Page 91 - My FlipBook

GOLD AND OXYPHOSPHATE.
77
the damage done by the operator. She, with her wonderful intelli-
gence, at once begins a deposition of lime-salts against the surface of
the gold. The tubuli thicken as to their walls, so that their contents
and consequently their power to transmit impressions diminish. So
much for the physiology of the condition. Let us now consider the
treatment. It is to smear the dentine with oxyphosphate, and while
this is still plastic, and of sticky consistency, crowd in two or three well-
annealed pellets of gold. In large cavities crystal is better. The
phosphate must now be left to set thoroughly. Then the gold may
be compressed, and will be practically cemented into place. This aids
in its retention, but should not be to the exclusion the
depended ^^pon of
usual methods of shaping the cavity. The next step is to carefully
scrape off all oxyphosphate which reaches or covers the margins.
The filling may then be completed with any gold. It will be claimed
that even is a conductor of heat.
oxyphosphate good This is true,
but it is less so than Besides, the of a material
gold. conductivity
depends upon its homogeneity. The fact that a filling of this char-
acter is composed of two masses, gold and oxyphosphate, renders the
whole a poorer conductor than if it were made of either exclusively.
Beginning, then, from the point of using this method in sensitive
teeth, we quickly determine to employ it in cases where the pulp is
really nearly approached. Here a greater mass of oxyphosphate may
be used. When we have become dexterous in the operation in these
two classes of teeth, we soon begin to wonder why it is not applicable
in those large or deep cavities of retentive shape, but where we find it
difficult to obtain a starting-point. At once we see the advantage of
using the phosphate for cementing in the first pieces, merely to start a
filling. As it is perfectly feasible, is it not more sensible than to drill
a or bur out an extra groove ? So that having passed through
pit,
all the phases, beginning with ridiculing the method, I have almost
reached the point where I use it exclusively. Where I do not employ
it is mainly in cavities which are quite small, or where the immediate
circumstances seem to make it less convenient or advisable than to
depend upon gold alone. It is a habit that will grow upon a dentist,
and the result upon the patients in his practice will be a lessening of
the number of those reports about teeth being sensitive after filling.
Of course there are some teeth which will be responsive to hot and
cold, even after this has been done. Then the dentist may be com-
forted with the thought that it would have been worse if gold alone
had been used. Indeed, the pulp would most probably have died.
Gold and Platinum. This is a preparation furnished by some
manufacturers. The exact proportions of the two metals I do not
know, but there is enough of the platinum to materially affect the
color of the finished filling, though during the operation there will be