Page 370 - My FlipBook

3G8 COMBINATION FILLINGS.

may be rolled between the thumb and finger into a convenient pellet
and placed entire in the cavity, pressing carefully to place with smooth
burnishers. A perfect contour may be built uj) without the aid of a
matrix.
" Tiie mixture is extremely adhesive to the dry cavity walls, and no
definite retaining shape is needed. Some of the amalgam may be saved
unmixed with the cement, and can now be burnished over the surface
of the combination filling, to which it adheres almost greedily, and thus
a pure metallic surface, like a veneer, is given it which is as durable as
an amalgam filling. Or a quick-setting amalgam may be employed
for the veneering.
" In color this combination is like amalgam, but is more granular in
appearance, and in its working properties resembles stiff cement. When
hard it takes on a metallic luster under the burnisher ; if sawed through
it shows a metallic surface. It is less soluble in the oral fluids than
oxyphosphate cement, but less durable than amalgam alone, except when
veneered with amalgam as described.
" Its advantages over amalgam are, first, its adhesiveness, which
property makes it applicable to cavities in which, for any reason, a re-
tentive form cannot be obtained ; secondly, the rapidity with which a
large cavity can be filled, a valuable item where dryness cannot be long
maintained, and making it unnecessary to employ the rubber dam in
many cases ; thirdly, the ease with which large contours may be made
without using a matrix.
" Its advantages over cement are its greater hardness and durability,
but it is less agreeable in color, hence should be employed only in the
posterior teeth."