldspar being free of particles retained on 20 mesh.
12. The prophylactic paste of claim 11 characterized by containing
not greater than 8% by weight of a humectant.
13. The prophylactic paste of claim 11 wherein said finely-divided
feldspar is substantially free of particles retained on a 170 mesh
screen.
14. The prophylactic paste of claim 13 including at least 20% of a
humectant
15. The prophylactic paste of claim 11 wherein said
fluoride-containing adjuvant is sodium fluoride.
16. The prophylactic paste of claim 12 wherein said
fluoride-containing adjuvant is stannous fluoride.
17. A kit for preparing a dental prophylactic paste comprising a
first compartment which includes a predetermined quantity of
finely-divided feldspar analyzing from about 65-68% SiO.sub.2, less
than 15% K.sub.2 O, from 0 to about 3% CaO, from about 5 to about
10% Na.sub.2 O, the balance being substantially aluminum oxide, and
having a particle size distribution by weight such that 0 to 5% is
retained on a 100 mesh screen, 0 to 15% is retained on a 200 mesh
screen, 0 to 25% is retained on a 325 mesh screen, the remainder of
which pass through a 325 mesh screen, none of said particles being
retained on a 20 mesh screen, and a second compartment which
includes a predetermined quantity of an aqueous solution of a
fluoride-containing anticariogenic agent and which is adapted to be
combined with the contents of the first compartment to provide a
prophylactic paste containing a caries-reducing amount of said
agent.
18. The kit of claim 17 wherein said compartments together contain
not greater than 8% of a humectant.
19. A kit for preparing a dental prophylactic paste in approximate
amount for a single dental prophylaxis treatment, comprising a
source of finely-divided feldspar analyzing from about 65-68%
SiO.sub.2, less than 15% K.sub.2 O, from 0 to about 3% CaO, from
about 5 to about 10% Na.sub.2 O, the balance being substantially
aluminum oxide, and having a particle size distribution by weight
such that 0 to 5% is retained on a 100 mesh screen, 0 to 15% is
retained on a 200 mesh screen, 0 to 25% is retained on a 325 mesh
screen, the remainder of which pass through a 325 mesh screen, none
of said particles being retained on a 20 mesh screen; a source of a
fluoride-containing anticariogenic agent in aqueous solution, said
sources together containing not greater than 8% of a humectant,
feldspar measuring means for measuring out from said finely-divided
feldspar sufficient for a single dental prophylaxis treatment
therewith, and solution measuring means for measuring out of said
solution of anticariogenic agent a predetermined quantity of
finely-divided feldspar, to provide a paste containing a
caries-reducing amount of said agent.
20. A kit for preparing a dental prophylactic paste comprising a
first compartment containing finely-divided feldspar in
predetermined amount analyzing from about 65-68% SiO.sub.2, less
than 15% K.sub.2 O, from 0 to about 3% CaO, from about 5 to about
10% Na.sub.2 O, the balance being substantially aluminum oxide, and
having a particle size distribution by weight such that 0 to 5% is
retained on a 100 mesh screen, 0 to 15% is retained on a 200 mesh
screen, and to 25% is retained on a 325 mesh screen, the remainder
of which pass through a 325 mesh screen, none of said particles
being retained on a 20 mesh screen; and a second compartment which
includes an aqueous solution of a fluoride-containing
anticariogenic agent in predetermined amount adapted to be combined
with the contents of said first compartment to provide a
prophylactic paste containing a caries-reducing amount of said
agent, and means for communicating said compartments to permit the
contents thereof to combine to form said paste.
21. The kit of claim 20 wherein said compartments together contain
not greater than 8% of a humectant.
22. A therapeutic method for cleaning and polishing the teeth and
simultaneously treating them with a fluoride which comprises:
scrubbing the teeth with a paste containing finely-divided feldspar
analyzing from 65-68% SiO.sub.2, less than 15% K.sub.2 O, from 0 to
3% CaO and from 5-10% Na.sub.2 O with the balance being
substantially aluminum oxide, and a caries-reducing amount of a
fluoride-containing anticariogenic adjuvant.
23. The method of claim 22 wherein said paste contains at least 20%
of a humectant.
24. The method of claim 22 wherein the feldspar, with less than 8%
of a humectant, is mixed with the anticariogenic adjuvant at the
time of use.
25. The method of claim 24 wherein said humectant is propylene
glycol.
26. The method of claim 21 wherein the paste contains from about
0-5% of TiO.sub.2, about 0-0.50% saccharine as a sweetner, and
about 0-1.0% flavoring.
27. A material for use on teeth to reduce enamel solubility,
comprising finely divided felspar particles and an anticariogenic
enamel solubility reducing quantity of a fluoride, the felspar
being one low in calcium and magnesium ions.
