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ARTIFICIAL DENTURES. 8 I

wliicli liaxe ])een pre\-i<>usly cut from llic model, as sliown in
Fig". 46. "1^10 outlines of the pattern are then traced upt^i
the plate of gold or other metal used for the base. The
redundant portions of plate are then cut away with plate
shears and forceps, and the edges trimmed smooth with a
file. A very convenient and almost indispensable instru-
ment for cutting away the plate in conformity with the
palatal curvatures of the teeth is the plate forceps, exhibited
in Fig. 47.
Swaging the Plates.—The plate cut to the proper form
is now annealed, then placed upon the die, and if for a full
upper denture, or in a partial where the plate is to extend
over the alveolar ridge, it is brought as nearly as possible
into adaptation Avith No. i of the " progressive counter-
FiG. 47.

dies."'* To form this narrow counter die the sand must be
built entirely over the ridge, allowing only the palatine
portion of the die to be exposed. The swaging process is
continued by using counter dies Nos. 2 and 3. The second,
as will be noted in Fig. 49, extends just beyond the center
of the ridge, to gradually start the plate over the ridge,
while the third or final counter, Fig. 50, embraces the
entire ridge in the usual manner. The two metallic pieces
—that is, the die and counter-die—are brought forcibly
* First described by Prof. I. N. Broomell.