Improvements in Artificial Teeth.
Year: 1890

page_text: Date of Application, 19th July, 1890-Accepted, 23rd Aug., 1850
OMPLETE SPECIFICATION.
Improvements in Artificial Teeth.
1, JOHN SMALLEY CAMPBELL, of 10 Park Square West, Regent's Park, in the
County of Middlesex, Engineer do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
The object of my invention is to improve the construction of an artificial or
porcelain tooth, so that it may be more firmly attached to the mouth plate by
soldiering, and thus improve that style of work called by the dental profession
"metallic plate work with soldered backings," that it may have upon the lingual
side a more natural contour and feeling to the tongue of the wearer, and that it
may be more easily cleaned by brushing or washing than ordinary artificial teeth
can be. My invention also affords an improved means of attaching artificial crowns.
to natural roots.
In the accompanying sheet of drawings
Fig. 1 is a perspective view of a metallic mouth plate, having artificial teeth affixed
to it in accordance with my invention.
Fig. 2 is a perspective view of a single tooth constructed according to my invention,
with a narrow vertical slot in its lingual side, and a thin narrow platinum plate
secured in the bottom of the slot.
Fig. 3 is a horizontal section of Fig. 2, viewed from the base of the tooth
and shewing a metal pin crossing the vertical slot and embedded in the tooth
structure.
Fig. 4 is a perspective view of a single tooth, made in accordance with my invention,
with a narrow vertical slot in its lingual side, said slot being widest at the bottom,
and narrowest at the lingual side of the tooth, and having a thin narrow piece of
platinum at the bottom of the slot.
Fig. is a horizontal section of the tooth shewn in Fig. 4.
Fig. 6 is a perspective view of a single tooth made in accordance with my
invention, with a vertical slot in the lingual side, a platinum tube beginning at each
side of the slot and passing through the tooth and having a thin narrow strip of
platinum at the bottom of the slot, the two tubes and the said strip being all made
of one piece of platinum as shewn in Figs. 14 and 15.
Fig. 7 is a horizontal section of the tooth shewn in Fig. 6.
Figs. 8 and 9 are respectively a perspective view and horizontal section of a tooth,
constructed in accordance with my invention with a vertical slot in the lingual side,
a platinum tube beginning at each side of the slot in the tooth and terminating in
the tooth structure, and a thin platinum bottom to the slot, the platinum bottom and
the two tubes being all made of one piece of platinum as shewn in Figs. 14 and 15.
Fig. 9 shews a platinum mandrel bent as it may be after the tooth has been baked,
as will be hereinafter described.
In Figs. 4 and 5 the vertical slots are shewn as narrowest on the lingual side
of the tooth. In Figs. 2, 3, 6, 7, 8 and 9, they are shewn as widest on the
lingual side.
Fig. 10 is a view of the crown of a tooth made in accordance with my invention,
and provided with a gold band and a pin for insertion in the cavity of a. root, and ao
bar or wire passing through the tube, to be attached.to a natural tooth by gold
fittings, or to other artificial crowns, as shewn in Fig. 13.
Fig. 11 is a horizontal section of the tooth shewn in Fig. 10, exhibiting a horizontal
tube with a mandril in it, extending through the tooth crown.
Fig. 12 exhibits a root with a crown, like that shown in Figs. 10 and 11 *secured
to it, except that the tube does not extend entirely through the tooth.

page_text: Fig. 13 shows a tooth similar to that shown in Fig. 12, with a tooth crown impaled
on a horizontal mandril, showing how one tooth root may be utilised to support two
tooth crowns.
Fig. 14 is a view of a piece of thin platinum plate, forming a blank, which may
be employed to form a tube, open where it crosses the slot, and forming the platinum
bottom to the slot, such as shewn in Fig. 15 all to be imbedded and baked in with
the tooth, as shewn in Figs. 6, 7, 8, and 9, and adapted to receive a mandril extending
across the vertical slot in the tooth.
'
Fig. 16 is a perspective view of a single tooth, made in accordance with my
invention, having a single vertical tapered slot, broadest at the base and formed in
the lingual side of the tooth, with a piece of platinum fitting same slot and burned
or baked therein.
Fig. 17 is a perspective view of a piece of hard platinum plate alapted to fill
the slot in the tooth, shewn in Fig. 16, and which is moulded and baked with
the tooth.
Fig. 18 is a perspective view of a porcelain tooth constructed according to my
invention with a narrow vertical slot in its lingual side, widest at the bottom and
having no platinum or metal whatsoever used in its construction.
