Improvements in Artificial Dentures.
Year: 1895

page_text: Date of Application, 17th Sept., 1895-Accepted, 26th Oct., 1895
COMI LEIE
Improvements in Artificial Dentures.
We, GEORGE ADISON JOHNSTON, and HOUSTON MONROE CARROLL, of San
Antonio, in the County of Bexar, and State of Texas, United States of America,
Gentlemen, 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 :---
This invention relates to artificial dentures, and particularly to lower sets, and
aims to provide retainers and combine them with the plate so as to hold the
denture in place against accidental displacement during the process of articulation,
prehension, mastication and deglutition.
Dentures of this character have been provided with clasps to engage with the
jaws, the alveolar process or gums and have been found objectionable because of
the discomfort attendant upon their wearing and because the clasps do not give
satisfactory results. The present invention provides retainers which fill a vacuum
in the mouth never heretofore utilized in the construction of artificial teeth, and
which form a rest for the muscles in their contraction incident to the movements
of the jaws, and these retainers render a lower set of artificial teeth as comfortable
and serviceable as if they were natural.
The improvement consists of the novel features which hereinafter will be more
fully set forth and claimed, and which are shown in the accompanying drawings,
in which:
Figure 1 is a perspective view of a lower set of artificial teeth showing the
application of the invention.
Fig. 2 is a side elevation.
Fig. 3 is a rear view thereof.
Fig. 4 is a detail view of a retainer.
Figs. 5 and 6 show, respectively, the obverse and reverse of a modified form of
retainer.
The numeral designates a plate for a lower set of artificial teeth, and 2 the
teeth attached thereto, and this plate 1 may be of any desired pattern common in
the construction of lower dentures. The retainers 3 may be made of any suitable
material, either metal or a plastic composition, and are separate and independent of
the plate and are attached thereto in any convenient manner, and may be attached
to either side of the plate according to the convenience of the wearer.
These retainers comprise a curved shank portion 4 by means of which the
retainers are attached to the plate, and an expanded portion 5 the latter curving
upwardly and outwardly and convexed on the side designed to come opposite to
the cheek. The expanded portion 5 is concaved on its inuer side to conform to
the convexity of the outer side, thereby attaining a light structure, and this
expanded portion 5 is partially twisted at 6, and inclines outwardly and sets at
an angle to the shank 4 so as to conform to the shape of the mouth and secure
ease and comfort to the wearer.
When the retainers are properly positioned the expanded portions 5 project
vertically from the rear ends of the plate and serve to secure the latter in
position and prevent tipping and loosening thereof during the several movements
of the jaws.
The retainer may be wide at the point of juncture of the upwardly-extending
portion 5 with the shank 4 as shown most clearly in Figures 2 and 4, or the said

page_text: In
juncture may be contracted to form a comparatively small neck portion as shown
in Figs. 5 and 6 the latter construction being preferred in some instances.
every case, the expanded portion 5 will be concavo-convex so as to attain the
best possible results in the accurate and proper fitting of the denture within the
mouth.
The invention is readily adapted for dentures now in use as well as those to be
constructed, and in adapting the same to the particular requirement it is to be
understood that changes in the form, proportion and the minor details of construc-
tion may be resorted to without departing from the principle or sacrificing any of
the advantages of this invention.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. In an artificial denture, a lower plate having retainers extending vertically
from its inner or rear ends and above the plane of the biting edge of the teeth,
substantially as described for the purpose set forth.
2. The combination with a lower set of artificial teeth, of retainers secured to
the inner ends of the plate and having vertically-extending portions which are
concavo-convex, and which occur at oppositely extending angles, substantially as
set forth.
3. The combination with a lower set of artificial teeth, of retainers having
curved shank portions which are attached to the inner ends of the plate and
having expanded portions which extend vertically and are concavo-convex said
expanded portions standing at opposite angles, substantially as set forth for the
purpose described.
Dated this 17th day of September 1895.
WHEATLEY & MACKENZIE,
40 Chaucery Lane, London, W.C., Agents.