IMPROVEMENTS. IN ATTACHING ARTIFICAL TEETH TO PLATES AND TO EACH OTHER, AND IN MOULDS FOR FORMING ARTIFICIAL TEETH
Year: 1862

page_text: ETTERS PATENT to George Davies, of No. 1, Serle Street, Lincoln's
Inn, in the County of Middlesex, and No: 28, St. Enoch Square, in the
City of Glasgow, Civil Engineer and Patent Agent, for the Invention
of "IMPROVEMENTS. IN ATTACHING ARTIFICAL TEETH TO PLATES AND TO EACH
OTHER, AND IN MOULDS FOR FORMING ARTIFICIAL TEETH."A communication
from abroad by Abraham Merritt Asay and Jacob Lambert Asay, both
of the City of Philadelphia, Pennsylvania, in the United States of
America.
Sealed the 5th September 1862, and dated the 11th March 1862.
PROVISIONAL SPECIFICATION left by the said George Davies at the
Office of the Commissioners of Patents, with his Petition; on the 11th
March 1862.
I, GEORGE DAVIES, of No. 1, Serle Street, Lincoln's Inn, in the County of
Middlesex, and No. 28, St. Enoch Square, in the City of Glasgow, Civil
Engineer and Patent Agent, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN ATTACHING ARTIFICIAL TEETH TO PLATES AND TO EACH
OTHER, AND IN MOULDS FOR FORMING ARTIFICIAL TEETH," to be as follows:-
The first part of this Invention consists in securing, artificial teeth to metal
plates, by interposing between the said teeth and plates a strip or mass of
gum, and vulcanizing, or hardening the same after the teeth have been
adjusted to the plate, as fully described hereafter. Also in forming. dovetailed

page_text: recesses in artificial teeth, substantially as described hereafter, for the purpose
of securely attaching the teeth to the plate and to each other, by vulcanizable
gum, or any other suitable cement. Also in the use of staples embedded in
artificial teeth, as a means of securing the latter to vulcanizable gum plates,
in the manner described hereafter.
The second part of the Invention consists in making moulds for forming
artificial teeth, substantially as described hereafter, so that depressions of any
size or shape may be formed in the bases of the teeth. In attaching teeth to
a metal plate by means of vulcanizable gum, a plate of the desired form is
first prepared by any of the known processes, and at the point where the teeth
have to be secured a metal rib is soldered or otherwise secured to the plate.
This rib may be plain, but it is preferable to make it thicker on the outer
edge than it is at the point where it is secured to the plate, or the rib may be
perforated or serrated. In the teeth or block of teeth, as the case may be, is
formed a groove or recess to coincide with the rib or projection of the plate,
the groove being somewhat larger than the rib and dovetailed, as explained
hereafter. A strip or sheet of vulcanizable gum is placed over the rib of the
plate, care being taken to keep both the teeth and plate warm. The teeth
are now applied to the plate and pressed tightly against the same, so that the
rib of the plate may penetrate the groove of the teeth, carrying with it a suffi-
cient quantity of gum to make a tight joint, and to fill up all irregularities or
interstices. The whole is then placed in a mixture of plaster of Paris and
whiting, and the gum subjected to a vulcanizing or hardening process,
the block of teeth will be found to adhere with the required tenacity to the
plate, the interstices in the block and between the block and plate being
filled with the vulcanized gum, and the joint presenting a smooth and uniform
appearance. Instead of using a rib of metal on the plate, the surface of the
plate at the point where the block has to be attached may be chipped, ser-
rated, or otherwise roughened for receiving the strip of vulcanizable gum,
although the use of the rib is preferable, as it tends to afford, with the gum, a
more secure fastening.
when
In securing the teeth to the plates by the usual process of rivetting or
soldering, numerous interstices and angular cavities are formed between the
teeth and the plate, and between the teeth themselves. These are packed
with a vulcanizable gum, which is subjected to the hardening process after the
packing has been properly adjusted, so that all cavities and irregularities are
fitted with a durable and immovable packing.
The method of securing artificial teeth to vulcanizable gum plates is as
follows: To a block of (say) three teeth are connected three staples made of