28. The material of claim 27 wherein the fluoride is from about 1%
to about 10% stannous fluoride.
29. The material of claim 27 wherein the fluoride is from about 2%
to about 6% stannous fluoride.
30. The material of claim 27 wherein the fluoride is from about
0.5% to 1.0% sodium fluoride.
31. The material of claim 27 wherein substantially all of the
felspar particles pass through a 170 mesh screen.
32. The material of claim 27 with a humectant to prevent the
material from drying out and becoming hard.
33. The material of claim 32, wherein the humectant is no greater
than about 8% by weight.
34. The material of claim 32 wherein the anticariogenic fluoride
and other ingredients are separate until the time of use.
35. In a method of preparing a material for treating teeth, the
steps of: mixing a material including finely divided felspar low in
calcium and magnesium, with an anticariogenic enamel solubility
reducing amount of a fluoride, at the time of use, for use
thereupon in the mouth of a patient.
36. In a method of claim 34, the further steps of: initially
providing the dry material to include a humectant and a binder, in
a first separate compartment of a multi-compartment receptacle; and
providing liquid material comprising an aqueous solution of the
anticariogenic fluoride, in a separate compartment; and joining the
said materials from the two compartments at the time of use.
Description
FIELD OF THE INVENTION
The present invention relates to the field of dental prophylaxis,
and more particularly to prophylactic cleaning and polishing agents
wherein both sodium and stannous fluoride systems can be used.
Although food particles, mild stains from tea, tobacco, and coffee
can be removed to a large extent from teeth by regular brushing
with most commercial dentifrices, good preventive dentistry
suggests that exogenous stains, calculus (tartar) and various other
accumulated stains must be removed periodically by a dentist or
dental hygienist. For maximum results, the prophylactic paste which
is used by the dentist or hygienist should be capable of removing
the stains which are not removed by daily home use of a commercial
dentifrice. Professional dental prophylaxis should result in clean,
lustrous teeth, and the polishing agent employed by the dentist or
hygienist should accordingly be capable not only of thoroughly
cleaning the teeth, but also of polishing the teeth to a high
luster without excessive scratching.
Various dental abrasives have been employed for dental prophylactic
treatment. Levigated alumina, for example, is an excellent
polishing agent but is unduly abrasive to enamel, dentin, and
cementum. Precipitated chalk cleans teeth fairly well but produces
a rough tooth surface. Flour of pumice, a popular ingredient of
dental prophylactic pastes, is a fair cleaner but is abrasive and
produces a poor polish.
U.S. Pat. Nos. 3,257,282, 3,330,732 and 3,378,445 are referred to
as describing a number of cleaning and polishing agents relating
expecially to the improvement consisting of the use of
finely-divided zirconium silicate having a specified particle size
distribution, the larger particle sizes serving to clean and the
smaller sizes to polish the teeth. The use of zirconium silicate in
prophylactic dentistry has several drawbacks. First, particle sizes
of about 70 microns are required for good cleaning, but such sizes
cause undesirably high abrasiveness and do not polish well. To
obtain polishing it is necessary to include small sized particles,
which have little cleaning effect. This necessary addition of very
small particle sizes required for polishing limits the quantity of
large particle sizes which can be employed for needed cleaning, and
vice versa. Second, although zirconium silicate does not initially
greatly reduce the availability of ionizable fluorine from a
fluoridecontaining anticariogenic agent such as tin fluoride (U.S.
Pat. Nos. 3,257,282 and 3,378,445) such zirconium silicate-fluoride
mixtures nonetheless ordinarily contain the fluoride adjuvant in
large quantities in order to compensate for the gradual loss in
activity of this component in the mixtures. The taste of the
zirconium silicate - stannous fluoride adjuvant mixture is
nauseating, and 7- 10% of the patients gag and vomit when such
compositions are used to clean their teeth.
Zirconium silicate, as used commercially, usually combined with
several ingredients to provide a prophylactic paste, is applied to
the teeth by means of a rubber "prophy" cup which is rotated by an
engine-driven dental handpiece. During this procedure, portions of
the abrasive come into contact with the moving metallic parts in
the dental handpiece, and cause the same to wear. Further, the
glycerin-containing zirconium silicate pastes which are
commercially available tend to "sling" during the cleaning
operation; that is, due to the centrifugal force on the paste
generated by the rapidly rotating prophylactic cup, the paste tends
to fragmentize and is hurled outwardly into the mouth from the
spinning cup.
