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QUARTER 4 | 2014 | CERECDOCTORS.COM | 19
THERE ARE NUMEROUSMATERIALS AVAILABLE FOR
CLINICIANS TOMILL CHAIRSIDEWITH A CAD/CAM
SYSTEM. DO YOU FEEL THE IDEALMATERIAL EXISTS
TODAY?WHAT DO YOU FEEL ARE THE CHARACTERISTICS
OF THE IDEALMILLED RESTORATION?
Well, let me tell you that the ideal material is the
natural tooth: enamel and dentin. This brings me to
something very new that we did and something that
may be a game changer in the CAD/CAM world.
In a recently published work1, we have been able
and used to produce 100 percent biomimetic resto-
rations. An irony ... What if God gave us thirdmolars
as a “spare wheel?” Do not throw them out please.
INWHAT SITUATIONS DO YOU FEEL THAT PORCELAIN
IS THE INDICATEDMATERIAL OF CHOICE? INWHAT
SITUATIONSWOULD YOUNEVER USE ALL CERAMIC?
WHAT ARE THE ADVANTAGES OF RESIN OVER
PORCELAIN, IF ANY?WHERE DO YOU FEEL THAT
A RESIN RESTORATION IS CONTRAINDICATED?
I believe that the decision to use
ceramics or composite resins should
not only be based on the properties and
performances of those materials, but also
their location in the arch and the antag-
onistic teeth. For poster­ior teeth, our
research (in-vitro fatigue resistance) is
clearly pointing at high-performance
polymers (HPP) and lithium disilicate
materialsas thewinners. Iamparticularly
impressedwithblocksmadeof composite
resin that I like to call HPP because,
unlike hand-made restorations that
are full of interlayer gaps and porosi-
ties, the block can be manufactured
under much better conditions using,
for instance, heat and pressure. The
mechanical properties are potentially
improved, which gives them a stunning
combination of flexibility (main property
of dentin) and friendly wear-resistance
(property of enamel).
Polymers also have many practical
advant­ages compared to ceramics like speed of mill
(no post-mill firing), millability in thin layers, much
reduced wear of milling burs and less risk of fracture
during pre-cementation functional occlusal tapping.2
Finally, resins have this chameleon effect (they blend
very naturally over dental tissues).
The price we “pay” for all of this is the progres-
sive loss of shape and surface texture, which
does not happen when using ceramics, of course.
Ceramics also have this wonderful surface finish (if
handled appropriately) that facilitates hygiene and
maintenance.
to produce a “natural” restoration from a wisdom
tooth extracted from a donor (Fig. 2). The trick was
to position the natural crown ideally to avoid any
occlusal adjustments of the natural occlusal surface
while having a perfect fit with the preparation. This
could be achieved only with a CAD/CAM system.
This breakthrough opens the door for other full
biomimetic solutions, including implants, etc. Ironi-
cally, while millions of dollars are spent on research
on stem cells to produce a “biomimetic tooth in a
Petri dish,” countless wisdom teeth are extracted
and removed each day. Teeth that could be recycled