page_text: platina or other wire capable of resisting ordinary heat; heads or notches are
formed on the two ends of the wire which compose each staple, and these
beads are imbedded in the material of which the teeth are formed, while the
said material is in a plastic state, and is being reduced to the desired shape
by the ordinary moulds, or otherwise, so that when the teeth are properly
baked the heads will render the withdrawal of the staples without breaking
the teeth impossible. The staples extend beyond the rear of the teeth, so that
the
gum
while still in a plastic state, and prior to the vulcanizing of the same,
may be forced between the rear of the teeth and the bent portion of the
staples, the projecting portions of the latter being thus thoroughly imbedded
in the gum.
. The second part of the Invention, which relates to moulds for forming
artificial teeth especially applicable for attachment to plates by vulcanizable
gum, is as follows:-In the lower portion or base of the moulds are cut
recesses of the desired shape for forming the lingual surface of the teeth..
This lower portion of the moulds is cut away or recessed at the opposite ends
for the reception of blocks, the latter being inclined at the bottom, and
adapted to the inclination of the recesses in which the said blocks.can be
slidden freely to and fro. From the ends of each recess of the lower portion
of the mould project small rods, which passing through the blocks serve the
double purpose of guiding the latter, and of retaining them in the position to
which they have been adjusted. Supplementary blocks or plates are to be
placed (under circumstances alluded to hereafter) between the blocks and the
ends of each recess of the lower portion of the moulds, these blocks having
holes through which pass the projecting rods above mentioned. In the under
surface of the upper portion or cap of the mould are cut the depressions for
forming the labial surface of the teeth. This portion of the mould is bevilled
on the under side and at the opposite ends, and adapted to the bevilled tops
of the blocks, which are arched, and adapted to the arched under sides of the
bevilled ends of the upper portion of the mould, and this arch is of a shape to
correspond with the block of teeth to be formed in the mould.
5
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said George Davies in the Great Seal. Patent Office on the
11th September 1862.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
DAVIES, of No. 1, Serle Street, Lincoln's Inn, in the County of Middlesex,
5
11th September 1862.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
DAVIES, of No. 1, Serle Street, Lincoln's Inn, in the County of Middlesex,

page_text: and. No. 28, St. Enoch Square, in the City of Glasgow, Civil Engineer and
Patent Agent, send greeting.
:
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eleventh day of March, in the year of our Lord One
thousand eight hundred and sixty-two, in the twenty-fifth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
George Davies, Her special licence that I, the said George Davies, my
executors, administrators, and assigns, or such others as I, the said George
Davies, 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 "IMPROVEMENTS IN. ATTACHING
ARTIFICIAL TEETH TO PLATES AND TO EACH OTHER, AND IN MOULDS FOR FORMING
ARTIFICIAL TEETH," a communication to me from abroad by Abraham Merritt
Asay and Jacob Lambert Asay, both of the City of Philadelphia, Pennsylvania,
in the United States of America, upon the. condition, amongst others,
that I, the said George Davies, my executors or administrators, by an
instrument in writing under my, or their, or one of their hands and seals,
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 George Davies, 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
in writing, and on reference to the accompanying Drawings, that is to say:-
The first part of this Invention consists in securing artificial teeth to metal
plates, by interposing between the said teeth and plates a strip or mass of
gum or india-rubber, and vulcanizing or hardening the same after the teeth
have been adjusted to the plate; as fully described hereafter. Also in forming
dovetailed recesses in artificial teeth, substantially as described hereafter, for
the purpose of securely attaching the teeth to the plate and to each other by
vulcanizable gum or any other suitable cement. Also in the use of staples
embedded in artificial teeth, as a means of securing the latter to vulcanizable.
gum plates, in the manner described hereafter.
The second part of the Invention consists in making moulds for forming
artificial teeth, substantially as described hereafter, so that depressions of any
size or shape may be formed in the bases of the teeth... In attaching teeth to