It has been found that feldspar in certain size ranges can be used
as a combined cleaning and polishing agent, overcoming the above
problems of prior art. Tests show that both good cleaning and good
polishing results are obtained from a range of particle sizes
within given limits, so that all particles participate in both
functions, regardless of size. This has been demonstrated with
particle sizes from about 40 to 325 mesh, and about 420 to about 37
M. Cleaning and polishing are obtained with less scratching of the
surface than with prior materials. Also it has been found that
larger particles of feldspar, in contrast to other abrasives, are
less abrasive than smaller particles of other materials, which
accentuates the advantage.
In addition, with feldspars the amount of anticariogenic agent
added can be sharply reduced, and yet superior reduction of enamel
solubility is obtained. Such property has, among others, the
advantage that repulsive taste is minimized or avoided. And where
there are no active caries, the feldspar can be mixed with sodium
fluoride instead of stannous fluoride, thereby eliminating the
taste problem.
In addition, the material can be supplied as a powder mix, and
mixed with liquid at the time of use. This can eliminate at least a
major part of the glycerine or other such material familiarly used
in these pastes, and thereby improves the effectiveness of the
fluoride and reduces slinging and injury to the handpiece. The
feldspar can be used with less humectant, thereby providing better
cleaning.
It is an object of the present invention to provide a new dental
prophylactic cleaner and polisher capable of both effective
cleaning and polishing of teeth with minimum enamel Scratching.
Another object is to provide a kit for the preparation of such
material into a paste. A further object proportioned to provide a
dental prophylactic paste that can be proportined to suit cleaning
of childrens' or of adults' teeth. It is another object of the
invention to provide a prophylactic paste capable of effective
cleaning and polishing of teeth, which includes either a stannous
or sodium fluoride-containing anticariogenic agent and which is
pleasing to the taste.
It is yet another object of the invention to provide a dental
prophylactic paste including a fluoride-containing anticariogenic
agent in which the quantity of fluoride can be substantially
reduced, and yet which can obtain better enamel solubility
reduction, which surprisingly is possible with certain of the
feldspars as the cleaning and polishing agent.
It is a further object of the invention to provide a method for the
effective cleaning and polishing of teeth with simultaneous
anticariogenic fluoride treatment, which treatment does not cause
gagging or emesis in patients.
It is yet a further object of the invention to provide a dental
prophylactic paste adapted for use with a prophylactic cup which
does not produce objectionable dental handpiece wear.
The Principal Feldspar Material and Size
Feldspars of various compositions are known, and are basically
potassium, sodium, calcium and barium-containing aluminum silicates
or mixtures thereof. Reference is made to Searle, A. B. &
Grimshaw, R. W., The Chemistry and Physics of Clays and Other
Ceramic Materials, Third Ed., Earnest Ernest Benn Ltd., London,
1960, pp. 167- 169, 892. The preferred feldspar employed in the
present invention as a cleaning and polishing material is a
combination of sodium aluminum silicate and potassium aluminum
silicate. The composition by weight may have approximately the
following:
Sodium as Na.sub.2 O 3 - 11% Calcium, Al, SiO.sub.2 0 - 3% as CaO
Potassium to 15% as K.sub.2 O Si 60 - 70% as SiO.sub.2 (a portion
may be alpha quartz to 5% of the feldspar) Al.sub.2 O.sub.3
Balance, or 15 - 25% Impurities 1 - 5%
While a feldspar higher in calcium may be used for cleaning and
polishing the teeth, the feldspars should be low in calcium and
magnesium ions when combined with fluoride for therapeutic
treatment, as will be explained.
A particularly useful feldspar has approximately the following
composition by weight:
Silica, SiO.sub.2 66.8% (66.8 - 68.5) Alumina, Al.sub.2 O.sub.3
19.6 (17.5 - 19.6) Iron oxide, Fe.sub.2 O.sub.3 0.04 (.04 - .08)
Calcium oxide, CaO 1.7 (0.3 - 1.7) Magnesium oxide, MgO Tr. (Tr.)
Sodium oxide, Na.sub.2 O 6.9 (3.0 - 6.9) Potassum oxide, K.sub.2 O
4.8 (4.5 - 10.4)
The parenthetical percentages are ranges of the feldspars that can
be used as such or mixed to form the material used. A nepheline
syenite may be mixed in also to increase the sodium.
This feldspar of the present invention has a particle size range
such that substantially none of the particles is retained on a 20
mesh screen and the size range is essentially between 40 and 325
mesh. Preferably, the feldspar particle size distribution is such
that by weight approximately:
0% (841 Microns) retained on a 20 mesh screen; 0-5% (149 Microns)
retained on a 100 mesh screen; 0-15% (74 Microns) retained on a 200
mesh screen; 0-25% (44 Microns) retained on a 325 mesh screen;
55-90% (44 Microns) pass through a 325 mesh screen.
