Page 42 - CEREC Q1 | 2014

40 | CERECDOCTORS.COM | QUARTER 1 | 2014
| | | G A R D E L L
The OptiGuide is used again for preci-
sionuncovering. Figure9shows it inplace.
The proper sized tissue punch from the
Navigator kit is used to create the access,
and the plug is removed with a curette.
The nice band of attached tissue and the
ideal placement allowed me to do a tissue
punch uncover. In cases where there’s not
enough attached gingiva, reflecting a flap
and repositioning will help maintain the
long-term stability of the soft tissue.
After the plug is removed, a perfor-
mance temporary post is placed and
the arch is imaged. This allows for the
fabrication of a provisional for the
patient to function with. As the LAVA
Ultimate block is being milled, a scan
post and grey scan cap were placed and
imaged. The tissue punch access allows
for an almost bloodless surgery (as seen
in Figure 10). The Omnicam allows for
immediate imaging since powder is not
required, and the virtual model from the
scan is seen in Figure 11.
This set of images will be used for the
construction of a custom abutment and
cement-retained crown.
The seating of the scan post is
confirmed with taking a PA of the area
(Fig. 12). If the scan post has not seated
completely, the bone profiler from the
Navigator kit can be used to remove any
interfering bone.
The after-rough mill came out of the
milling chamber, the screw access hole
was finished in the LAVA Ultimate with
a handpiece; then it was luted onto the
performance temporary postwithScotch-
bondUniversal and flowable composite.
The flowable can be contoured to
create an emergence to support the soft
tissue. In the past, where a custom abut-
ment was fabricated and a two-week
window was needed, more time was
spent with the contouring of the provi-
sional. Now, with the introduction of the
e.max mesoblock, were are able to create
this custom abutment in a much shorter
time frame. In fact, the quick delivery of
the final abutment is advantageous, so
you can use the healing abilities of the
body to create the strongest adhesions
for soft tissue on e.max.
The fabrication of the final abutment
and final cement-retained crown is easy
to accomplish with CEREC 4.2 soft-
ware. The Abutment Design mode was
selected in the Administration screen.
When this is selected, you can see that
another selection appears: Multilayer.
Selecting this will allow you create a
perfect custom abutment from your
proposal with just a click of a button.
Enabling this does not lock you into
having to split the design into custom
abutment and a cementable crown. If
you choose to mill out a screw-retained
crown, you will still be able to do this
when you select this option.
When you advance to the Acquisition
screen, a decision has
to be made whether
or not to use gingival
mask. For a case
where the implant
is positioned supra-
gingival, I don’t
recommend creating
a gingival mask. In
this case, I did create a gingival mask
folder to help me plan out the gingival
profile of the abutment.
The catalogs are populated, the model
phase activates and the case can bemoved
forward. After the software creates our
working virtual models, we need to estab-
lish the model axis of our case and buccal
bite performed. For cases done utilizing
the scan post for intraoral imaging — as
was done in Larry’s case— there are times
when the stitching of the buccal bite may
not be perfect. In these cases, the new
Buccal Bite tool can be used. This tool will
tell the software todisregard the scanpost,
tell it that the scan post is not tooth struc-
ture and not to consider it when stitching.
The virtual mode needs to be trimmed
when doing abutment cases. Failure to
trim the virtual model will automatically
give that task to the software. This is a
task that it does not do well. The prox-
imal surfaces of the adjacent teethwill be
removed, making difficult to get accurate
contacts with your proposals. The scan
post is outlined and the tool activated by
a double-click of the right mouse button.
The option to use the gingival mask
can be selected. Many times I will not
use the gingival mask; instead I will
define the base line and customize my
gingival profile with the powerful tools
in the software.
10
11
12
Fig. 9: OptiGuide in place
Fig. 10: ScanPost and scan cap
Fig. 11: Virtual model
Fig. 12: ScanPost radiograph
9