Improvements in Fastenings for Artificial Tooth Crowns.
Year: 1899

page_text: Date of Application, 21st Oct., 1899-Accepted, 25th Nov., 1899
COMPLETE SPECIFICATION.
Improvements in Fastenings for Artificial Tooth Crowns.
I, HENRY DANIEL JUSTI, of 32nd and Spring Garden Streets, Philadelphia,
Pennsylvania, United States of America, Manufacturer, 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:-
My invention has for its object the convenient, firm and reliable connection
of an artificial tooth crown with a natural root and consists of a pin or anchor of
novel construction, whereby they may be effectively secured to each other, while
the anchor permits access to the root, when the crown is removed, without
removing said anchor from its seat in said root.
Of the accompanying drawing,
Figure 1 represents a perspective view of a fastening for an artificial tooth
crown embodying my invention, the parts being separated.
Figure 2 represents a vertical section thereof taken on line A-A Figure 4,
the parts being connected.
Figure 3 represents a top or plan view of the crown.
Figure 4 represents a horizontal section taken on line B-B Figure 2.
Figure 5 represents a perspective view of another form of my invention.
Figure 6 represents a perspective view of another part of the invention and
Figure 7 represents an end view thereof.
The same letters of reference indicate corresponding parts in the figures.
a designates an artificial tooth crown and 6 designates a vertical cavity therein.
On one of the walls of said cavity is the vertically-extending tongue c, which
projects inwardly from said wall into said cavity and is of U or V-shape in cross-
section.
d designates a pin or anchor which consists of a piece of suitable metal bent
or otherwise produced in channelled or bifurcated form with the longitudinally-
extending canal e therein, the upper end of said anchor being adapted to enter
a natural root and the lower end to enter the cavity b of the crown a it being
noticed that the canal e receives the tongue c, whereby the anchor is interlocked
with the crown through the medium of said tongue, it being further noticed
that when cement or filling material is introduced into the cavity 6, the anchor is
firmly and reliably connected with the crown and the latter may be similarly
secured to the root.
Owing to the projection of the tongue into the canal e the latter is prevented
from closing or contracting and thus loosening of the anchor in the crown is pre-
vented, it being furthermore seen that when the anchor is secured to the root, the
exposed portion or outer end of the anchor may have the crown readily fitted
to the same in a convenient manner, as the tongue and canal act as a guide for
properly fitting the crown in said end with the advantages of connecting said
parts, as has been stated.
Should it be desired to have access to the root, the crown may be displaced, and
the filling in the anchor or pin removed, when the canal of the anchor or pin
admits of the passage of the point of a desired instrument through the same to the
root or nerve thereof.

page_text: In Figure 5, the sides of the anchor or pin are corrugated or roughened as at f
to increase the holding action of the cement or filling thereon, said pin being
V-slape, while in the other figures it is U-shape, but to these features I do not
limit myself.
When desired I insert in the canal or groove e a core such as g the same being
cemented in said canal so that in case of a required operation on the root, the
crown will be removed, when access will be had to the core, the latter then being
withdrawn, leaving the canal free for the introduction of an instrument to reach
the root.
It is evident that the anchor or pin may be fused in the crown, thus firmly con-
necting the same, the other advantages stated being preserved.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:-
1st. An artificial tooth crown having a cavity therein and a tongue on a wall of
said cavity projecting thereinto.
2nd. An anchor or pin for connecting an artificial tooth crown with a natural
root consisting of a piece of metal adapted to enter said crown and root and having
a longitudinally-extending canal, the walls thereof being adapted to engage with
a projecting member in the cavity of said crown.
3rd. An artificial tooth crown having a cavity therein and an inwardly-
projecting member on a vertical wall of said cavity, and an anchor having its
ends adapted to enter respectively said crown and a natural root and provided
with a vertical channel adapted to receive said member.
4th. An anchor with a longitudinally-extending canal or groove therein for
the purpose set forth, and a core removably occupying said canal.
Dated this 21st day of October 1800
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.