AN IMPROVED PROCESS AND APPARATUS FOR THE MANUFACTURE OF DENTAL PLATES
Year: 1879

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention of
66
AN IMPROVED PROCESS AND APPARATUS FOR THE MANUFACTURE OF DENTAL
PLATES." A communication from abroad by Luigi Noël Winderling, Gustavo
Noël Winderling, and Luciano Noël Winderling, all of Milan, Italy.
COMPLETE SPECIFICATION filed by the said William Robert Lake at the
Office of the Commissioners of Patents on the 14th January 1879.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "AN IMPROVED PROCESS AND APPARATUS FOR
THE MANUFACTURE OF DENTAL PLATES." A communication from abroad by Luigi
Noël Winderling, Gustavo Noël Winderling, and Luciano Noël Winderling, all of
Milan, Italy.
This Invention relates to an improved process for the manufacture of dental
plates or plates for artificial teeth, and to apparatus for carrying the same into
practice.
The said improved process is carried into effect as follows, that is to say:-A
dental plate having been made of wax in the ordinary mauner, is placed within a
heater or heating box of suitable construction by the aid of small cylinders of wax,
which pass through the walls of the heating box in different places. The heating
box is usually constructed of metal. Then plaster or similar inaterial is poured in
until the space between the wax model and the interior walls of the heating box is
quite full. After a certain time the plaster becomes solid, and will have received the
shape of the wax model and the said small wax cylinders; then by suitably heating
the heating box the wax will melt and escape through the holes corresponding with
these cylinders. The teeth, which were previously held together by the wax, will
now be held by the plaster, which must therefore surround them, and enter the
interstices between them. Thus, preparation is made for the reception of the sub-
stauce or material which is to be employed for permanently fixing the teeth
together, and which is to form the base or plate for the set of teeth.
When plastic
material, such as celluloid or caoutchouc, is employed for this purpose this material
may be pressed into the interior of the plaster mould through one of the apertures
provided in the walls of the heating box by means of any suitable apparatus, so as
to entirely fill the spaces left by the melting of the wax. When the substance or
material to be employed is soluble or is liquified by fusion or mixed with a liquid,

page_text: and is capable of being hardened by evaporation or by other means, it is poured
into the plaster mould through the aforesaid apertures in the heating box.
In order to finish or complete the dental plate it is only requisite to disengage it
from the plaster, and to polish it after having cut away the parts corresponding to
the small wax cylinders which served to fix it in the heating box.
The construction of the apparatus employed in practising this Invention may bo
varied; it may be of any suitable form and dimensions, and of any suitable material,
but the construction preferred is shown in the accompanying Drawing, which I will
now proceed to describe.
Figure 1 is a side elevation of the said apparatus or injector; Figure 2 is an end
view; and Figure 3 is a plan of the same.
Figure 4 is a section of the heating box detached.
Figure 5 is partly an elevation and partly a vertical transverse section on the
line A, B. Figure 2.
Figure 6 is a horizontal section on the line C, D, Figure 2.
Like letters indicate the same parts throughout the Drawing.
On a strong plate a is fixed or formed the frame b which supports the heating
box c.
The latter is formed of three separate pieces, namely, the base or bottom d,
the body e, and the cover f, as clearly shewn in Figure 4.
The mouth-piece g connected with the body is fixed thereto by means of two
pins or bolts, and is provided with a tube h, within which is placed the bulb of a
thermometer i¹. There is also a piston which enters the said mouth-piece. The
forward-and-backward motion of this piston is effected by means of the lever j,
through the medium of the screw k, which works in a female screw or nut fixed or
formed in the arın 7, movable around the axis E, F. This arm is held in its hori-
zontal position by the screw m in the support n. Another screw o, which works in
a nut fixed at the upper part of the frame b, is provided to exert strong pressure
on the cover f of the heating box c, in order to offer sufficient resistance to
the internal pressure caused by the entrance of the aforesaid plastic or other material
into the heating box, which material is forced therein by means of the piston i.
The bottom or base of the heating box c is joined to the body e by means of two
projections p, q, one of which is clearly shewn in Figure 5. The body e is provided
with four apertures r, s, t, t¹, three of which, r, s, t, may be closed outside by means
of pins or bolts passing through eyes 2, v, t, on the body e; the fourth aperture t'
communicates with the mouth-piece g. The spirit lamp a¹ serves to heat the said
heating box and the mouth-piece g.
After the above description of the said apparatus, the manner of using the same
may be easily explained.
After having removed the heating box from the frame and detached the mouth-
piece g, the cover fis raised, and the dental plate made of wax is placed in the centre
of the body c, being fixed securely therein by means of the four small wax cylinders
which pass through the apertures r, s, t, t¹. The body e having been united with the
base or bottom d; then the soft plaster or other like material is poured into the body e,
and is allowed to harden, the heating box being closed by its cover f. When the
plaster has become hard the closed heating box is placed within a receptacle filled
with water which is kept boiling. This operation causes the wax enclosed within
the plaster to melt and to rise to the surface of the water after having escaped
through the apertures 7, 8, t, t', whilst the teeth which were in the wax model or
impression remain in the plaster, which leaves uncovered those parts only that were
originally in contact with the wax. Then the mouth-piece g is attached to the
heating box, which is placed over the plate a, care being taken that the said mouth-
piece is in the proper position with regard to the piston i, so that the latter will
readily enter into and recede from the mouth-piece when the screw is turned by
means of the wheel or lever j. The screw o is then operated to exert a strong
pressure on the cover f of the heating box. Then a cylinder of the celluloid or
other plastic material to be used is placed in the mouth-piece g, the latter having
becn suitably heated. This substance or material which is pressed into the heating

