GC EUROPE FujiCEM (Automix) - Manual (Page 4)

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What is today’s first choice?
Zinc Phosphate
Zinc Phosphate has
been used for over a
century for luting
restorations involving
metal and so it was the
natural first choice against
which the newer cements
were measured. Even
today, being familiar,
cheap and relatively easy
to use, it has remained
some dentist’s
first choice.
However, Zinc
Phosphate cement does
have certain weaknesses
and inherent problems.
Post-op sensitivity is
possible as it can irritate
pulp. It has no sealing
properties, no therapeutic
activity, high solubility in
oral fluids and no
translucency.
It is also not suitable for
luting modern ceramic
and composite materials.
Last but not least, it has
no intrinsic adhesion,
relying solely on low to
moderate mechanical
retention. In this adhesive
era, bonding strength is
very important as it can
help save tissue and
enable luting even in
cases where only minimal
retention is available.
Quite simply, in many
areas, Zinc Phosphate has
been superseded in
performance by all the
new luting cements. Even
for the most basic of
procedures, the role of
Zinc Phosphate as a first
choice cement should be
reconsidered.
Superseded as first choice for routine luting?
POTENTIAL SENSITIVITY
NO SEALING ABILITY
NO FLUORIDE RELEASE
HIGH ORAL SOLUBILITY
ONLY MECHANICAL
RETENTION
MOISTURE CONTROL NEEDED
POOR SEALING ABILITY
DIFFICULT TO USE
COSTLY IN TIME AND
MATERIALS
NO FLUORIDE RELEASE
LOW COMPRESSIVE
STRENGTH
PLASTIC DEFORMATION
The role of
Polycarboxylate?
Mention should also be
made of another type of
zinc oxide-based cement
called Polycarboxylate.
This cement chemically
adheres to tooth structure
and metals, and has a
higher tensile strength
than Zinc Phosphate with
no post-op sensitivity.
However, it is not as
popular mainly because of
its lower compressive
strength and greater
plastic deformation.
If used, Polycarboxylate is
best suited for luting
single metal restorations
in low stress areas and not
long span prostheses.
Composite Resin Cement
Excessive as first choice for routine luting?
Composite Resin is the
most used luting cement
for aesthetic restoration
with ceramics and
composites. This is
because if used correctly,
they have the highest
strength and bonding
capability. They are also
virtually insoluble in the
mouth and are available in
a wide range of shades
and opacities.
But for routine luting
these cements can give
certain problems. Their
correct use requires many
technique sensitive steps
and use of a multi-step
bonding agent makes
them very expensive.
Viscosity or film thickness
can be too large,
increasing the risk of
incomplete seating of the
restoration. There is no
relevant fluoride release
and since moisture
control is needed the risk
of microleakage exists,
possibly resulting in
secondary caries.
Using Composite Resin
other than as a possible
first choice for aesthetic
restorations could be
considered excessive,
even wasteful, particularly
if non-aesthetic
restorations are your
norm.
Indicated for Aesthetic
Restorations only. Indicated for Metal
Restorations only.