Page 24 - CEREC Q3|2013

22 | cerecdoctors.com | quarter 4 | 2013
the new cad/cam material vita
Enamic is a technological high-end
development referred to as hybriddental
ceramic. According to the manufacturer,
VITA Zahnfabrik (D-Bad Säckingen),
the dental composite exhibits a dual-
network structure which is unique in its
form and which gives it high elasticity —
compensating for the brittleness of pure
dental ceramics. From a user’s point of
view, this is beneficial in many respects.
This article offers a description of the
material concept and includes several
patient cases.
MATERIAL COMPOSITION
AND STRUCTURE
According to VITA Zahnfabrik, the aim
of the development of VITA ENAMIC
was to invent a tooth-colored CAD/
CAMmaterial with good light transmis-
sion properties that was not only suited
for chairside use, but also incorporates
the beneficial properties of available
all-ceramic and composite materials
into one product. For combination of
both materials, a porous basic body
High-tech Material for
Chairside CAD/CAM: VITA Enamic
Utilizing a Hybrid Dental Ceramic
c a s e s t u d y | | | b y D i r k O s t e r m a n n , D . M . D .
contains a dominating ceramic and a
reinforcing composite network which
are merged fully with one another,
explains VITA Zahnfabrik. Figures 1-3,
provided by the manufacturer, are used
to explain the difference.
Due to this unique dual-network
structure, VITA Enamic is referred to as
hybridmaterial or hybrid dental ceramic.
The acrylicpolymerwhichcompletely
infiltrates the ceramic network in VITA
Enamic is supposed to lead to flexibility
and elasticity of the materials. This
makes it less brittle and not as hard as
pure dental ceramic. Thus, restorations
made of VITA Enamic are highly antag-
onist friendly. Overall, the presented
material properties indicate that the
hybrid dental ceramic might be partic-
ularly well suited for patients in which
extraordinarily high shear and compres-
sive forces may occur (e.g., in patients
with parafunctions or bruxism). Up to
now, the material is only released for
patients with normofunction.
OVERVIEW OF PHYSICAL-
MECHANICAL PROPERTIES
According to the manufacturer, the flex-
ural strength of VITA Enamic is about
150 to 160 MPa and thus significantly
above the required values of ≥ 50
MPa and ≥ 100 MPa defined in the
ISO standards 10477 and 6872. At
the same time, the material’s modulus
of elasticity of 30 is similar to that of
human dentin. This is combined with
a Weibull modulus of 20 — a value that
is supposed to reflect a high material
reliability. Furthermore, the material
allegedly convinces with an extremely
made of ceramic is infiltrated with a
mixture of monomers, which is cured to
form a polymer. The mixture of mono-
mers consists of the matrix monomer
urethandimethacrylate (UDMA) —
which is of aliphatic nature — and the
co-monomer triethylenglycoldimeth-
acrylate (TEGDMA). The composi-
tion of the ceramic is identical to fine-
structure feldspar ceramics enriched
with alumina. The anorganic proportion
of ceramic particles is approximately
86 percent by weight, or 75 percent
by volume, and the amount of organic
polymer is about 14 percent by weight,
or 25 percent by volume.
Explaining the structure of the mate-
rial, the manufacturer points to the
fact that VITA ENAMIC is not a tradi-
tional composite material like Lava
Ultimate (3M ESPE, D-Seefeld). The
latter is composed of a polymer matrix
that is reinforced by ceramic fillers.
These ceramic particles, however, are
embedded into the polymermatrix sepa-
rately, and are not connected to each
other. VITA Enamic , on the other hand,
Fig. 1: Schematic representation of
the dominating ceramic network in
VITA Enamic
Fig. 2: Schematic representation of the
polymer network that infiltrates the
ceramic network
Fig. 3a: Comparative representation of the
material structures of VITA Enamic
with a fine dual-network structure …
Fig. 3b: … and a
traditional dental
composite
1 2
3a 3b