I know many of you have been interested in the concept of fast-sintering zirconia (especially those who are chairside manufacturing).

It's an interesting topic (both on the lab side and chairside) because it obviously increases efficiency. However, traditionally it has been accepted that long-sintering zirconia will result in better esthetics and overall properties.

Over the last year or so, many companies are investing in R&D to actually change their zirconia properties to facilitate great esthetics and strength while also dramatically reducing sintering time. The first that has been successful is Kuraray Noritake and their flagship Katana product.

Starting in September, they will release a chairside product called Katana Speed. I have been testing this product and it has been fantastic. They have figured out their powders to increase strength and translucency and reduce sintering time to 9 minutes… you read that right… 9 MINUTES.

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So, how did they do this?

By changing the formulation of their zirconia powder

*Large crystals are disadvantageous to strength… So if you make the crystals more uniform, then you can decrease the size of the larger crystals and achieve higher strength.

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*In general, reducing the sintering time is disadvantageous for translucency. However, more uniform crystals will decrease the amount of small crystals and increase translucency

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Using the SpeedFire from Dentsply Sirona, you can get the product down to 9 minutes and change:

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Here is some literature on speed sintering that is starting to show, that you can do this and maintain material properties:

Here is a case that I did (admittedly not a work of art)…. and just polished ONLY, but it's a promising result. I am starting to do some more with MIYO for better esthetics… However, this crown took about 45 min total, which is an impressive improvement

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What do you all think?