Page 18 - CEREC Q3|2013

16 | cerecdoctors.com | quarter 3 | 2013
esthetic zone, I opted to make a zirco-
nium abutment and e.max crown. With
the release of the Ivoclar abutment block,
this step could be done in the office for
either an abutment or screw-retained,
full-contour e.max crown.
With the design of the crown
complete, the file is split (Fig. 25)
to propose an abutment reduced
under the designed crown. The
initial proposal of the abutment
will be determined by your param-
eters for the substructure that can
be set in the global parameters under
configuration or locally at the time of
splitting. The abutment was then altered
with the scale occlusal tool to place the
margin on the facial below the gingival
crest utilizing the scale tool (Fig. 26).
The scale occlusal tool with the scale
whole box checked is used to bring the
top of the abutment down if needed for
more clearance. The contours of the
abutment from the TiBase to the margin
can also be refined at this time with the
shape and form tools if needed. In this
case, it was not needed due to designing
the contours in the initial design before
the split.
The finalized abutment can then either
bemilled and sintered in the office (if you
scan body tells the software the angle
and depth of the implant.
After the scanbody is set, the soft tissue
model or gingival maskwill be displayed.
The margin of where we want our abut-
ment is drawn on the gingival mask
(Fig. 22). In this case, the tissue has
been contoured by my screw-retained
temporary, allowing a very precise
design of the contours of our final abut-
ment. This is one of the many benefits of
immediate temporization of the implant.
The restoration axis is set to align the
abutmentwith theTiBase if at all possible
(Fig. 23). This can be done in this case
since the implant was planned along the
long axis of the restoration to allow for
proper axial loading. If the implant were
angled, then the restoration axis would
be set based on the best occlusal scheme
for the restoration. This would allow the
fabrication of an off-angle abutment of
up to 20°.
The restoration was then proposed by
the software as a full-contour crown to
start. Design of the crown is done just
the same as with a regular restoration,
with the exception of below the gingiva.
Below the gingival margin, the restora-
tion must be designed to flow from the
TiBase and create a good emergence
profile of the restoration. After the
design was finalized, the gingival mask
model is placed to verify the emergence
profile (Fig. 24).
At this stage, if we wanted to do a
screw-retained crown, it can be sent to
the lab to be fabricated out of zirconium.
Zirconium is not going to be as esthetic
as e.max; and with the implant in the
Fig. 24: Emergence profile verified
Fig. 25: Crown design
Fig. 26: File split
Fig. 27: Final abutment design
Fig. 28: Final crown design
Fig. 29: TiBase prepared
Fig. 30: Materials applied to abutment
Fig. 31: Materials applied to TiBase
Fig. 32: Abutment luted to TiBase
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