CPD Dental Cam Primer

1. Dental CAM
written by Danie Alter
Subtractive Technology
April 16, 2015
The City University of New York
New York City College of Technology

2. 2
This material is based upon work supported by the National Science Foundation
under Grant Numbers 1141234.
Any opinions, findings, and conclusions or recommendations expressed in this
material are those of the author(s) and do not necessarily reflect the views of the
National Science Foundation.

3. Dental Computer Aided
Manufacturing
Subtractive Computer Aided
Manufacturing
Over the past 50 plus years, most large
manufacturing industries have used Computer
Numerically Controlled (CNC) machining process.
This is based on a process in which a power driven
tools (Mill) are to mechanically cut material with the
desired geometry while every step controlled by a
computer.
Computer Aided Manufacturing is not unique or
new to the dental discipline. In fact, CAM has been
in dentistry since the 70’s with the first operatives
to explore its applications for dentistry being Duret
and Preston2,3, followed by the innovative work of
Moermann in the 80’s; this led to the development
of the CEREC system. (Fig. 1 on page 3)
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Fig. 1 - Subtractive Computer Aided Manufacturing

4. Dental Computer Aided
Manufacturing
Digital Manufacturing Workflow
• Choosing the machining strategy.
• Depends on the type of material and degree of
complexity for the part.
• The software will virtually attempt milling as a
test. (Fig. 2 on page 4)
The benefits of Subtractive CAM
• Differently than the previously made
restorations, Computer Aided Design files
are stored for the patient and can be easily
and quickly reproduced in the event necessity
arises.
• The dental laboratory can easily achieve
sustainable consistency by utilizing CAD/CAM
and eliminating many of the unpredictable
variables. (Fig. 3 on page 4)
• The production rate are significantly increased
utilizing this technology. (Fig. 4 on page 4)
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Fig. 2 - Digital Manufacturing
Fig. 4 - Production using TechnologyFig. 3 - Eliminating Unpredictable
Variables

5. Dental Computer Aided
Manufacturing
Multiple Axes Milling
3 Axes Milling Machine
• The more simplistic of all CNC milling
apparatuses is the 3 axis milling machine,
which has the machine’s tool schematic
simultaneously control bur movement along
the X,Y, and Z planes. (Fig. 5 on page 5)
• This type of milling machine is appropriate
and applicable for most dental non-complex
restorations or applications that don’t pose an
occult surface. (Fig. 6 on page 5)
5 Axes Milling Machine
• A 5-axis milling machine is more versatile
because it controls its tool paths in five
motions continuously and simultaneously. Two
concurrent motions within the milling machine
occur; the X,Y, and Z axis movement and an
A,B axis movement in either the cutter spindle
or the block table. (Fig. 5 on page 5)
• The unique advantage to such a tool path
schematic is that continuous adjustment of
the bur’s orientation while cutting facilitates a
significantly heightened precision in the milled
product necessary for complex cases like
implants. (Fig. 7 on page 5)
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Fig. 5 - Axis/Plane Diagram
Fig. 6 - 3 Axis Milling Machine Fig. 7 - 5 Axis Milling Machine