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with minimal sensitivity. This bonding agent required no etching
of the dentin, which was desirable as that is one fewer step the
clinician needs to worry about with regards to dentin sensitivity.
The key to success for this material was its proprietaryMDP adhe-
sive monomer which increased the bond strength of dental mate-
rials to hydroxyapatite.
Today, the newest generation of adhesive cements that utilizes
the same successful MDP adhesive is Panavia V5 from Kuraray
Noritake. This unique adhesive is an amine-free, dual-cure, color
stable, fluoride-releasing resin cement.
Being dual cured is a desirable property for resin cements
because it gives the operator confidence that the cement will set
properly in the absence of light — which is often the situation if
the ceramic is thick, the restoration is opaque or if the margins are
deep. The downside of dual-cured cements is that the amines that
are used in the dual-cured reaction can turn the cement darker
than what the clinician started with.
So, if a clinician cements a restoration that is shade A1 and a
cement with amines is used, the restoration, with time, would
discolor to maybe an A3 shade. This phenomenon of color shift
has limited the use of amine containing cements to non-esthetic
areas and areas where the cement does not affect the final shade —
such as a restoration with thick ceramic.
Panavia V5 is amine-free, which results in a color-stable cement.
Since the cement is color stable and is dual cured, clinicians can
be confident in using the cement in anterior esthetic areas. With
other dual-cured cements, this use would not be possible because
of the phenomenon of color shift as previously discussed.
Another desirable characteristic of a dental adhesive complex is
ease of use. The aforementioned potential sensitivity has less to do
with etching the dentin and more to do probably with improper
technique (as mentioned previously).
While there was a rush by manufacturers to avoid sensitivity
with self-etching bonding agents, there was also a rush by manu-
facturers to simplify the bonding process. Multiple steps can
contribute to the sensitivity as it makes the procedure more tech-
nique sensitive.
It can be assumed that it is easier to screw up a procedure with
six steps than one with just two. Therefore, it can also be assumed
that, by minimizing the number of steps, we could potentially be
closer to minimizing sensitivity.
Panavia V5 wins another nod of approval because this is a one-
bottle system. The clinician applies the single bonding agent to
the tooth structure for 20 seconds, and then air dries the agent.
A separate ceramic primer is applied to the restoration and dried.
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P U R I
The Panavia V5 cement is then used to cement the restoration. As
soon as the cement touches the bonding agent, the cement starts to
set up. This results in complete polymerization of the cement. The
clinician must be aware of this phenomenon as prudence must be
used in ensuring that the cement does not set up too quickly there-
fore preventing the restoration from properly seating.
CLINICAL TECHNIQUE
The process to use the Panavia V5 system is straightforward and
results in bond strengths that are considered high by industry stan-
dards. Not to mention, due to the fact there are a minimal number
of steps and no etching or rinsing of the dentin, the process is done
with minimal sensitivity to the tooth.
The first step is to prepare the surface of your restoration. If a
zirconia restoration is used, air abrasion of the internal surface of
the restoration is the recommended technique. All other ceramics
should be treated with hydrofluoric acid and rinsed. The amount
of time the restoration is exposed to the hydrofluoric acid should
be verified by the individual manufacturer.
After the surface of the restoration is treated, the tooth surface
needs to be prepared next. Panavia V5 adhesive is scrubbed onto
the tooth structure for a total of 20 seconds. The 20 seconds is
necessary to ensure thorough penetration of the smear layer that
is on the dentin as no acid etching is used. Improper scrubbing has
been shown to be another contributing reason for sensitivity.
After both surfaces are prepared, the cement is placed in the
restoration and the restoration seated. The cement is available
in multiple different shades and the appropriate shade should
be used. For esthetic areas, appropriately matched try in shades
are available that allow the clinician to verify the shade prior to
complete polymerization.
Once the restoration has been seated and excess cement is
removed, the cement is fully polymerized with a curing light.
SUMMARY
Adhesive dentistry, while it has its challenges, can provide
significant advantages to the CEREC clinician. An ideal adhesive
cement that is color stable, available in multiple shades and has a
minimal number of steps is desirable for ease of use and a reduc-
tion of complications. Panavia V5 satisfies this criteria and will
no doubt be of use to CEREC clinicians in their daily restorative
routine.
For questions and more information, Dr. Puri can be reached at
