Year: 1886

page_text: I, JOHN JOSEPH, RAVENSCROFT PATRICK, residing at Belleville, in the County
of Dane, and State of Wisconsin, one of the United States of America, Dentist,
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 relates to artificial teeth; & it consists in the construction and
novel combination of parts, as hereinafter described and pointed out in the claims.
Porcelain teeth as now commonly made have platinum in the form of pins or tubes
inserted in the teeth when in a soft condition or state, and the teeth are afterwards
fastened by soldering the pins with the teeth to plates of metal. The insertion of
pins in porcelain teeth tends to weaken the strength of the porcelain. To obviate
this difficulty I have made a platinum back, A, so constructed as to cover the
lingual surface, B, and surround the lateral and cervical margins, C, and, D, of
the tooth, and, in the place of inserting platinum pins into the porcelain, I cause
the porcelain to pass through one or more holes, E, which are made in the platinum
back, A, after the manner of the holes in a nutmeg grater or the like, so as to
present small, sharp, divergent points to be embraced by the clay as well as a hole
or holes for the clay to pass through by which means greater strength is given to
the body of the tooth. One of the most useful applications for which this invention
is designed is the construction of artificial crowns to be fastened to the roots of
natural teeth and when used for this purpose a platinum or gold back or lingual
surface, F, is struck up in a die prepared for that purpose, in such a manner as to
represent the natural form of the lingual surface, F, and is soldered to the
platinum back, A, on the back of the tooth. This leaves a space, H, between
the two plates of platinum. The attachment of the artificial crown, I, to the
natural root, K, is made by first fitting a band, J, around the natural root
immediately below the margin of the gum. This band, J, is then removed &
soldered to the artificial tooth crown, I, & when perfectly soldered the space, H,
is impervious to fluids, gives room for the cement and the split end of the conical
screw post, M, which forms a fixed point by means of its tapering thread in the
natural root.
This mode of attaching platinum backs to porcelain or artificial teeth, applies as
well to that class of teeth known as "plate teeth" ie. teeth that are to be soldered

page_text: to gold, platinum or silver plates. The lingual surfaces or platinum backs for the
teeth are struck up in dies, which dies embrace all the different forms of plates that
are made of gold or platinum.
The attachment of the plates is made to all of the teeth in the same manner and
the forms of the plates will vary only as the forms of teeth vary. The platinum
base of the teeth, upper and lower, extends upward on the lateral margins and is
bent into the porcelain clay at the extreme lateral points; this with the concavity
of the platinum at the base gives great strength to the tooth.
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
1. The combination with a porcelain tooth, of a platinum base having points
extending into the porcelain crown and the said platinum also extending upwards
on the lateral margins of the tooth and bent into the porcelain clay at the extreme
lateral points, substantially as specified.
2. The combination with a porcelain tooth, of a platinum base extending around
the cervical border into the body of the tooth forming a concavity at its base &
extending upward on the lateral margins of the tooth and bent into the clay at the
extreme lateral points, substantially as specified.