CEREC doctors.com - Q4 2016 - page 42

40 | CERECDOCTORS.COM | QUARTER 4 | 2016
C A S E S T U D Y | | | B Y M I K E S K R A M S TA D , D . D . S .
in the previous issue of cerecdoctors.com magazine,
I wrote an article titled “Efficient and Accurate Proximal
Contacts.” It outlined some simple and effective tech-
niques to get great proximal contacts on your posterior restorations.
Perfecting
Anterior Midline
(Revisited)
A CEREC Software Update
Means a Change to the Technique
Previous to that, in the Quarter 3, 2015 issue, I wrote about
“Perfecting Symmetry with Central Incisors.” This article mainly
concentrated on a method to symmetrically adjust your contact
between the central incisors and maintain that symmetry while
doing so.
However, after the release of CEREC software V4.4 in late 2015,
the technique with anterior teeth discussed in that article became
outdated. Since the midline is such an integral part of ante-
rior cosmetics, I felt it necessary to revisit the topic and update
everyone on how to get a perfect midline in V4.4.3 (current soft-
ware as of writing this article).
The case I will use as an example is treating tooth #8 and #9
(Fig. 1). (Note: This case was completed in 2014 and, if you
would like to reference how I planned this case using Photoshop
Elements, please revisit Q4 2014’s “Simplified Smile Design.”)
Often, when I’m doing smaller anterior cases, I prefer to mock
the case up in composite instead of using a wax-up or Biogeneric/
Biojaw (Fig. 2). This helps not only to visualize the desired shape
and size of teeth in the mouth before you begin, but also so you do
not over-reduce the teeth with depth cuts.
After prepping and imaging the teeth, the Model Axis must be
set next. This step is imperative to proper contacts when doing
Biogeneric Copy. The proper way to set it is by concentrating on
the left two windows. The upper left has the midline perpendic-
ular to the incisal edge, and the lower left has a flat plane with the
centrals not too retroclined or proclined (Fig. 3).
When prepping and planning anterior teeth, there are many
techniques to leverage time and efficiency. However, it is always
a good idea to prep both central incisors at the same time (Fig. 4).
Fig. 1: Pre-op
Fig. 2: Intraoral mock-up
Fig. 3: Model Axis stage