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OXYSULFATE OF ZINC. 343
Plugs of softened temporary stopping have been used for the arrest
of alveolar hemorrhage ; also for the temporary setting of artificial
crowns.
Lining Varnishes.
These are solutions of various gums and resins in alcohol, chloro-
form, and ether, which are employed to furnish a non-conducting and
impermeable film to cover the dentinal w'alls of excavated cavities.
The first, sandarac varnish, is a thin solution of sandarac in alcohol.
The second, a solution of virgin rubber in chloroform.
The third a solution of hard Canada balsam, copal, or damar in
ether.
Another is the preparation known as I'ristaline, a solution of trinitro-
cellulose in anhydrous amyl acetate.
Before lining a cavity with zinc oxychlorid, a film of one of these
varnishes, the quick-drying ones preferred, is applied, and when this is
dry the cement may be inserted without causing pain. Varnishes have
been used to furnish an adhesive surface upon which to pack gutta-
percha fillings. It is always advisable to varnish the walls of a cavity
which is to receive a filling of zinc phosphate, to prevent the action of
any free acid or acid salt upon the dentinal walls.
Some of these varnishes are admirable non-conductors, and serve
in that capacity under gold or amalgam fillings in a most satisfactory
manner.
They may be used to prevent the tooth discoloration due to the pres-
ence of amalgam, particularly of copper amalgam.
OxYSULFATE OF ZiNC.
What is known as the oxysulfate of zinc in dental parlance is
merely a thin zinc oxychlorid containing zinc sulfate. A true zinc
oxysulfate is made by mixing a saturated solution of zinc sulfate wdth
uncalcined zinc oxid. It forms a white paste which sets quickly and
attains about the hardness of an inferior plaster-of-Paris.
It is bland and unirritating to exposed pulps ; is a non-conductor
is faintly and persistently astringent.^
Its principal use is as a pulp capping or protective. A thin paste is
made, in which a disk of paper is dipped, then quickly and accurately
laid upon the area of exposure. When hard (in a few seconds) a drop
of fresh thin paste is flowed over the capping. The cavity may then be
lined with zinc phosphate.
As a pulp protector from thermal shock it is applied in a thin layer,
and over it a lining of zinc phosphate is packed.
^ J. Foster Fiagg.
OXYSULFATE OF ZINC. 343
Plugs of softened temporary stopping have been used for the arrest
of alveolar hemorrhage ; also for the temporary setting of artificial
crowns.
Lining Varnishes.
These are solutions of various gums and resins in alcohol, chloro-
form, and ether, which are employed to furnish a non-conducting and
impermeable film to cover the dentinal w'alls of excavated cavities.
The first, sandarac varnish, is a thin solution of sandarac in alcohol.
The second, a solution of virgin rubber in chloroform.
The third a solution of hard Canada balsam, copal, or damar in
ether.
Another is the preparation known as I'ristaline, a solution of trinitro-
cellulose in anhydrous amyl acetate.
Before lining a cavity with zinc oxychlorid, a film of one of these
varnishes, the quick-drying ones preferred, is applied, and when this is
dry the cement may be inserted without causing pain. Varnishes have
been used to furnish an adhesive surface upon which to pack gutta-
percha fillings. It is always advisable to varnish the walls of a cavity
which is to receive a filling of zinc phosphate, to prevent the action of
any free acid or acid salt upon the dentinal walls.
Some of these varnishes are admirable non-conductors, and serve
in that capacity under gold or amalgam fillings in a most satisfactory
manner.
They may be used to prevent the tooth discoloration due to the pres-
ence of amalgam, particularly of copper amalgam.
OxYSULFATE OF ZiNC.
What is known as the oxysulfate of zinc in dental parlance is
merely a thin zinc oxychlorid containing zinc sulfate. A true zinc
oxysulfate is made by mixing a saturated solution of zinc sulfate wdth
uncalcined zinc oxid. It forms a white paste which sets quickly and
attains about the hardness of an inferior plaster-of-Paris.
It is bland and unirritating to exposed pulps ; is a non-conductor
is faintly and persistently astringent.^
Its principal use is as a pulp capping or protective. A thin paste is
made, in which a disk of paper is dipped, then quickly and accurately
laid upon the area of exposure. When hard (in a few seconds) a drop
of fresh thin paste is flowed over the capping. The cavity may then be
lined with zinc phosphate.
As a pulp protector from thermal shock it is applied in a thin layer,
and over it a lining of zinc phosphate is packed.
^ J. Foster Fiagg.