The screen sizes referred to herein are of the U.S. Sieve Series,
ASTM specification E-11-61. Good cleaning and polishing without
serious scratching are pronounced when the feldspar particle size
range is such that a majority of the particles by weight pass
through a 100 mesh screen. Substantially all are retained on a 600
mesh screen.
The feldspar of the foregoing composition and size ranges can be
mixed with water and used as a prophy cleaner and polisher. It
should, however, incorporate a binder (0.1- 0.5%) and a small
amount (2- 8.0%) of humectant.
The dry ingredients may be provided to dentists and dental
hygienists in powder form, to which the professional may add water
or a fluoride-containing aqueous solution at the time of use to
form a paste conforming to the particular requirements at hand.
Within the indicated size range, the particles are effective for
both cleaning and polishing. Hence, it is unnecessary to be
meticulous in proportioning large and small particles, so as to
obtain a blend that can both clean and polish teeth. The value of
this can be further understood by recognizing that for prophylactic
cleaning and polishing of children's teeth, very little actual
scouring is required, whereas for adults' teeth, stained by
tobacco, coffee, eggs and the like, substantial scouring is
required. With prior art cleaners, separate mixes of essentially
finer sizes are made, where necessary, to avoid excess and
unnecessary scratching of the teeth, and other mixes of larger
sized particles are made to perform the difficult cleaning
adequately.
With the feldspar of the present invention, it is possible to use a
single overall size range of particles for both children's teeth or
adults'. And importantly, in both cases the scratching is less
injurious to the enamel than with the prior art materials. If
desired, the present feldspar materials may be used in smaller
sizes (such as 170- 350 mesh) for children's teeth, but tests
indicate it to be unnecessary.
This product is thus much safer to use than prior art materials,
because it cleans and polishes as well or better than prior art
materials, with less deleterious abrasion and scratching.
The Pastes
Preferably at the time of use, the powder is made into a paste,
that includes 90- 95% of the feldspar as defined above, a binder
(that acts also as a dispersing agent) which preferably is
hydroxyethyl cellulose, hydroxymethyl cellulose, or mixtures
thereof as binders, in amounts of from about 0.1 to about 0.5% by
weight, and a humectant such as propylene glycol or glycerine in an
amount of from about 2 to about 8% by weight. The binder aids in
dispersing the glycerine or other humectant. As noted later, the
paste may contain a fluoride anticariogenic agent, and may contain
small amounts of bleaching, coloring and flavoring materials as are
known in the art.
The above paste has the unusual characteristic of being resistant
to "slinging" during cleaning of the teeth with a rubber
prophylactic cup. "Slinging" refers to the tendency of a
prophylactic paste to be hurled outwardly from the rapidly spinning
prophylactic cup into the mouth, which is often times unpleasant to
patients. By reducing the slinging tendency of prophylactic paste,
patient and operator discomforture is reduced and the amount of
paste which is required for a complete treatment is also
reduced.
The material also reduces wear on the handpiece.
The Pastes: Humectant Use
Dental pastes in general ordinarily contain an abrasive agent,
water (such as an aqueous solution of a fluoride), and a humectant
such as glycerine. The purpose of the humectant is to reduce the
propensity of aqueous pastes to dry out and become hard. When
furnished in pre-packaged form to be used over a long period of
time, such as in tubes or jars or the like, the paste of the
present invention should contain at least about 25% by weight of a
humectant such as glycerine, mannitol, sorbitol, propylene glycol,
or other polyhydroxy alcohols. Glycerine and propylene glycol are
the usual humectants in tooth pastes.
The humectants, especially glycerine, have the disadvantages of
giving an oily taste in the mouth, of reducing the anticariogenic
effect of fluoride adjuvants, and of reducing the cleaning effect.
Reducing the percentage of humectant improves all of these problem
situations.
The reduction of the cleaning characteristics of the finely-divided
feldspars described above by larger quantities of humectant is
believed to occur because the feldspar particles, as small,
sharp-edged platelets, slide across the tooth surface during
cleaning, and when large quantities of a humectant are employed,
the humectant forms a slippery interface between the tooth surface
and the feldspar particles, reducing to some extent the ability of
the feldspar particles to effectively remove stains and the like
from the tooth surface. It has been found that when no more than
about 8% by weight of a humectant is employed, there is
substantially no reduction in the cleaning ability of feldspar
particles.
This low quantity of humectant is sufficient if the paste is not
subject to a long lapse of time before being used. For this reason,
for ordinary use on adults, the paste should be made up shortly
before use, and the amount of humectant be held to no more than
about 8%, instead of having it prepackaged in a form that requires
high percentages such as 25% humectant. This low percent of
humectant not only gives better cleaning, but it reduces or
eliminates the unpleasant oily taste, and as will appear, it
improves the effectiveness of the fluoride adjuvants.