page_text: a metal plate by means of vulcanizable gum, a plate of the desired form is
first prepared by any of the known processes, and at the point where the teeth
have to be secured a metal rib is soldered or otherwise secured to the plate.
This rib may be plain, but is preferable to make it thicker on the outer edge
than it is at the point where it is secured to the plate, or the rib may be per-
forated or serrated. In the teeth, or block of teeth, as the case may be,
is formed a groove or recess to coincide with the rib or projection of the plate,
the groove being somewhat larger than the rib and dovetailed, as explained.
hereafter. A strip or sheet of vulcanizable gum is placed over the rib of the
plate, care being taken to keep both the teeth and plate warm. The teeth;
are now applied to the plate and pressed tightly against the same, so that the
rib of the plate may penetrate the groove of the teeth, carrying with it a
sufficient quantity of gum to make a tight joint, and to fill up all irregularities
or interstices. The whole is then placed in a mixture of plaster of Paris and
whiting, and the gum subjected to a vulcanizing or hardening process, when⚫
the block of teeth will be found to adhere with the required tenacity. to the
plate, the interstices in the block and between the block and pláte being filled
with the vulcanized gum, and the joint presenting a smooth and uniform
appearance. Instead of using a rib of metal on the plate, the surface of the
plate at the point where the block has to be attached may be chipped, ser-
rated, or otherwise roughened for receiving the strip of vulcanizable gum,
although the use of the rib is preferable, as it tends to afford, with the gum, a
more secure fastening.
In securing the teeth to the plates by the usual process of rivetting or
soldering, numerous interstices and angular cavities are formed between the.
teeth and the plate, and between the teeth themselves. These are packed.
with a vulcanizable gum, which is subjected to the hardening process after the.
packing has been properly adjusted, so that all cavities and irregularities are
fitted with a durable and immoveable packing.
Such being the nature and object of the said Invention for "Improvements.
in Attaching Artificial Teeth to Plates and to each other, and in Moulds for:
forming Artificial Teeth," I will now proceed to describe more in detail the
manner in which the same is to be or may be performed or carried into
practical effect; & in order that the same may be distinctly understood, I
have annexed hereunto a Sheet of Drawings illustrative thereof, and have
marked the same with figures and letters of reference corresponding with
those in the following explanation thereof, that it to say :-
In the accompanying Drawing, Figure 1 is a plan view of the plate, with
some of the teeth secured to the same; Figure 2, a transverse section on the:

page_text: line 1, 2, Figure 1; Figure 3, a transverse section on the line 3, 4, Figure 1;
Figures 4, 5, and 6, sectional views illustrating modifications of the improve-
ments.
A is a plate prepared in the usual manner, and near the edge of this plate,
at the point where the teeth have to be secured, is attached a rib or projection
a,
, which is serrated or perforated with a number of holes as seen in Figure 2.
In the present instance the teeth to be attached to the plate are made in
sections, each section having one, two, or three teeth, and having a dovetailed:
recess, seen in Figure 3,' for receiving the perforated or serrated rib a, the
said recess being somewhat wider than the rib. At the end of each section of
teeth another recess communicating with the above-mentioned recesses is:
formed, so that at the point where two sections meet the end recesses of one:
will coincide with that of the other, the two recesses forming a dovetailed
chamber shown at x, Figure 2. In securing the teeth to the plate any
vulcanizable gum may be used as a cement, the gum being deposited while in
a plastic state in the recesses of the sections, as well as in the dovetailed.
chambers a, formed between the sections. A strip of the same material is
also placed on the plate at the points where the teeth have to be secured. The
blocks are held in their proper position during the process of vulcanizing the
gum by means of plaster of Paris and whiting, after which they will be securely
attached to the plate as well as to each other, inasmuch as the gum penetrating.
the perforations or serrations of the rib a, effectually confines the latter to.
the dovetailed recesses of the blocks of teeth, and at the same time the har-
dened gum having penetrated the dovetailed chamber a renders the removal
of one block without disturbing the whole almost impossible. In place of
vulcanizable gum any silicious or other cement, capable of being reduced to a
plastic or fluid state, and subsequently hardened, may be advantageously used;
and in place of the rib a, a simple perforated, notched, or serrated projection
y, Figure 5, is used, the projection being soldered or otherwise secured to the
plate, one of these projections being situated at the point where two sections
meet each other, and one or more between these points, as seen in Figure 4,
and dovetailed recesses being formed in the sections for the reception of these
projections, and the cement being deposited in these recesses. It will be
evident that the result as regards the securing of the teeth to the plate and
to each other will be precisely the same as that above described in reference
to Figures 1, 2, and 3. Occasionally it may be necessary to secure a single
tooth instead of a section to the plate, in which case a single-recess in the
tooth and one projection on the plate, as seen in Figure 6, are adopted. - The
method of securing artificial teeth to vulcanizable gum plates is illustrated in:

