It requires adding stains to the porcelain to match the adjacent teeth
since the restoration is milled from a solid block of glass with very
standard basic shades.
I am not conviced that this type of restoration will work for every
tooth in the mouth. For a busy practice and for patients who aren't
picky about how the restoration matches everything else or for
restorations that are in the back out of view but not too far back
where there is risk of fracture this will work.
The software and hardware keeps getting better and doctors need  to
constantly upgrade for yet another $100K. I am not sure of the cost
effectiveness because dentists that use this system forget to add the
cost of their time to work the cerec 3d. Certainly by having the doctor
own the machine he/she can by pass the lab sales tax on the cost of the
labour plus materials, in otherwords the tax would only involve the
ceramic ingot vs a dental lab where the tax involves the materials and
labour to fabricate the restoration. At least this is true in
California and I am always for no tax on dental prosthetics because
this is unethical and unfair to the general public who absorb this cost
indirectly and for that reason maybe one day I'll own such a machine.