Rich Rosenblatt I know that we have all run into this scenario. You have a patient in and are doing a CEREC crown. You finish prepping the tooth, take the shade, your assistant goes in the back to put the block in and signals you to come out of the room. She tells you that the B1 shade that I need is not fitting in to the MCXL milling chamber. Turns out the only B1 block I have is left over from when I had my compact milling unit and I get an error when I try to use it in my MCXL. The compact block has no notch at the base of the metal carrier. The MXCL block has a notch. I only had the block in the correct shade with no notch in it. Have no fear, MacGyver is here. Take the block with no notch and get a high speed hand piece and a 557 bur. Bury the bur into the bottom of the metal carrier and try and mimic the notch on a block made for the MCXL. In the matter of 60 seconds, those blocks that you were ready to throw away now fit your MCXL. If you take a look at the 3 blocks I have taken photos of, the left block has the notch (MCXL), the middle has no notch (Compact), and the right block has my man made notch.
