Page 558 - My FlipBook

266 THE TECHNICAL PROCEDURES IN FILLING TEETH.

if not, add more before making complete condensation.
oughly ;
When this is done, pack a mass of gold on the first, filling the
angle somewhat as shown in Figure 343. If the convenience
point has been properly made, the gold built in will stay in place.
Remember that if the bottom of the convenience point is round,
as made with a round bur, this tirst piece of gold will roll and be
loose ; but if the bottom is well sipiared, and the angles with the
walls are sharp, as made with an inverted cone bur, this tirst
piece of gold will remain firm. Then the bucco-axio-gingival
angle may be tilled in the same way. This, howevei', calls for a
change to a partial cross mouth position, something similar to
those shown in Figures 59 and 61 (finger positions) which is
usually easy enough to attain if the mouth is opened widely.
Sometimes it may be found necessary to do this with a contra-
angled instrument. AVhen the gold has been packed into this
angle also, the 5-10-3 or 7i/o-10-3 should generally be changed
for the parallelogram plugger 6x12-5-10, Figures 324, 344, for
building across from one point angle to the other along the axio-
gingival line angle as shown in Figure 345. Sometimes it may
be preferred to build along this angle to the bucco-axio-gingival
angle before filling this latter convenience point, keeping the
holding instrument in position on the gold while so doing. Then
the immediate angle is filled, as before described. The choice
in these plans will be purely a matter of convenience in the
particular case.
The angle at which the condensing force is applied
toward the plane of the wall is very important in making per-
fect adaptation. The directicm of force should never be per]ien-
dicular to the plane of the wall that is being covered. Whenever
possible, the angle of force should be inclined as much as twelve
centigrades from the perpendicular to the plane of the wall.
In adapting gold to the surrounding walls in an occlusal cavity,
or to the buccal and lingual walls of a proximo-occlusal cavity,
the direction of force should be inclined toward the wall, if pos-
sible, as much as six centigrades. It is quite possible, however,
by using the wedging principle, to secure good adaptation if the
angle of force is parallel with the wall.
The wedging principle. The stepping of the plugger should
always be from the central part of the mass of gold toward the
walls, and the last condensation of each individual piece of gold
added should be along the wall being covered.
This rule is practically universal to filling with cohesive
gold, except when condensing a piece laid upon central parts