Zirconia restorations are fabricated from solid zirconia oxide
material,much like the zirconia oxide coping found in restorations such as
Lava, and Procera Zirconia. Like most metals, zirconia exhibits a strong
affinity for phosphate groups, and zirconia oxide is no different.
Unfortunately, saliva also contains phosphates in the form of phospholipids, so
when a Zirconia crown or bridge is tried in the patient’s mouth and comes in contact
with saliva, the phosphate groups in the saliva bind to the zirconia oxide and
cannot be rinsed out with water. Attempting to use phosphoric acid (which is
full of phosphate groups) to “clean” the saliva out only makes the problem
worse. The only way we have found to successfully remove these phosphate groups
from the interior of a Zirconia restoration is with the use of Ivoclean from
Ivoclar. This is a zirconia oxide solution placed inside the restoration for 20
seconds and rinsed out. Due to the large concentration of free zirconia oxide
in the Ivoclean, it acts as a sponge and binds to the phosphate groups that
were previously bound to the Zirconia restoration. Once the Ivoclean is rinsed
out, you will have a fresh bonding surface for the resin based cement to bond
to.
The protocol would be:
1. Try in zirconia-based restoration.
2. Rinse saliva out of restoration.
3. Place Ivoclean in restoration for 20 seconds and
rinse.
4. Cement restoration with resin based cement like u200 or 3M ESPE RELYX .
By Dr. Digvijay: BDS
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