For professional prophylactic use for children, it is not desired
that the prophylactic paste be highly abrasive; hence, such pastes
may be made up in advance and may contain substantial quantities
(e.g., above about 20% by weight) of a humectant such as glycerine
or the like.
Anti-Cariogenic Agent
A particularly important advantage of the present invention is in
dental therapeutics, since the feldspars described are
significantly better with fluoride anticariogenic agents that are
prior art materials. It is possible to get as good or better
anticariogenic effects using the feldspars with much smaller
quantites of fluorides than have heretofore been possible, and to
have more long-lasting protection from caries. It is also possible
to use sodium fluoride as the anticariogenic agent.
Since dental caries is caused, at least in part, by the solution of
enamel in biologically produced acids of the oral cavity, a
decrease in the solubility of enamel in such acids by treating the
enamel with a fluoride can reduce the dental caries incidence. One
measure of the ability of a fluoride to decrease enamel solubility
due to the fluoride treatment is conveniently termed "ESR", meaning
enamel solubility reduction, and will be referred to as such
hereinafter. ESR may be measured by the method set forth in U.S.
Pat. No. 3,257,282, and the same is incorporated herein by
reference.
When used in combination with a fluoride-containing, anticariogenic
adjuvant such as sodium fluoride in aqueous solution, the tendency
of the present feldspar to "deactivate" the fluoride-containing
adjuvant has been substantially nil. Surprisingly, the fluoride
(anticariogenic) activity of sodium fluoride when employed in a
feldspar paste made up shortly before use is equal to and more
persistent or durable in the mouth than that obtained through the
use of a sodium fluoride solution alone, and is much greater than
that obtained with sodium fluoride in combination with a zirconium
silicate or flour of pumice abrasive.
The feldspar used with fluorides should be one low in calcium
(preferably below 2.0%). Apparently the high calcium feldspars form
insoluble calcium fluorides that reduce the quantity of fluoride
that is active in the mouth to reduce caries.
Not only is the anticariogenic effect of the fluoride superior in
the present invention, but it can be obtained using much less of
the adjuvant by weight than with other prior art dental
prophylactic abrasives. This eliminates or at least reduces bad
flavor problems and the nauseating effects of conventional larger
quantities of fluoride-containing adjuvants, especially stannous
fluorides.
Fluoride-containing adjuvants are employed in pastes of the
invention in a sufficient concentration to significantly reduce the
incidence of dental caries in patients. This concentration may
range widely, and depends at least in part upon the nature of the
chosen adjuvant. Sodium fluoride is a preferred fluoride-containing
anticariogenic adjuvant in many uses of the present invention, but
other such adjuvants can be employed in it, such as SnF.sub.2,
SnZrF.sub.6, etc.
In general, satisfactory results may be obtained by employing a
percentage ratio of stannous fluoride-containing adjuvant to
feldspar of from about 1.0 to about 10.0% (all ratios and
percentages in this specification are by weight unless otherwise
apparent), but a range of about 2.0% to about 6.0% is preferred.
With sodium fluoride, a percentage ratio of from about 0.5% to
about 1.0% has given good results and is preferred. Other
constituents may be as indicated elsewhere herein.
Children's Teeth Treatment
In general, the finer particle size ranges of feldspar
(substantially all of which, for example, pass through a 170 mesh
screen) may be preferred for use in the treatment of children's
teeth, since children's teeth require lighter cleaning because of
less persistent stains. An excellent paste low in enamel damage for
cleaning and polishing children's teeth and for a highly effective
fluoride treatment of the teeth includes feldspar particles,
substantially all of which pass through a 170 mesh screen, and a
fluoride-containing anticariogenic adjuvant which is preferably
sodium fluoride. If this paste is to be used by a professional to
clean and fluoride-treat children's teeth, then the paste should be
made up shortly before use and should contain less than about 8% by
weight of a humectant and a somewhat larger quantity of a
fluoride-containing adjuvant. If made long in advance, as for
self-administration, it should contain 20-25% or so of humectant.
In either case, its principal function is as a carrier for topical
application of fluoride.
The Kit
When intended for professional use on adult patients, it is
desirable that the prophylactic paste of the invention contain 8%
by weight or less of a humectant so that thorough cleaning of the
teeth may be effected. This is for reasons above expressed,
including the fact that when mixed long in advance, the fluoride
tends to become lower in effectiveness, especially when substantial
quantities of glycerine are present. When the present mixture is
used at the time of mixing, the ESR in the mouth is much better and
lasts longer. It is to be noted that the depleting effect of
long-term pre-mixing is less with feldspar than with prior art
abrasives, and the term of effectiveness in the mouth is longer.
