PDF Version - Glidewell Dental Labs

Figure 16: The next step of the Reverse Preparation Technique is
to prepare the gingival margin. Unlike in dental school where I was
taught to prep the margin as the last step of the preparation, I now
do it as the second step. In my experience, doing it at the end feels
10 times harder than doing it at this point. In fact, most dentists
who try this never go back to placing the margin at the end of
the procedure.
Figure 17: The 801-021 bur (Axis Dental) is a round diamond, and
when used parallel to the tooth, it cuts a half-circle into the gingival
third. This ensures we have enough reduction in the gingival third
for an esthetic restoration that won’t have an over-contoured
emergence profile. An ugly gingival third is almost always the cause
of ugly anterior crowns.
Figure 18: With the gingival margin prepped on all teeth, we are
now going to place incisal edge depth cuts. The three rings that
are visible on the shank indicate that this is a 1.5 mm depth cutter,
which will provide an adequate amount of reduction for the dental
technician to build the desired incisal edge. This is especially true
when working with IPS e.max ® crowns (Ivoclar Vivadent; Amherst,
N.Y.), because they can be cut-back and layered for the best
esthetic result.
Figure 19: The benefit of using a self-limiting depth cutter is not
having to guess like you do when using a #330 bur as a depth cutter.
The shank is much wider than the cutting surface of the bur,
making it impossible to go too deep. Once the shoulder of this bur
is on the incisal edge, I can move the bur to the lingual to complete
the depth cut.
28 www.chairsidemagazine.com