IMPROVEMENTS IN DENTAL APPLIANCES
Year: 1877

page_text: LETTERS PATENT to Robert Marston, of Leicester, in the County of Leicester,
Dentist, for the Invention of "IMPROVEMENTS IN DENTAL APPLIANCES."
Sooled the 17th January 1878 and dated the 18th July 1877.
PROVISIONAL SPECIFICATION left by the said Robert Marston at the Office
of the Commissioners of Patents on the 18th July 1877.
ROBERT MARSTON, of Leicester, in the County of Leicester, Dentist.
MENTS IN DENTAL APPLIANCES.'
"
"IMPROVE-
I employ a valve constructed as follows:-Each valve is round in plan but of a
half oval shape, or of a shape approaching thereto, in section, and is flanged. At
the greatest diameter from the flange project two or more wings or tabs. The basin
of the valve is pierced with a series of holes near the flange, and from the centre of
the basin a screwed pin projects. This pin is provided with a circular nut, having
a nick across its diameter to admit of its being screwed in place by a forked key.
The nut being unscrewed a flexible centre of india-rubber or other equivalent
material, having a small hole in its centre, is placed upon the screwed pin in the
basin of the valve. The nut being then put on and screwed home the valve is ready
for use.
Valves so constructed may have the basins made of gold, platina, dental alloy,
and other metals or materials, and are applicable to the upper and lower partial
or entire dentures, and in appliances employed in treating deformities of the palate.
A dental plate or other appliance supplied with a valve constructed as above
described enables the user to suck out the air and form a vacuum, which causes the
plate or other appliance to adhere to the roof or other portion of the mouth.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Robert Marston in the Great Seal Patent Office on the 12th
January 1878.
ROBERT MARSTON, of Leicester, in the County of Leicester, Dentist.
MENTS IN DENTAL APPLIANCES."
"IMPROVE-
I employ a valve constructed as follows:-Each valve is round in plan but of an
half oval shape, or of a shape approaching thereto, in section, and is flanged at the
greatest diameter. From the flange project two or more wings or tabs. The basin
of the valve is pierced with a series of holes near the flange, and from the centre of
the basin a screwed pin projects. This pin is provided with a circular nut, having
a nick across its diameter to admit of its being screwed in place by a forked key.
The nut being unscrewed a flexible centre of india-rubber or other equivalent
material, having a small hole in its centre, is placed upon the screwed pin in the
basin of the valve. The nut being then put on and screwed home the valve is ready
for usc.
Valves so constructed may have the basins made of gold, platina, dental alloy,
and other metals or materials, and are applicable to the upper and lower partial or
entire dentures, and in appliances employed in treating deformities of the palate.
A dental plate or other appliance supplied with a valve constructed as above
described enables the user to suck out the air and form a vacuum, which causes the
plate or other appliance to adhere to the roof or other portion of the mouth.
Figures 1, 2, and 3 represent respectively a lower, sectional, and upper side views
of an upper denture, provided with my improved valve.
Figures 4 and 5, an upper and lower view of a lower denture with my improve-
ments attached thereto.
And Figures 6 to 10 shew enlarged views of separate portions of my improved
valve, severally referred to hereafter.
I construct each valve as follows:-The shell A, shewn at Figures 6, 7, and 8, is
round in plan but of an half oval shape, or of a shape approaching thereto, in
section, and is flanged at the greatest diameter, and when required two or more
wings or tabs project from the flange. The basin of the valve is pierced with a
series of holes near the flange, shewn at Figure 7, and from the centre of the basin
a screwed pin projects. This pin is provided with a circular nut B, seen at Figures
6 and 8. The nut has a nick across its diameter to admit of its being screwed in
place by a forked key. The nut being unscrewed a flexible centre of india-rubber C,
shewn at Figure 9, or other equivalent material, having a small hole in its centre,
is placed upon the pin in the basin of the valve. The nut being then put on and
screwed home the valve is ready for use.
Valves so constructed may have the basins made of gold, platina, dental alloy,
and other metals or materials.
A valve so constructed embodied in an upper denture, on the concave or lingual
surface, is shewn at Figure 1. The under side of the valve is held to the base plate,
if of gold or other metal, by solder fused along its outer edge; if of vulcanite or
similar material, by such material overlapping the bevelled edges of the valve.
In some cases the wings of the valve may be slightly bent upwards and be buried
in the base.
The recess shewn at Figures 2 and 3, surrounding the valve A in the base plate,
enables a vacuum to be formed when in use by a patient. This recess instead of
being formed across the upper denture may be formed in the direction of the length
of the base plate. In such recess I sometimes place a perforated gate (shewn
separately in plan at Figure 10), of metal, or vulcanite, or similar material, in the

page_text: recess on the top of the upper denture, to prevent the palate of the user from contact
with the valve; this gate likewise ensures a better vacuum.
The valves for the lower denture, upper and lower views of which are shewn
respectively at Figures 4 and 5, differ from the one first described in not having
wings; and it is likewise provided with a mastication cap or plate A', of the shape
shewn in plan at Figure 4. This cap or plate is either soldered or rivetted to or
forms part of the nut above named, and when screwed up the edges, which are
roughened, rest upon the base, thus enabling it to resist pressure when used in
masticating without injuring the screw of the valve, and yet prevents food from
clogging the perforations of the valve. There is one such valve mounted on each
side of the denture, as shown at Figure 4; one shewn without the cap nut at A,
and another with the cap nut in position at A', Figure 4. The shape of the recesses
on the lower side of the denture are shewn at Figure 5.
Valves constructed and mounted as above described are shewn in the Drawings
as applied only to an upper and lower denture, but they are equally applicable to
partial dentures and appliances employed in treating cleft palates and other
deformities of the palates.
A dental plate or other appliance supplied with a valve constructed as above
described, enables the user to suck out the air and form a vacuum, which causes the
plate or other appliance to adhere to the roof or other portion of the mouth.
•
Having thus fully described the nature of my said Invention, and the manner of
performing the same, I wish it understood that I claim for the construction and
employment of a dental valve or valves, substantially as herein-before described,
and illustrated in the Drawings annexed.
In witness whereof, I, the said Robert Marston, have hereunto set my hand
and seal, this Eleventh day of January, in the year of our Lord One thousand
eight hundred and seventy-eight.
Witness,
H. W. GOUGH, C.E.,
Nottingham.
ROBERT MARSTON. (LS.)