Manufactured from Kuraray Noritake Dental’s proprietary zirconia powder, new KATANA™ Zirconia Block delivers aesthetic, natural-looking restorations. However, it is not only aesthetic value that this all-ceramic solution provides. Its superior mechanical properties were designed for reliable, repeatable fabrication of full-contour prostheses.

Impressive flexural strength

The multi-layered KATANA™ Zirconia Block possesses a flexural strength of 763 MPa, which is far higher than that of lithium silicate (LS) glass-based ceramics. This means that restorations made with the KATANA™ Zirconia Block can be designed to have thinner walls than those made with LS glass. This has now resulted in great mechanical properties and beautiful aesthetics that are now possible for all single-unit anterior and posterior restorations.

Fast chairside processing

Thanks to its integration with Dentsply Sirona’s CEREC® CAD/CAM system and SpeedFire™ ovens, the KATANA™ Zirconia Block is perfect for chairside processing and the fabrication of prostheses. Dentists only require 15 minutes for dry milling a crown with the CEREC milling unit and an additional 18 minutes is required for the sintering of the block.

A highly precise material

Dr Hendrik Zellerhoff runs a dental practice in Laer, located in the North Rhine-Westphalia district of Germany. As a digital dentistry and CEREC specialist, he has used the KATANA™ Zirconia Block for more than 40 cases in his practice since March 2018 and praises its perfect balance of aesthetics and mechanical performance. “Its strength is a major advantage—the bend strength totals 763 MPa,” says Dr Zellerhoff. “This means that it can even be used to create extremely thin walls, which in turn means minimally-invasive work. In addition, the margins are even more slender than on glass ceramics.” 

“Due to the fact that zirconia shrinks to the final size during the sintering process, an approximately 25 per cent oversized restoration needs to be milled out,” continues Dr Zellerhoff.

“This is executed using very fine milling cutters. Therefore, a larger workpiece is processed using smaller instruments. This leads to high-precision margins and occlusal surfaces. Only after this does dense sintering take place. The exact shrinkage factor is stored in the barcode on the block. Almost no rework is required in the occlusal or approximal areas. We even do without a try-in after sintering—we glaze immediately. This fact alone is really fascinating, even for long-standing, ‘pampered’ CEREC users.”

• 11. veebr 2019

About the Author

Dr. Adham Elsayed