However, these factors are further improved by mixing the dry
feldspar components with the liquid ones at time of use. The kit
separately contains a source of feldspar as described above and an
aqueous solution of a fluoride-containing anticariogenic adjuvant.
Maintaining the dry and moist components apart eliminates the
problems of caking or other undesirable incidents to pre-mixing, as
noted herein.
A small disposable measuring spoon (or the like) may be provided in
the kit to measure a predetermined quantity of the feldspar (which
may be incorporated with other dry ingredients) and a disposable
calibrated syringe or pipette (or the like) may be provided for
measuring out enough of the solution to be combined with the dry
ingredients to provide a paste or suitable consistency which
contains a dental caries-reducing amount of the anticariogenic
agent.
In a preferred embodiment, the dry paste ingredients, which may
include the feldspar particles, binder, flavoring, coloring,
bleaching agents, and humectant are disposed in one compartment of
a container, and the wet ingredients (including the
fluoride-containing anticariogenic adjuvant, water, and the like)
are disposed in another compartment of the container. Means
normally separating, but providing for communicating the two
compartments, are arranged so that the ingredients thereof may be
mixed to form the desired paste.
For example, a plastic film packet having two adjacent compartments
separated by a rupturable heat seal may contain predetermined
quantities of the wet and dry ingredients in the two compartments,
respectively. Rupture of the rupturable seal, followed by hand
kneading of the contents, will provide a suitable paste. The
quantities of wet and dry ingredients are preferably chosen so as
to provide sufficient paste for at least a single prophylactic
treatment.
The kit affords a flexibility in use in a number of respects. The
dry powder may be combined in one packet with stannous fluoride, in
another with sodium fluoride. In either case the user can select
which adjuvant is desirable, and can add as much as he deems
advisable. Indeed, he can omit the fluoride if it is not desired,
and can add water to the dry powder to make it a paste for use. In
addition, he gets the advantage of mixing at time of use. Also the
manufacturer can make up different packet combinations from a small
number of variations on the components.
The invention may be more easily understood by reference to the
following illustrative, non-limiting examples
EXAMPLE 1
Abrasive slurries made from different particle size ranges of
finely-divided feldspar were compared from the standpoint of
cleaning and polishing of teeth with flour of pumice and with
zirconium silicate slurries.
For the cleaning and polishing evaluations abrasive slurries were
prepared using one part of a 1% CMC-7HF (carboxymethyl cellulose)
solution to one part of abrasive by weight in order to prevent the
abrasive from settling. Commercial prophylactic pastes were
analyzed in this respect by diluting three parts of paste with one
part of water.
Testing was performed on a machine designed specifically for the
purpose. This device has an adjustable constant velocity mandrel to
which the prophy cup is attached, the entirety of which can be
raised and lowered so that the prophy cup can be adjusted to the
desired height. The specimen is contained by four screws in a round
cup, which can be revolved at a constant rate and is positioned on
an adjustable platform which has a weighted arm that enables the
pressure to be set where desired. The prophy cup motor assembly can
be lowered onto the specimen until the force is sufficient to
balance the weighted arm.
Cleaning evaluations were made on 2.0 .times. 2.0 .times. 0.6 cm
black Plexiglas blocks. Tests were run by covering the block with
the abrasive slurry and revolving the prophy cup at 500 rpm and the
specimen cup at 500 rpm for 2 minutes at a pressure of 273 grams.
The prophy cup was lifted every twenty seconds to replenish the
supply of paste underneath it in order to simulate activity during
a normal prophylaxis.
The amount of Plexiglas removed under identical conditions for each
abrasive was taken as an indication of the cleaning ability of each
abrasive and was determined both by weight loss and depth
measurements on a Bendix Proficorder. For the weight loss method
the blocks were thoroughly washed, dried, and vacuum dessicated
before and after treatment. The same blocks were read on the
Proficorder (accuracy .+-. 0.0000015 inches) to determine the depth
of the abrasive scratches made by the prophylaxis treatment. The
Proficorder has a diamond stylus tracer that provides a strip chart
of the microtopography of the specimen to a very high degree of
sensitivity and is a very accurate means of evaluation. The
correlation between these two methods of evaluation is good; the
greater the weight loss, the greater the degree of cleaning; the
deeper the penetration, the greater the degree of cleaning.
Polishing evaluations were made on bovine teeth, mounted in Wood's
metal with the labial surfaces exposed, with a prophy cup on the
machine described above. The labial surface was leveled on a
surface grinder so as to provide a smooth, even area for testing.
