Improvement in Artificial Dentures.
Year: 1892

page_text: Date of Application, 25th Jan., 1892
Complete Specification Left, 2nd Sept., 1892-Accepted, 15th Oct., 1892
PROVISIONAL SPECIFICATION.
Improvement in Artificial Dentures.
I, JOHN JOB STEDMAN, residing at La Porte, in the County of La Porte, State
of Indiana, United States of America, Dentist, do hereby declare the nature of my
invention for IMPROVEMENT IN ARTIFICIAL DENTURES to be as follows :-
The object of my present invention is to provide improved means whereby the
dentures shall be firmly held in place under all conditions, and this object I have
accomplished by the improvements hereinafter described and illustrated in the
accompanying drawings.
Figure is a view in side elevation of upper and lower dentures having my
invention applied thereto.
Fig. 2 is an enlarged detail view in side elevation of the casing and plunger for
enclosing the spring mechanism.
Fig. 3 is a view in vertical section through Fig. 2, the casing being shown
embedded in the ridge of the lower denture.
Fig. 4 is a view in vertical section through portions of the upper and lower
dentures showing the spring mechanism in position for use.
Fig. 5 is a detail perspective view of the spring holding rod.
Fig. 6 is a detail perspective view of the plunger.
Fig. 7 is a detail perspective view of the bearing plate for the plunger.
A and B denote respectively the upper and lower dentures, a indicating the
alveolar ridge of the upper denture, and 6 denoting the corresponding ridge of the
lower denture, these ridges being provided with teeth C. In the position usually
occupied by the last molars is placed the improved spring mechanism next to be
described. This spring mechanism comprises a casing D, the top of which is
interiorly threaded to receive a correspondingly threaded screw-cap d. This cap d
is perforated to permit the hollow plunger E to work freely therein. The hollow
plunger E is furnished at its lower end with an exterior flange e which bears against
the side walls of the casing, and gives steadiness of movement to the plunger.
Within the hollow plunger E is held a spring rod F, this rod being encircled
by the spiral spring G, which bears against the outer end of the plunger
and serves to force the same normally outward. The spring rod F serves to hold
the coiled spring G in such manner as to guard against danger of the spring
cramping, and thereby insures its uniform action. This rod F is preferably formed
with the basef which firmly seats against the bottom of the casing D. Within the
alveolar ridge a of the upper denture is embedded the edges h of the bearing
plate H, this bearing plate having a flat face to form a straight seat against which
the outer end of the plunger E will bear.
In practice, the casing D will be embedded within the alveolar ridge of the
lower denture B, in the position of the last molar of such denture and when the
dentures are in the mouth the coiled spring F will be compressed and the plunger E
will be forced inward, but the force of the spring tending to thrust outward the
plunger E will cause the dentures to be securely seated in position within the
mouth of the wearer. By providing the casing D with a detachable cap d,
the plunger, the spring and the spring rod can be removed whenever desired for
the purpose of cleaning, although it will be found that inasmuch as the plunger
works snugly within the perforated cap d of the casing there is much less danger
of the food secreting within the casing than would occur if any open joints existed
between the plunger and the casing. The cap d of the casing D, and the flange e
of the plunger E afford an accurate guide for the plunger, so that a straight.
movement thereof is insured and the spring rod within the plunger guards against

