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132 OPERATIVE DENTISTRY

in the way of covering the pulpal wall till the gold in the cavity por-
tion has reached a level with the axio-pulpal line angle.
The Contact Point. The bviilding of contact point should receive
special attention when the proper height of the filling has been
reached. The gold should be thoroughly condensed against the prox-
imating tooth much in the same manner as it is wedged against the
walls, and should receive extra malleting to insure extreme hard-
ness.
Position of Contact Point. When the proximating tooth is in-
tact, the contact point should be in about the same position as it
was previous to decay, and should be a contacting point and not sur-
face or a line of contact. This should round away from this point

Fig. 76.— Starting cohesive gold, third plan.
in much the same manner as do the surfaces of two marbles when
touching, and has come to be spoken of as the "marble contact."
(See Fig. 26.)
Moving Contact Point Flush to Occlusal. The contact point
should be moved occlusally when both promixating surfaces are to
be restored, one a mesial and the other a distal filling in the teeth
making up the proximal space being considered, and when there has
been considerable occlusal wear. This will result in a contact point
from which the surfaces round away in all directions except toward
the occlusal surface and is known as the "half marble contact" ad-
vised for the above condition only. In this connection attention is
called to the immunity to decay of proximating surfaces where the
"half marble contact" has been produced by occlusal wear. Many
instances are seen where caries already started in such spaces have