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184 MECHANICAL DENTISTRY AND METALLURGY.
stantly withflrawn), it will all he united perfectly. If, how-
ever, gold plate has l)een used entirely in forming the crown-
FiG. 159. plate, a small piece of solder wi )e
needed to unite them.
The crowai is now ready for the finish-
ing- processes, which consist in filing or
grinding off any projecting edges of the
cusp-piece flush \vith the face of the
crown, and smoothing and heveling the
free edge of the hand or ferrule; the
crown should then he adjusted to the root
and the occlusion noted. If, as is fre-
quently the case, a little of the gold needs
to be removed at one or more points, in
order to have a perfect occlusion, it should
be done with a small, flat-faced carbo-
rundum-stone. The crown should then
be removed and polished at the lathe.
Another method is to take a wax or modeling compound
impression of the root w^th three or four of the adjoining
teeth, and also of the antagonizing teeth. Secure casts of
the same; outline the root to be crowned, clearly on the
model and from this secure a metal die. The band is fitted
to this die and transferred to the articulated plaster model
for contour and final adjustment.

BRIDGE-WORK.
As w-e have previously written upon this subject (see
Richardson's Mechanical Dentistry), bridge-work, to the
skilled dentist with experience in crown-work, does not
present any great difficulty, inasmuch as crowns are the
beginning and the end; it is practically continuous crown-
work, though many of the crowns—those filling or bridging