Fig. 19 is a perspective view, showing the ordinary way of attaching porcelain
teeth to a gold plate.
Similar letters of reference denote similar parts throughout the drawings.
In Fig. 1. A represents a metal dental plate, and B, teeth secured thereto, in
accordance with my invention.
C'in Figs. 2 and 3 represents a tooth detached and provided with a vertical narrow
slot D, preferably tapered or wedge shaped, with its widest part at E, on the lingual
side of the tooth. This slot should extend to about the centre of the tooth, and is so
narrow that it does not materially impair the strength of the tooth. Its object is to
receive a thin metallic vertical plate or backing, soldered or otherwise firmly
connected to the plate A, so that the said plate or backing will be substantially at
right angles to the said plate, or the slot may be entirely filled with solder, without
fitting any other backing material.
F, Fig. 3 indicates a pin of platinum extending across the vertical slot D, with its.
ends supported in the tooth structure. This pin is moulded into place in the process
of forming the tooth by means of formers or moulds as well understood in the art of
manufacturing porcelain teeth.
In the tooth shown in Figs. 2 and 3, I place at the bottom of the slot a thin
platinum strip H. The object of the said strip being to carry or attract the solder to
the bottom of the slot, thus ensuring a complete and solid filling of the slot with
solder or meal and so ensuring a perfect soldering of the tooth to the mouth plate A,
and forming what is called the backing of the tooth. Such backing will consist as
shewn at 1, of a thin vertical plate of metal, filling the slot in each tooth, and
standing in the slot at about right angles with the edge of the plate, where the
tooth is set.
Fig. 14 represents a piece of platinum plate, slit as indicated by the lines a a a a,
the four corners are then rolled up on a inandril to form two tubes bb, the finished
appearance of the piece being shewn by the perspective view Fig. 15. The ends H
forming the platinum strip are placed in the bottom of the slot D. Tuo tubes being
moulded into the structure of the tooth, as shewn in Figs. 6, 7, 8, 9, 10, 11, and 13.
In Figs. 6, 7, 10, 11, and 13 the tubes extend through to the outside of the tooth
structure, but in Figs. 8 and 9 the tubes are shorter and end within the structure
of the tooth. A platinum wire c loosely filling the tubular ends bb may be place!
in position, as shewn in Fig. 9, and after the tooth has been baked, this wire may
bu bent out into the slot D by passing a small smooth instrument between it and
the platinum plate at the bottom of the slot; the appearance of the pin after being
so bent is shewn in Fig. 9. The object of this pin is to make a firmer attachment
for the rubber or solder filling; this pin being surrounded by the tubes bb, is not
bake into the tooth and may be subsequently removed, if desire. I prefer however.

page_text: to allow it to remain, as it serves to carry the solder into the tubular ends and so
prevent contraction in soldering.
By making the vortical slot D widest at the bottom, as shewn in Figs. 4 and 5,
and using a simple piece of thin platinum at the bottom of the slot a tooth may be
used without any tube or pin crossing the slot, in this case the tooth can be easily
moulded by drawing the piece forming the slot from the bottom in the direction
of the line S. T. from T. to S.
When the tubes bb pass to the proximal sides of the tooth, as shewn in Figs. 6, 7,
10, 11, and 13, the tooth after being mounted upon a natural root by the ordinary
gold band may be made to carry another artificial crown by means of a mandril K,
as shown in Fig. 13. The object of leaving the tubes open in the centre is to allow
the solder to pass from the slot into the tubes, or to allow the rubber, aluminium
celluloid, or any cast plate material, to enter the tubes, when such materials are used.
In Figs. 16 and 17 the tooth C is formed with a slot D, widest at the bottom, and
the wedge shaped platinum plate L of the same form as the slot, is baked therein. This
plate should be roughened upon its sides to engage with the tooth structure and thus
prevent its coming out. This tooth will require no fitting of a backing, as in ordinary
plate teeth, and has the advantage of presenting the platinum edgewise to receive
the strain incident to use of the teeth in mastication.
The tooth shewn in Fig. 18, bas the advantage that it is the cheapest to manufacture
and can be used for all plastic work, and for cast plates of aluminium and other
fusible metals used in cast plate work. A further advantage of this form of tooth is,
that should it be desired to solder it to a swaged or other metal plate, it will only
be necessary to slip a thin piece of platinum in the bottom of the slot and fix it
therein, by a burnishing or other suitable instrument.
In some cases if desired the tubes bb may be separate from the strip H, or a single
separate tube may be used, as shown in Fig. 11.
