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QUARTER 3 | 2014 | CERECDOCTORS.COM | 37
These trends need to be carried on
through the restorations to allow them
to blend in with their surroundings. If
changes need to be made, they can be
done with fine diamond burs.
The other quality that needs to be
addressed to make a restoration blend
in is the texture. The various angles and
contours catch the light to give a certain
optical quality. The texture also makes a
big impact on how the restoration melds
with the existing dentition. If you look
at the original photo (Fig. 1), one of the
problems with the composite resin is
the texture is too smooth given what her
natural teeth look like. The texture of the
teeth will affect how the light bounces
off (Fig. 9). The smoother a tooth is, the
comes from the prominence of the line
angles in the gingival third (Fig. 7). If we
had just bulked out the gingival area to fill
the gaps between the restoration and the
gingiva, thefinal productwouldhavebeen
too square and blocky. But, by utilizing
the Gingiva Mask/Biocopy image, we
can contour the restorations to naturally
emerge from the gingiva without giving
them a bulky look.
When designing the final contours,
you want to take into account the axial
inclination, line angles and embra-
sure spaces. There is no recipe for this
when doing only one or two teeth. What
needs to be observed and mimicked are
the trends that are apparent: Does the
patient have broad, open embrasures?
5 6
8 7
SMOOTH SURFACE
REGULAR REFLECTION
ROUGH SURFACE
DIFFUSE REFLECTION
9
retraction cord is placed and the refine-
ment of the preparations is performed
with both green coarse and fine
diamonds. Now that the preparations
are complete, the preparations are then
imaged to add them to the upper arch
catalog (Fig. 3).
When the proposals are generated, the
first thing is to move them into the most
ideal position (Fig. 4). By utilizing the
Biocopy or Gingiva Mask catalog, posi-
tion the incisal edges correctly is quickly
done. The angulation of the teeth is also
changed utilizing the rotate function.
This will help align the long axis of the
restorationswith thenatural dentition. To
aid in visualizing the incisal edge position
and the angulation of the apical zenith of
the teeth, utilize the grid function (Fig. 5).
This can be toggled on and off by pressing
“Ctrl + G”.
After finalizing the contours, it appears
that the restorations are too constricted
at the gingival portion (Fig. 6). This could
cause problems with food entrapment.
This is why the Gingiva Mask/Biocopy
image was originally taken. By bringing
up the Gingiva Mask/Biocopy catalog, it
allows us to see that the constricted look
Are the line angles rounded to smooth
transitions, or are they sharp with a
definitive edge? Are the line angles of
similar contour not only with regard to
each tooth but as an overall trend?
If we look at this case, we can see that
the patient’s distal line angles are more
rounded, and the mesial tend to be a
little straighter and sharper (Fig. 8). We
also see that the embrasures are not very
broad, and the point angles are rounded.
more light gets reflected back at the eye,
causing a decrease in value. With careful
texturing and a specific polishing tech-
nique, it is possible to replicate these
natural textures.
The first step to create these textures
is to use the Incisal Variation tool.
The restorations are first linked using
the link function set to symmetrical.
Then the Incisal Variation tool is used
to create identical perikymata and