Creation porcelain is the finest dental ceramic
available. Its unique qualities set it apart from other products on
the market. In order to achieve optimal results with Creation, it
is necessary to follow some rules of thumb that will ensure a trouble-free
and satisfying build-up process.
1. Wetting the porcelain:
Keep the build-up moist, but be careful not to over-wet the porcelain
when initially mixing it with Modeling Liquid. Creation Modeling Liquid
has tremendous body and will allow the porcelain to "stack"
very well even if it is over-wet. This can result in excessive shrinkage
and tearing of the porcelain when fired. New users may want to dilute
the liquid with distilled water.
2. Dry time: Dry the build-up
under the heat of the muffle, not at room temperature on the bench.
A programmed cycle of 6-8 minutes at a temperature of 500°C works
for most furnaces. When the build-up is complete, tap the model gently
just to bring the moisture to the surface (you're not trying to "condense"
here) and place the moist build-up right on the platform.
3. Creapast application: When
using Creapast, the goal is to obtain 50 to 70 percent coverage on
the first bake. Do not do a "slurry" bake; just apply a
healthy layer to the oxidized frame and fire.
4. Proper firing: This is
the single most important tip for achieving the proper mechanical
and optical properties of Creation -- learn to recognize the visual
indications of properly fired porcelain. Use the photos in the Creation
workbook as your guide along with Jensen's Firing Chart Supplement.
Porcelain that's not fired properly is indicated by lack of vitality,
lack of translucency, brittleness or chipping when grinding, poor
shade matching, poor bonding, and instability of porcelain shoulders.
It is much more common to under-fire Creation than it is to over-fire
it.
5. Dentins: Realize that
Creation Dentins and Opacious Dentins may have a higher chroma than
the product that you were using. They are also less translucent than
other systems in order to maintain the value. This gives you freedom
to use more translucent materials over the body, which provides vitality
and depth. Also, because of the higher chroma and greater opacity
in the dentin, you are able to work with a thinner layer of Dentin.
Cut back the Dentin more with Creation than with your old porcelain.
6. Shrinkage: Control the
shrinkage…don't let it control you. Cut the interproximals of
bridges and pierce the fossa of your posterior anatomy to prevent
tearing. If the porcelain tears next to your incision, you have not
controlled the shrinkage. Make your cuts before the porcelain is dry.
Moisten if necessary prior to cutting.
7. Re-wetting: It is highly
recommended that you do not re-wet dried porcelain with Modeling Liquid.
Instead, use distilled water.
8. Add-ons: If you have trouble
adding on to a fired build-up, make sure the first bake is properly
fired and that the second bake cycle is 10°C lower than the first.
Do not rush the dry time on second bakes. Break the glaze on the surface
to receive the add-on and wet that surface with Universal Liquid -
then place the add-on material. Do not over wet the add-on material.
In fact, mix it up slightly drier than usual, or take fresh powder
and mix it with distilled water. Do not vibrate the add-on. If necessary,
cut the add-on with Glaze Powder.
9. HTs and TIs: Familiarize
yourself with the HT and TI powders. These are colors with tremendous
versatility and they can add a great deal to even the simplest build-ups.
Two past issues of Jensen's porcelain newsletter, The Palette, were
dedicated to HTs and TIs. Ask your Account Manager for details.
10. Glazing: If the opaque
and first bake appear to be fired properly, but the glaze is unsatisfactory,
simply extend the hold time on the glaze cycle. Start with 30 seconds,
and extend or shorten until the desired degree of glaze is attained.
If you need a longer hold than 60 seconds, it's a good bet that your
porcelain is underfired on the first bake.
For more information, please call Jensen's Technical Department at
800-243-2000.
Rev. 0, 1779