In this case, the prophy cup, which was revolving at 500 rpms, was
lowered onto the specimen which was held stationary, immersed in
the abrasive slurry, and maintained in that position for 15
seconds. The degree of polishing was compared to a white carrara
glass standard (arbitrarily designated at 100% reflection) on a
reflectometer and through an X-Y recorder a print-out, showing the
reflectance of the entire tooth surface, was made. The polished
area provides peaks on the chart and these are taken as the enamel
polish (see tables 1 and 2).
Table 1 shows results of the cleaning tests using five commercial
samples and a final sample (IUF 140) of the present invention.
Table 2 compares polishing results for two commercial samples and
four samples of the present invention. The numbers (-140, -170,
-200, -325) in these Tables refer to the screen size through which
the particles could pass.
From Table 1 it is seen that the pumices clean rapidly and deeply,
but with severe scratching as shown by the last column. Zircate is
poorer as a cleaner, and scratches more. The present invention
cleans better than zircate, comparably to pumice, and scratches
less than most pumices.
From Table 2 it is seen that the present invention polishes better
than the other materials.
TABLE 1
__________________________________________________________________________
Plexiglass Cleaning and Enamel Scratching Prophylaxis Paste
Plexiglass Cleaning Avg.Wt.Loss Depth of Pene- Avg.Scratch (mgs)
tration (.mu.ins.) Depth (.mu.ins)
__________________________________________________________________________
Brand A Coarse Pumice 8.7 2675 883 Brand A Medium Pumice 7.1 1913
607 Brand B Pumice 4.1 1067 773 Brand C Pumice 2.9 922 283
Commercial Zirconium Silicate 0.6 66 497 IUF 140* 1.7 512 350
__________________________________________________________________________
* IUF is a paste of the present invention, using -140 mesh
feldspar.
TABLE 2 ______________________________________ Enamel Polish
Abrasive System Avg. Enamel Polish
______________________________________ Zirconium Silicate 83% Flour
of Pumice 83% Feldspar F-4 (-140) 92% Feldspar F-4 (-170) 90%
Feldspar F-4 (-200) 95% Feldspar F-4 (-325) 95%
______________________________________
EXAMPLE 2
A test was made to compare cleaning test blocks with feldspars of
different particle sizes. The feldspars were mixed 1:1 with a 1%
CMC-7HF solution, mechanically tried with prophy cups given a fixed
load and operated at a fixed relative speed for a given time. The
results, averaging four runs in each case:
-140 mesh feldspar - 4.1 avg. weight loss
-170 mesh feldspar - 4.4 avg. weight loss
-200 mesh feldspar - 4.0 avg. weight loss
-325 mesh feldspar - 3.0 avg. weight loss
These tests show that a wide range of particle sizes gives useful
and comparable cleaning results.
Polishing results with the same feldspar mixes developed the
following comparisons, each being an average of four bovine teeth
tests:
-140 mesh, percent reflectivity 87
-170 mesh, percent reflectivity 87
-200 mesh, percent reflectivity 93
-325 mesh, percent reflectivity 94
These results are all comparable.
In another test for cleaning ability, different particle sizes of
feldspar were mixed 1:1 with a 1% CMC-7HF solution, tested with
prophy cups on black Plexiglas, the prophy cups being uniformly
loaded and operated at a uniform relative rotation speed for
uniform time. The results, in each case, show an average
dessication weight loss of three samples; in the second column
after three days; in the third column after seven days:
-440 mesh feldspar 1.8 2.5 -170 mesh feldspar 1.7 2.2 -200 mesh
feldspar 1.6 2.4 -325 mesh feldspar 2.0 2.9
The comparability of these results is evident, and accordingly any
of that entire range of particle sizes can be used to obtain good
cleaning effect.
EXAMPLE 3
A cleaning test was made to compare cleaning by -140 mesh feldspar,
flour of pumice, and zirconium silicate. The cleaning test was
conducted similarly to that in Example 1. The results are as
follows (in each case an average of three samples):
ZrSiO.sub.2 0.7 weight reduction -140 mesh feldspar 2.8 weight
reduction
EXAMPLE 4
A prophylactic paste containing 20.3 of humectant was prepared as
follows:
To a mixture of Water 19.5 parts Cabosil (finely-divided silica, a
product of Cabot) 0.3 parts Sodium fluoride 2.0 parts and
Meta-phosphoric acid 4.0 parts was added a mixture of IUF -140 or
-170 49 parts Saccharin 0.3 parts Titanium Dioxide (bleach) 2.0
parts
To the resulting mixture was added the following which had been
pre-heated to a temperature of 70.degree.C:
Veegum (magnesum aluminum silicatae as a binder) 0.25 parts and
Sorbitol (70%) 2.8 parts and to this was then added, in sequence, a
mixture of Propylene Glycol 12.75 parts Peppermint flavoring 0.8
parts and Sodium Lauryl sulfate 0.5 parts Coloring 0.8 parts
Carboxy methyl cellulose (CMC-7HF), a product of Hercules) 0.5
parts and Glycerin 4.75 parts The amount of meta phosphoric acid
used was that amount required to adjust the pH to 4.5.
