Fig. 1 The demo case: Porcelain veneered single crown on tooth
21 with shoulder preparation, a partially veneered bridge spanning
teeth 24 - 27 as well as a fully anatomical crown on tooth 28 –
all based on Ceramill Sintron.
Fig. 2a and b The fissures are opened slightly to larger dimensions to ensure that the designed morphology can also be repro-
duced by the cutters. This appears a little exaggerated but balances out after full sintering.
preparation. These contact parameters
can be easily and precisely defined and
set in the Ceramill Mind CAD software.
After dry milling of the Ceramill Sintron
frameworks in the Ceramill Motion or
Ceramill Motion 2, the restorations are
separated using a conventional, cylindri-
cal tungsten carbide cutter and the con-
nector areas trimmed. Rubber polishers
should not be used, as they could con-
taminate the metal that has not yet been
fully sintered.
The unfired occlusal surfaces can now be
easily and quickly customised and accen-
tuated using conventional instruments
(Fig. 3). Sculpting instruments are also
sometimes used and are excellent for re-
adjusting details. The wax-like consisten-
cy of the unfired framework greatly sim-
plifies this process andmakes the work a
pleasure (Fig. 4a and b).
Care should be taken during manual
preparation to ensure that the minimum
thickness of the framework is not detri-
mentally affected, e.g. by the fissures being
too deep or similar. The material shrinks
by 11 percent during sintering (Fig. 5).
After full sintering, the frameworks are
prepared in the conventional way for the
porcelain veneering and firing process. A
separate instrument set (tungsten carbide
cutter and/or ceramic bonded stones) is
also recommended in this case for prepar-
ing the surfaces to be veneered.
The framework is then sandblasted using
aluminium oxide grit size 110 μm and a
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