According to the usual method of fastening porcelain teeth to a metallic plate, the
gold backing is fastened flatwise to the plate and is fixed on the lingual side of the
teeth by platinum pins dd, Fig. 19, projecting from each tooth. The result is that
the backing is substantially a thin flat extension of the plate upon the lingual side of
the tooth. As the strain upon the tooth in use is forward and backward, or in the
direction of the outer and inner faces of the tooth, it will be perceived that by the
ordinary method, the backing is applied in such relation to the tooth and plate as to
present the least resistance to bending or displacement of the teeth. As the proximal
sides of the teeth are in contact the teeth are self-supporting in that direction.
Besides very little strain occurs in the direction of the row of teeth, it being ordinarily
across the row. The attachment of artificial teeth to a metallic plate by the old
method is therefore weak and insecure, and insufficient to resist the only strain they
are liable to incur. Besides this, another objection to the old method is, that it
gives an unnatural and unpleasant feeling when the tongue of the wearer comes in
contact with the lingual sides of the teeth. A further and still greater objection is,
that the ordinary backing usually covers not only the lingual sides of the teeth but
also the lower parts of the spaces between the teeth upon the lingual sides, thus
making it very difficult to cleanse them. Consequently matter accumulates between
the teeth on the lingual side, around and under the edges of the backing, and becomes
offensive, and it is difficult, if not impossible, for the wearer to dislodge it. By
my improvements a thin plate, of suitable material to form a backing for each tooth,
is set into the teeth so that the strain is always edgeways and never sideways upon
the backing. 1 thus secure the greatest strength possible in a tooth backing, and
at the same time I reduce the quantity of material used in the backing to the
minimum. Besides this I preserve a natural contour on the lingual side of each tooth
and avoid exposing any edges of the backing, around and behind which it is possible
for matter to accumulate and become foul and offensive.
Porcelain teeth constructed according to my invention are practically universal
teeth, as they can be fixed to any description of plate work, or to natural roots, and

page_text: can be used in any kind of crown or bridge work; the security of attachment and
the comfort to the wearer being greater than in any system heretofore in use.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what T
claim is :-
1. A. porcelain tooth provided on its lingual side with a narrow vertical slot
adapted to receive a thin backing to connect the tooth with the plate, which backing
has its edges substantially at right angles with the edge of the plate where it is
applied, substantially as described.
2. A porcelain tooth provided on its lingual side with a narrow vertical slot
adapted to receive a thin backing to connect the tooth with a plate, which backing
has its edges substantially at right angles with the edge of the plate, where it is
applied, in combination with a pin crossing said slot and having its opposite ends
bearing in the tooth structure, substantially as set forth.
3. A porcelain tooth provided with a vertical slot in its lingual side, and a
platinum plate or wire secured in the bottom of the slot, substantially as set forth.
4. A porcelain tooth provided with a vertical slot in its lingual side and a tube
crossing the slot, substantially as set forth.
5. A porcelain tooth provided with a vertical slot in its lingual side, a platinum
plato in the bottom of the slot, and a tube crossing the slot, substantially as
set forth.
6. A porcelain tooth with a vertical slot in its lingual side, a platinum bottom to
the slot and two small tubes extending from the sides of the slot into the tooth
structure, substantially as set forth.
7. A porcelain tooth having a vertical slot in its lingual side with one continuous
piece of platinum forming or covering the bottom of the slot, and the two cylindrical
ends baked into the tooth structure, substantially as described.
'
8. A porcelain tooth having a vertical slot in its lingual side with one continuous
piece of platinum forming or covering the bottom of the slot and the two cylindrical
ends baked into the tooth structure and passing entirely through from the sides of
the slot to the proximal sides of the tooth, substantially as described.
9. A porcelain tooth with a vertical slot in its lingual side, a platinum bottom to
the slot, two tubular ends extending from the sides of the slot, into the tooth structure
on both sides of the slot, and a loose platinum pin or wire crossing the slot and
reaching into the tubular projection on both sides of the slot, substantially as
described.
10. A porcelain tooth with a slot in its lingual side, a platinum bottom to the slot,
and a platinum pin crossing the slot and baked into the tooth structure in both sides
of the slot, substantially as described.
11. A porcelain tooth baving a vertical slot in the lingual side filled with a strong
platinum plate baked in the slot, substantially as set forth.
Dated this 19th day of July 1890.
AMBROSE MYALL,
21, Cockspur Street, S.W., Agent for the Applicant.