page_text: Figures 7, 8, and 9. Figure 7, representing the inside view of a block of
artificial teeth with the staples; Figure 8, a sectional plan on the line 5, 6;
Figure 9, a transverse section, with a modified arrangement of staples. E
represents a block of three teeth, to which are connected the two staples e, é,
made of platina or other wire capable of resisting ordinary heat, the form of
the staples being shown in Figure 8; heads or notches are formed on the two
ends of the wire which compose each staple, and these heads are imbedded in
the material of which the teeth are formed, while the said material is in a
plastic state, and is being reduced to the desired shape by the ordinary moulds
or otherwise, so that when the teeth are properly baked, the heads will render the
withdrawal of the staples without breaking the teeth impossible. It will be
seen that the staples extend beyond the rear of the teeth, so that the gum
while still in a plastic state, and prior to the vulcanizing of the same, may be
forced between the rear of the teeth and the bent portion of the staples, the
projecting portions of the latter being thus thoroughly imbedded in the gum.
After the latter has been vulcanized by the usual process, and thereby reduced
to the well known tough and hard state, it will be impossible to detach the
teeth from the gum plate without tearing or disintegrating the latter or breaking
the staples or teeth, the projecting portions of which are imbedded in, surrounded,
and held by the vulcanizable gum. In some cases the staples may be attached
to the teeth in the manner shown in Figure 9, where a mass of vulcanizable
gum is secured to a plate A, and the staple imbedded in that gum, which thus
forms the rear of the teeth; in fact, the disposal and number of staples used
will in a great measure depend upon the form and size of the teeth or the
extent of the block of teeth.
The second part of the Invention which relates to moulds for forming
artificial teeth, especially applicable for attachment to plates by vulcanizable
gum, is illustrated by Figures 10, 11, 12, and 13; Figure 10 being a side
view partly in section of the improved moulds; Figure 11, a plan view with
the upper portion of the mould removed. Figure 12, an end view; Figure 13,
detached views of part of the improved mould.
A is the lower portion or base of the moulds, in which are cut recesses a, a,
of the desired shape for forming the lingual surface of the teeth. This lower
portion A of the moulds is cut away or recessed at the opposite ends for the
reception of the blocks B, B, the latter being inclined at the bottom and adapted
to the inclination of the recesses in which the said blocks can be slidden freely
to and fro. From the ends of each recess of the lower portion of the mould
project the rods, which passing through the blocks B, B, serve the double
purpose of guiding the latter, and with the pins t, t, of retaining them in the

page_text: position to which they have been adjusted. C, C, are supplementary blocks
or plates to be placed (under circumstances alluded to hereafter) between
the blocks B and the ends of each recess of the lower portion of the moulds,
these blocks having holes thro' which pass the projecting rods x, a. Dis
the upper portion or cap of the mould, into the under surface of which are cut
the depressions for forming the labial surface of the teeth. This portion D-
of the mould is bevilled on the under side and at the opposite ends, as seen at
y, y, Figure 10, and adapted to the bevilled tops of the blocks B, which, as
seen in the end view, Figure 12, are arched and adapted to the arched under
sides of the bevilled ends of the upper portion of the mould, and this arch is
of a shape to correspond to the block of teeth to be formed in the mould:
Through openings in the pieces B project pins c, c, the use of which will be
more fully explained hereafter.
Supposing that the parts of the mould are in the relative position shown in
the Drawing, the supplementary pieces C, C, having been removed from one
end of the mould, the material of which the teeth are to be formed is introduced
in a plastic state into the lower portion of the mould, over which is fitted the
cap
D ; pressure is then applied until the upper and lower portion of the mould
are brought into contact with each other, the material being thus forced into
every portion of the mould, while all excess of the material is pressed out at
the sides. The pins c are then introduced, and pushed forward until their
heads come in contact with the end of the block B. After the mould has
been subjected to a heat sufficient to evaporate all the moisture from the
material, the pins c and t are removed, the pieces B and C sliden away, after
which the two parts A and D of the mould can be separated, and the com-
pleted block of teeth readily removed.
On reference to Figures 10 and 11, it will be seen that that the pieces B have
a rounded projection m, which makes à depression along the whole length of
the base of the block of teeth, so that the latter could not be withdrawn
from the mould without first drawing away the pieces B. In ordinary moulds
which are formed of but two pieces, it is necessary to make the bases of the
block of teeth either bevilled or slightly curved, as seen in Figure 14, in order
that they may be removed from the mould.
The advantages of the pieces B, B, will be apparent when it is considered
that the 'blocks of teeth procured at the wholesale manufacturers are of the
form shown in Figure 14, and that it is necessary to grind away a portion
of the block until it assumes the form shown in Figure 15, an- operation
requiring nice and tedious manipulation.
In extensive establishments for the manufacture of artificial teeth, a new