TABLE 3 ______________________________________ Enamel Solubility
Reduction Paste ESR (%) ______________________________________
Prophy paste for children (20% humectant) (0.91% F-) 23.3
______________________________________
This paste, which contains only 0.91% of fluoride as NaF, is
suitable for use as a prophylactic paste for children. The level of
humectant prevents undue erosion of hard tooth structure, but the
level of NaF provides a high reduction in enamel solubility (see
Table 3).
EXAMPLE 5
In compounding a prophylactic, feldspar-containing powder low in
humectant that provided excellent laboratory and clinical results,
the following formulation was prepared, amounts being expressed in
percent by weight:
To a mixture of -140 Mesh Feldspar F-4 93.5% Titanium Dioxide 1.9
Hydroxyethyl cellulose 0.2 Saccharin 0.25 was added a solution of
Propylene glycol 3.7 Peppermint oil 0.5
Four grams of thus-prepared powder were added to 1.0 ml of either a
SnF.sub.2 or NaF solution and thoroughly stirred to provide
adequate paste for a single prophylaxis. The stannous fluoride
solution is prepared fresh by dissolving 0.3 grams of SnF.sub.2 in
1.0 ml of water. The sodium fluoride was used as a stable 4%
solution. This provides 1.38% fluoride as SnF.sub.2 (5.66%
SnF.sub.2) and 0.36% fluoride as NaF (0.8% NaF).
After thorough mixing, the resulting paste was employed in a
prophylactic treatment of a human patient (see Table 4). In
comparison with other prophylactic pastes, very little slinging was
noted.
TABLE 4 ______________________________________ Enamel Solubility
Reduction (ESR) Prophylaxis Pastes with NaF Paste ESR (%)
______________________________________ Commercial Brand Pumice
(1.23% F-) 2.0 Commercial Brand Pumice (1.81% F-) 24.1 IUF -140
(0.36% F-) 46.2 Prophylaxis Pastes with SnF.sub.2 IUF -140 (5.7%
SnF.sub.2) 72.3 Zirconium Silicate (9% SnF.sub.2) 54.4
______________________________________
EXAMPLE 6
A test was made to determine whether, with feldspar, the quantity
of fluoride could be lowered without seriously reducing the ESR.
Treating teeth with a saturated solution of SnF.sub.2 produced
ESR's of 91% and 88%. Reducing the amount of SnF.sub.2 by 60%, and
80%, respectively, resulted in ESR's of 99% and 90%, respectively,
thus showing that with the feldspar, less fluoride can be used.
Other tests have shown comparable results.
EXAMPLE 7
A heat-sealable section of polyethylene film was cut into two
segments, each measuring 1 inch by 2 inches. One of the segments
was placed on a flat surface and a line was drawn perpendicular to
the longest dimension of the sample so as to visually divide the
sample into two 1-inch squares. Onto one of the squares was
deposited 4.0 grams of the "dry" mixture referred to in Example 5
above, and the second 1-by-2 inch segment of film was then placed
upon the first section of film and the edges thereof were
heat-sealed together to provide a plastic pouch containing the "dry
mixture". A final heat seal between the upper and lower segments of
film was placed along the pencil line dividing the lower film
sample into two 1-inch sections, this heat seal being one-fourth
inch wide except for a portion of its length wherein the heat seal
was only 1/16 inch wide. The resulting pouch thus was divided into
two compartments, one of which contained the dry material. By means
of a hypodermic syringe, 1.0 milliliter of the "wet" mixture of
components referred to in Example 5 above was injected into the
empty compartment, and upon removal of the syringe, the pin hole
therein was heat-sealed to render that compartment watertight. The
heat seals about the edges of the two film segments were
approximately one-fourth inch in width.
The compartment of the resulting pouch holding the wet mix was then
pinched to rupture the one-sixteenth inch heat seal between the
compartments permitting the wet mixture to contact the dry mixture.
By manipulating the pouch with the fingers, the wet and dry
mixtures were thoroughly mixed together to provide a prophylactic
paste suitable for use in the cleaning and polishing of teeth.
In some of the foregoing tests, run at Indiana University,
artificial surfaces, or bovine teeth, were used. The results are
intended to be comparative rather than absolute.
The invention has been described above with reference to certain
exemplary embodiments. It will be understood, of course, that
modifications and variations of the invention as hereinabove set
forth may be made without departing from the spirit and scope of
the present invention, which is limited only by the claims which
follow.
* * * * *