page_text: box c by the piston i gradually fills the spaces left in the plaster by the melting of
the wax.
The thermometer placed in the tube indicates the temperature which should
be given to the plastic material to facilitate the introduction within the heating
box. The apertures r, s, t, serve to indicate to the operator when the spaces left by
the melting of the wax have been sufficiently filled by the plastic material. When
it is seen during the operation that the plastic material is about to escape through
one of the apertures s, t, t¹, this aperture is closed with the pin or bolt resting in
the corresponding eye to cause the material to fill up any space not yet filled. If
however the material is seen simultaneously through all three of the apertures, it is
not necessary to use the pins or bolts.
I desire to be understood that I may modify the construction of the aforesaid
apparatus or press with regard to the details of arrangement, shape, and dimensions
of the parts thereof, and the material of which they are formed to any extent which
will not impair its efficiency for the purposes of this Invention.
The chief advantages to be obtained by the use of the said Invention are as
follows, that is to say :-
By means of the above-described process and apparatus celluloid may be used for
the manufacture of dental plates in a mauner that has not been heretofore practi-
cable, for the reason that it was necessary to have recourse to existing plates,
moulds, and dimensions, whereas I am enabled to mould the celluloid to any desired
form.
The dental plates manufactured as above described are very strong, as it is
impossible for solutions of continuity to exist within the mass of caoutchouc, as is
frequently the case with dental plates manufactured by ordinary means.
Great accuracy is ensured, and the manufacture is very rapidly effected.
Having thus fully described the said Invention as communicated to me by my
foreign correspondents, and the manner of performing the same, I wish it under-
stood that I claim,-
First. The manufacture of dental plates by the process and in the manner above
described of any suitable plastic material, such as celluloid or caoutchouc, by the aid
of plaster and wax or similar materials, and in any suitable apparatus or machine,
the chief characteristic features of which process are the providing of a plaster
mould in one piece and keeping the heating box closed during the whole of the
operation.
Second. The employment of a heating box divided into two or three parts, and
the walls of which are provided with apertures, as and for the purpose above
specified.
Third. The employment of a mouth-piece and a piston of any suitable form for
introducing the plastic material into the heating box, and for causing the said
material to adapt itself to the teeth without moving them from their position, tho
said plastic material taking the place of the wax or other substance which served as
a temporary base for the dental plate.
Fourth. The apparatus or injector consisting of the parts constructed, combined,
and operating as and for the purposes above specified.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Fourteenth day of January, in the year of our Lord One
thousand eight hundred and seventy-nine.