We don't use Sirona but rather Amann Girrbaach. I occasionally get a chipped margin but it is usually due to dull burs or someone touching the machine during a program. If you are using fresh burs and the machine is calibrated properly, I question the quality of the bur and the spindle.
Christopher Nelson, CDT is on LMTmag!
LMTmag.com is an online social blog and network dedicated exclusively for members of the Dental Laboratory community. Join free to connect with Christopher.