IMPROVEMENTS IN THE PLATES OF ARTIFICIAL TEETH
Year: 1855

page_text: LETTERS PATENT to Charles Goodyear, jun, of No. 42, Avenue Gabriel,
Champs Elysées, in the City of Paris, for the Invention of "IMPROVEMENTS
IN THE PLATES OF ARTIFICIAL TEETH."
Sealed the 8th May 1855, and dated the 14th March 1855.
PROVISIONAL SPECIFICATION left by the said Charles Goodyear, jún","
at the Office of the Commissioners of Patents, with his Petition, on the
14th March 1855.
I, CHARLES GOODYEAB, jun', of No. 42, Avenue Gabriel, Champs Elysées,
in the City of Paris, do hereby declare the nature of the Invention for
"IMPROVEMENTS IN THE PLATES OF ARTIFICIAL TEETH" to be as follows:-
This Invention consists of constructing the plates of artificial teeth of the
hard product obtained by compounding india-rubber or gutta percha (with or
without other matters) with sulphur, and subjecting the same to a high tempe-
rature. For this purpose I take an impression from the mouth of the patient
(in the manner usually practised by dentists) with wax or suitable plastic
material, from which impression I take a cast in plaster of Paris. Upon this
model I carefully adjust teeth of the form and size required, and in the position
which I wish them afterwards to occupy in the mouth of the patient, using
wax or other plastic substance to retain them in the proper position. I then
spread a thin coat or layer of wax over portions of the model, of the form and

page_text: thickness required, which layer of wax represents a model of the plate of
caoutchouc which is afterwards to support the teeth and keep them firm in the
mouth. When the crevices or cavities in or between the teeth are filled up
with the wax, and the model of the plate completed, I take a plaster cast from
the same, which cast I prefer should be enclosed in an iron rim or box for the
purpose of strength. This, when completed, together with the original plaster
model (which I also prefer should be in an iron rim), form a mould which I
use in the following manner :-
After removing the wax from the cavities and crevices in or between the
teeth, I readjust the teeth in their proper positions in the mould. I then fill
up the cavities and crevices and other vacant space in the mould with caout-
chouc or gutta percha suitably prepared with sulphur, and after putting the
several parts of the mould together and subjecting them to a sufficient degree
of pressure, I cause the whole, that is to say, the mould containing the teeth
with the caoutchouc or gutta percha, to be subjected to heat to convert the
compound into the hard product. To obtain a suitable colour, I mix with the
caoutchouc or gutta percha vermillion, oxides of zinc or iron, or any colouring
substance which will stand the necessary degree of heat with the action of the
sulphur. The best compound I believe to be one pound of india-rubber or
gutta percha, or of the two combined in suitable proportions, with half a
pound of sulphur, together with a suitable quantity of colouring matter.
I sometimes find it convenient to substitute the material for the masticators
or teeth hidden from view, for which purpose the material is well fitted from
its extreme hardness and durability. In order that the teeth may be more
firmly attached to the plate, I prefer that they should be jagged or rough, or
have small cavities in the roots or parts imbedded in the plates.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Charles Goodyear, junior, in the Great Seal Patent Office
on the 11th September 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES S
GOODYEAR, junior, of No. 42, Avenue Gabriel, Champs Elysées, in the City
of Paris, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourteenth day of March, in the year of our Lord
One thousand eight hundred and fifty-five, in the eighteenth year of Her 3

page_text: reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Charles Goodyear, Her special licence that I, the said Charles
Goodyear, my executors, administrators, and assigns, or such others as I,
the said Charles Goodyear, my executors, administrators, and assigns, should
at any time agree with, and no others, from time to time and at all times
thereafter during the term therein expressed, should and lawfully might
make, use, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for "Iм-
PROVEMENTS IN THE PLATES OF ARTIFICIAL TEETH," upon the condition (amongst
others) that I, the said Charles Goodyear, by an instrument in writing under
my hand and seal, should particularly describe and ascertain 'the nature of
the said Invention, and in what manner the same was to be performed,
and cause the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Charles Goodyear, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement thereof (that is to say) :-
This Invention consists of constructing the plates of artificial teeth of the
hard product obtained by compounding india-rubber or gutta percha (with or
without other matters) with sulphur, and subjecting the same to a high tempe-
rature. For this purpose I take an impression from the mouth of the patient
(in the manner usually practised by dentists) with wax or suitable plastic.
material, from which impression I take a cast in plaster of Paris. Upon this
model I carefully adjust teeth of the form and size required, and in the position
which I wish them afterwards to occupy in the mouth of the patient, using
wax or other plastic substance to retain them in the proper. position. I then
spread a thin coat or layer of wax over portions of the model, of the form and
thickness required, which layer of wax represents a model of the plate of caout-
chouc which is afterwards to support the teeth and keep them firm.in the
mouth. When the crevices or cavities in or between the teeth are filled up
with the wax, and the model of the plate completed, I take a plaster cast from
the same, which cast I prefer should be enclosed in an iron rim or box for the
purpose of strength. This, when completed, together with the original plaster
model (which I also prefer should be in an iron rim), form a mould which I
use in the following manner :-
After removing the wax from the cavities and crevices in or between the
teeth, I readjust the teeth in their proper positions in the mould. I then fill

page_text: up the cavities and crevices and other vacant space in the mould with caout-
chouc or gutta percha suitably prepared with sulphur, and after putting the
several parts of the mould together, and subjecting them to a sufficient degree
of pressure, I cause the whole, that is to say, the mould containing the teeth
with the caoutchouc or gutta percha, to be subjected to heat, to convert the
compound into the hard product. To obtain a suitable colour, I mix with the
caoutchouc or gutta perchia vermillion, oxides of zinc or iron; or any colouring
substance which will stand the necessary degree of heat with the action of the
sulphur. The best compound I believe to be one pound of india-rubber or
gutta percha, or of the two combined in suitable proportions, with half a
pound of sulphur, together with a suitable quantity of colouring matter.
I sometimes find it convenient to substitute the material for the masticators
or teeth hidden from view, for which purpose the material is well fitted from
its extreme hardness and durability. In order that the teeth may be 'more
firmly attached to the plate, I prefer that they should be jagged or rough, or
have small cavities in the roots or parts imbedded in the plates.
Having thus described the nature of the said Invention, I have only further
to state, that in thus making improvements in artificial plates and teeth of
india-rubber and gutta percha compounds, combined with sulphur, 'that whilst
in the moulds I cause the materials and the moulds to be subjected to heat
for about six hours, and in doing so I gradually raise the heat up to about 230°
of Fahrenheit, say, in about half an hour, and then, unless there be a con-
siderable quantity of foreign matter present, the heat may be raised as quickly
as may be to about 295° of Fahrenheit; otherwise I raise the heat more slowly,
and retain the compound at about that temperature for the remainder of the
six hours, and then allow the whole to cool down, when the process will be
completed. The artificial plates or teeth thus formed will then be ready to be
trimmed and fitted.
I claim the above-described manufacture of artficial plates and teeth.
In witness whereof, I, the said Charles Goodyear, have hereunto set my
hand and seal, this Eighth day of September, in the year of our
Lord One thousand eight hundred and fifty-five.
Witness,
FANNY GOODYEAR.
CHAS GOODYEAR, Jr. (L.S.)