page_text: mould is required for every different size of block, and in many cases this
difference in size is demanded by an increase in or diminution of the length
of the
gum, without any necessity for altering the shape of the teeth.
By sliding back the pieces B, B, and introducing pieces C, C, blocks of
teeth of any required size may be cast from one mould, so far as the length of
the gum is concerned, while the recess for fitting over the alveolar process on
the plate may be made of any required shape by making the projecting
portion m of the piece B of the desired form..
After the blocks are taken from the moulds, in which condition they are
very fragile, it is necessary to drill holes perpendicular to the base, through
which rivets may be passed to secure them to; the plate. To prevent the
risk of cracking the teeth incurred by this operation, we form the desired
holes by introducing into the material in its plastic state the pins e, e, which
remain until the block is hard enough to be removed from the mould, when
they are withdrawn. This method of lengthening the bases and forming
the depressions at the base may be also applied to single teeth as well as to
those cast in blocks of two or more: The supplementary pieces C, C, may be
dispensed with, and the blocks B, B, rendered adjustable by means other than
those described.
• Figure 16 représents a section, Figure 17 a plan view, and Figure 18 an
end view of a modification of the above, wherein the supplementary blocks C, C,
are dispensed with..
Having now described the nature and object of the said Invention for
Improvements in Attaching Artificial Teeth to Plates, and to each other,
and in Moulds for Forming Artificial Teeth," together with the manner in
which the same is to be or may be performed or carried into practical
effect, I would remark, in conclusion, that I claim as the Invention com-
municated to me by the aforesaid Abraham Merritt Asay and Jacob
Lambert Asay,
Firstly, fastening artificial teeth to metallic plates by interposing between
the said teeth and plate a strip of vulcanizable gum; and vulcanizing or
hardening the same after the teeth have been adjusted to the plate, as herein
set forth.
Secondly, packing with vulcanizable gum the interstices between the teeth
and plate, or between the teeth themselves, where the latter are secured to the
plate by rivetting or any other of the usual modes, and vulcanizing or
hardening the packing after it has been adjusted as specified.
Thirdly, dovetailed recesses formed in artificial or blocks of artificial teeth,
in combination with perforated, serrated, or notched ribs or projections on the

page_text: plate, so that the teeth may be firmly secured to the plate through the inter-
vention of vulcanizable gum, or any silicious or other suitable cement, as
herein set forth.
Fourthly, forming in artificial teeth, or blocks of teeth at the point where
they meet each other, dovetailed recesses of such a form that vulcanizable
gum or other cement introduced into the said recesses will prevent the sepa-
ration of said teeth or said blocks from each other as specified.
Fifthly, the use of staples imbedded in artificial teeth as a means of securing
the same to vulcanized gum plates, or to masses of vulcanizable gum attached
to metal plates as described.
Sixthly, so constructing moulds for artificial teeth, that by means of the
adjustable pieces B, B, blocks of teeth of any required depth of gum may be
formed in the same mould.
Seventhly, the use of a moveable piece B with its projection m for the
purpose of forming a depression of any required form in the base of the block
of teeth.
Eighthly, the combination of the base A and cap D of the mould with the
moveable pieces B, guide rods x, and pins e, the whole being arranged sub-
stantially as and for the purpose set forth.
And, ninthly, I claim the modification of the above exhibited in Figures 16,
17, and 18, or any other mere modification thereof, constructed and operating
in substantially the same manner.
In witness whereof, I, the said George Davies, have hereunto set my
hand and seal, this Eleventh day of September, in the year of our
Lord One thousand eight hundred and sixty-two.
GEORGE DAVIES.
GEORGE DAVIES
(IS)