page_text: all danger of the spring becoming cramped or distorted. Consequently, while an
easy action of the plunger is secured insuring the firm seating of the dentures
within the mouth of the wearer, there is no danger of binding or cramping of the
parts in use. I have found that by providing a straight-faced bearing plate H for
the plunger, a much easier action of the dentures is secured than where a concave
plate for such purpose is used, since the straight face allows a slight lateral
movement of the plunger with respect to the plate H, thereby permitting a greater
freedom of movement of the jaws.
It will be understood that the same spring mechanism will be used upon each
side of the denture, this mechanism being located in the place of the last molars.
Dated this 25th day of January 1892.
HUGHES, SON & Co.,
38, Chancery Lane, W.C., Agents.
COMPLETE SPECIFICATION.
Improvement in Artificial Dentures.
I, JOHN JOB STEDMAN, residing at La Porte, in the County of La Porte State
of Indiana, United States of America, Dentist, do hereby declare the nature of
my 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 present invention is to provide improved means whereby the
dentures shall be firmly held in place under all conditions, and this object I have
accomplished by the improvements hereinafter described, illustrated in the
drawings accompanying my Provisional Specification, and particularly pointed out
in the claims at the end of this Specification.
Figure 1 is a view in side elevation of upper and lower dentures having my
invention applied thereto.
Fig. 2 is an enlarged detail view in side elevation of the casing and plunger for
enclosing the spring mechanism.
Fig. 3 is a view in vertical section through Fig. 2, the casing being shown
embedded in the ridge of the lower denture.
Fig. 4 is a view in vertical section through portions of the upper and lower
dentures showing the spring mechanism in. position for use.
Fig. 5 is a detail perspective view of the spring holding rod.
Fig. 6 is a detail perspective view of the plunger.
Fig. 7 is a detail perspective view of the bearing plate for the plunger.
A and B denote respectively the upper and lower dentures, a indicating the
alveolar ridge of the upper denture, and 6 denoting the corresponding ridge of the
lower denture, these ridges being provided with teeth C. In the position usually
occupied by the last molars is placed the improved spring mechanism next to be
described. This spring mechanism comprises a casing D, the top of which is
interiorily threaded to receive a correspondingly threaded screw-cap d. This cap d
is perforated to permit the hollow plunger E to work freely therein. The hollow
plunger E is furnished at its lower end with an exterior flange e which bears
against the side walls of the casing, and gives steadiness of movement to the
plunger. Within the hollow plunger E is held a spring rod F, this rod being
encircled by the spiral spring G, which bears against the outer end of the plunger
and serves to force the same normally outward. The spring rod F serves to hold
the coiled spring G in such manner as to guard against danger of the spring
cramping, and thereby insures its uniform action. This rod F is preferably formed
with the base which firmly seats against the bottom of the casing D. Within
the alveolar ridge a of the upper denture is embedded the edges h of the bearing
plate H, this bearing plate having a flat face to form a straight scat against which
the outer end of the plunger E will bear.
In practice, the casing D will be embedded within the alveolar ridge of the

page_text: e
lower denture B, in the position of the last molar of such denture and when the
dentures are in the mouth the coiled spring F will be compressed and the plunger E
will be forced inward, but the force of the spring tending to thrust outward the
plunger E will cause the dentures to be securely seated in position within the
mouth of the wearer. By providing the casing D with a detachable cap d,
the plunger, the spring and the spring rod can be removed whenever desired for the
purpose of cleansing, although it will be found that inasmuch as the plunger works
snugly within the perforated cap d of the casing there is much less danger of the
food secreting within the casing than would occur if any open joints existed
between the plunger and the casing. The cap d of the casing D, and the flange
of the plunger E afford an accurate guide for the plunger so that a straight
movement thereof is insured and the spring rod within the plunger guards against
all danger of the spring becoming cramped or distorted. Consequently, while an
easy action of the plunger is secured insuring the firm seating of the dentures
within the mouth of the wearer, there is no danger of binding or cramping of the
parts in use. I have found that by providing a straight-faced bearing plate H for
the plunger, a much easier action of the dentures is secured than where a concave
plate for such purpose is used, since the straight face allows a slight lateral
movement of the plunger with respect to the plate H, thereby permitting a greater
freedom of movement of the jaws.
It will be understood that the same spring mechanism will be used upon each
side of the denture, this mechanism being located in the place of the last molars.
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 I
claim is:
1. An artificial denture having the last molar omitted therefrom, and having
incased spring mechanism located between its plates in the position of the last
molars, substantially as described.
2. An artificial denture having spring mechanism located between its upper and
lower plates, said spring mechanism comprising a casing, a plunger within said
casing, and bearing blocks fixed to one of the plates to receive the thrust of the
plungers, substantially as described.
3. An artificial denture having spring mechanism located between its upper and
lower plates, said spring mechanism comprising a casing D, provided at its upper
end with a perforated detachable cap, a plunger working within said cap and an
encased spring within said plunger, substantially as described.
4. An artificial denture having spring mechanism located between its upper and
lower plates, said spring mechanism comprising a casing D screw-threaded at its
upper end and provided with a perforated screw-threaded cap d, a hollow
plunger E passing through said cap, and provided with a flange e, a coiled spring F,
within said plunger, and a spring rod G within said coiled spring, substantially as
described.
5. An artificial denture having spring mechanism located between its upper and
lower plates, the upper one of said dentures being provided with a straight-faced
bearing plate H, and the opposite denture being provided with a casing D having
a perforated detachable cap d, a plunger E passing through said cap and provided
with a flange e, and a coiled spring within said casing, substantially as described.
Dated this 2nd day of September A.D. 1892.
ABEL & IMRAY,
Agents for the Applicant.