Daniel Wilson Fortunately our chairside options for bridge blocks is growing. With Ivoclar Vivadent coming out with some blocks, 3M and Katana Noritake will be releasing there STML bridge block later too. Originally I used to push the limits with IPS e.max bridges with the B32 block. I had one failure with connectors that were adequate 18mm2 but they were short. Now I tend to only do IPS e.max bridges if I am doing an anterior case or a premolar pontic.
So here is a case that I just did with CEREC Zirconia A3 in the medi S block. The challenge with CEREC Zirconia in my opinion is the opaqueness and the high value. For me, I'm always trying to tone that brightness down and give the restoration more depth of color. What has worked well for me is infiltration stains from VITA and then stain and glaze to follow. Here is a lower posterior bridge that I just delivered. After design in the software, I used my infiltration stains and then did 45 minutes drying and sintering cycle.
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I bought the Zig Detailer Brushes on Amazon for like $5/each.
After the sintering cycle, I fired the case on P4 with Empress Stain and Glaze. I used a bit of Mahogany in the grooves and for the embrasures. A little bit of A shade stain for the gingival aspect. Added very little Incisal 1 (Blue) for the translucency for the cusp tips. And then white to create accents and highlight the other colors. 
Overall this case isn't perfect, but I think it is a good option for us chairside. As an aside, I did this case in two appointments. Milled the provisional bridge with 2M2 Vita CAD Temp.
