Page 164 - My FlipBook

160 FILLING TEETH.

of the advantages of this method over that just
described, are the following: the rilling can be intro-
duced far more rapidly ; and the laminae, or leaves of
foil, take a more perfect position in the cavity, and
consequently the structure of the rilling is better.
The form of the cavity should be much the same as
that for any other method of rilling; there should be
some retaining point so situated that the first block,
or blocks, can be fixed firmly in place, so that there

will be no liability of loosening during the subsequent
part of the process. It is important to have such an
arrangement, as otherwise it would be necessary to
employ an instrument in the left hand to retain the
first blocks in situation, till enough were introduced
to bind the whole by pressure upon two opposite
points in the cavity.
Forming Blocks.—For forming blocks, use any

number of foil that may be desired, usually No. 4 or
6, and either lay four to six sheets together, or fold a
single sheet into that number of thicknesses; then
cut off, from the sheets thus prepared, strips about
one-third to one-fourth wider than the depth of the
cavity to be rilled; which are then rolled on a
small three or four-sided broach—the three-sided is
better; this instrument should be very small; no
larger, indeed, than is necessary for strength. Its
sides should be perfectly smooth, and its angles