34
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CERECDOCTORS.COM
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QUARTER 2
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2016
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A L A D A G
FINISHING
The milled restorations showed very precise margins without any
irregularities, which are often observed with more brittle ceramic
materials. This made it possible to further thin out the margins,
a process that would not have been feasible with a traditional
ceramic veneer. Figure 9 shows the veneer restorations on the
stone model prior to final contouring of the surface. Subsequently,
the veneer restorations were polished with the VITA ENAMIC
Polishing Sets technical for extraoral and clinical for intraoral
finishing. Each set contains a total of eight instruments, four of
them suited for pre-polishing and four for high-gloss polishing.
CAD/CAM PROCESSING
Once the patient was happy with the obtained appearance, the
model with thewax-upwas digitized (Fig. 4). In addition, an optical
impression of the patient’s teeth was taken using CEREC AC with
Bluecamto get a virtualmodel of the initial situation.What followed
was the computer-aided design of eight veneers with the software
CEREC SW 4.2 using the design technique “Biogeneric Copy.” The
contours of the scanned wax-up were used as a basis for the virtual
design and optimized with the “Biogeneric” technique.
Thepreparationmarginwasdefined(thiswasnecessary forcorrect
positioning of the virtual veneers, even though there was no actual
tooth preparation), the insertion axis determined and the copy line
drawn for each tooth (Figs. 5-6). The design suggestion generated by
the software required only minor manual adjustments: The margins
were thinned slightly using the “Smooth” tool (Fig. 7). Finally, the
veneers were placed in virtual blocks (it is possible to place several
veneers in one blank) (Fig. 8), and the restorations were milled with
CERECMCXLmillingmachine using VITAENAMIC blocks.
Fig. 2: Wax-up on the stone model
Fig. 3: Acrylic mock up in the patient’s mouth
Fig. 4: Scanned mock-up
Fig. 5: Definition of the insertion direction …
Fig. 6: … and drawing of the margins
