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44 | CERECDOCTORS.COM | QUARTER 2 | 2014
| | | K A U F M A N N - J I N O I A N
PLACEMENT
The VITA ENAMIC restorations are
already virtually complete following
milling. They should not be placed again
in a furnace. Instead, only chemical
glazing or simple polishing remains to
be carried out. In this case, the restora-
tions were particularly small and deli-
cate, and so were not polished in the
laboratory. The veneers were delivered
to the practice unpolished and first veri-
fied in the patient’s mouth using try-in
pastes. In some instances, the color of
VITA ENAMIC restorations can appear
to be too bright until they come into
contact with materials such as paste.
Only at this point can the play of colors
and the “chameleon effect” of the mate-
rial be evaluated.
Placement into position was
performed using Variolink Veneers
from Ivoclar Vivadent (Schaan, Liech-
tenstein). According to the manu-
facturer, the hybrid ceramic must
be etched for 60 seconds in order to
achieve a secure bond. When placing
thin VITA ENAMIC veneers into posi-
tion, the use of dual-curing composites
should be avoided in accordance with
the working instructions, as these can
cause slight discoloration (yellowing)
once curing has completed. Purely
light-curing composites are preferable
for this reason. A microbrush that is
adhesively bonded to the veneer using
light-curing bonding or a glue stick can
be used as a holder.
Fixing the veneer with a finger allows
more uniform distribution of pressure
during adhesive placement.
HIGH-GLOSS POLISHING
Polishing instruments were developed
for reworking the hybrid ceramic that
are specifically adapted to the properties
of the material. Using these instruments
is recommended in order to achieve
superior surface finishing simply, reli-
ably and efficiently. The VITA ENAMIC
Polishing Set is available in a technical
variant for laboratory use as well as a
clinical variant for use in dental prac-
tices (Fig. 14). As mentioned previously,
only final polishing was carried out in
this case by the dental surgeon. A transi-
tion area between the restoration mate-
rial and the natural tooth substance is
not discernible (Fig. 15).
In order to obtain a natural surface
shine, two steps must be performed:
first, pre-polishing must be performed
using the pink polishing instruments
while cooling withwater (7,000 - 10,000
RPM), followed by high-gloss polishing
while cooling with water using the
diamond-coated, gray polishing instru-
ments (5,000 - 8,000 RPM). Excellent
results are achieved when the lowest
RPM rate is used to perform what
Fig. 11: Shade determination
Fig. 12: The block shade 2M2
was selected
Fig. 13: VITA ENAMIC
block with fully milled
partial veneer
Fig. 14: VITA ENAMIC
Polishing Set clinical
Fig. 15: Final result
amounts to final high-gloss polishing
without cooling with water. Generally,
reduced-contact pressure must be used.
RESULT
A before-and-after comparison (Figs.
16-17) shows the considerable impact that
was achieved using comparatively simple
methods: the former “Twilight” girl now
sports a lovely smile, her appearance that
of a completely normal teenager.
CONCLUSION
VITA ENAMIC generally allows supe-
rior restorations to be fabricated very
quickly and inexpensively. The dental
surgeon who was initially skeptical has
since become an enthusiastic fan of
the hybrid ceramic. VITA ENAMIC is
distinguished by the fact that it offers
stability and elasticity, as well as other
properties. This ensures unusually high
edge stability.With a conventional CAD/
CAMglass ceramic such as lithiumdisil-
icate ceramic, it would not be possible
to create partial, non-prep veneers in
this way. Due to their brittle character-
istics, it would have been expected that
such materials would fracture when
milling thin restoration margins of this
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14
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