Sintered dental zirconia has whiteness and translucency that very much resembles a natural tooth. Therefore, it is easy to achieve very aesthetic result in full contour zirconia restorations. Monolithic zirconia restoration is the most solid restoration possible. As there is no chemical bond between zirconia and ceramic, any porcelain on functional surface might delaminate in the course of time. This is especially true for posterior crowns and implant based restorations. Sintered zirconia is a very dense and highly acid proof material which prevents the absorption and surface accumulation of pollutants (like plaque). Monolithic zirconia restorations give a patient amazing “clean” sensation and greatly contribute to healthy tissues. The main objection to monolithic restorations comes from the perception that they are too abrasive for the opposing natural teeth. We should not confuse the strength of zirconia with abrasiveness. The surface of zirconia is very dense, smooth, stable and non-aggressive. In the studies done in recent years it was proven that monolithic zirconia is the least abrasive of all restorative materials and even less abrasive then natural teeth.
Here are some commonly asked questions and answers about dental zirconia, it’s use and reliability as a quality dental restoration materiel:
1. Do zirconia crowns require special prep?
No. Today’s process of creation of zirconia crowns allows accepting all preparation styles and guarantee exceptional fit (marginal and otherwise). With monolithic zirconia, prep can be very conservative. With as little as 1 mm clearance beautiful and very solid monolithic crown can be created.
2. Do I need to use water-spray turbine to grind zirconia?
Yes. Zirconia is a very bad heat conductor. Grinding without water-spray can create an extremely hot spot on the surface of the crown (over a 1,000ºC). In those temperatures the structure of zirconia in this spot can change, which will lead to creation of micro cracks and weakening of the restoration.
3. Do i need to use special tools to work on zirconia crown?
We recommend using fine diamonds for zirconia. Fine bur will remove/cut zirconia very well and will last longer. Medium or rough burs get clogged fast with fine zirconia dust and will not remove material, but unnecessary overheat the surface.
4. Can zirconia restorations be done on any type/brand of implants?
Yes. In our dental studio, we have no limitation in implant type or brand. In accordance with the case, direct screw retained or cemented crown on custom or prefabricated abutment can be realized on any implant system.
5. Are there any limitation to a size of span for zirconia restoration or the number of pontics in zirconia bridge?
There’s no limit to the span of a zirconia bridge or to the amount of pontics. The only condition is the right design. The larger the distance between the abutments the taller and wider the connectors should be. However, in light of the stability of this material, sound dental principles should be adhered to. In our studio we are routinely creating one piece full arch restorations and can report success since 2007. We’ve created very clear protocols for successful long span restorations and can guarantee any case that in made in our studio.
6. What type of cement should be used for zirconia restoration?
In principle, zirconia restorations can be conventionally fixed in place using any dental cement. However, it needs to be noted that zirconia does not etch, therefore for inlays and onlays, as well as for maryland bridges, additional mechanical retention should be created in preps and in the restoration.
Contact Us today to learn more about the many advantages of dental zirconia over traditional solutions such as porcelain. Our team will be pleased to provide you more details.