Darin O'Bryan, D.D.S. There are times when you are going to have an abutment that sticks out of the top of the tibase. This can happen when the patient has small teeth and to place the implant any deeper is not feasible. You will end up with a design that looks like this:
Lucky for us the software does not take into account the metal of the tibase when milling the crown. This means we are not going to have minimal thickness issues with our crown. And the milled crown will seat just fine on the abutment.
But not with the tibase supporting the abutment:
This is easily corrected by using the abutment as a reduction coping once it is put on the tibase. I use a carbide finishing bur and copious irrigation to reduce the heat generation into the zirconium abutment and the tibase.
Once this is accomplished the abutment, tibase and crown all fit together without a problem.
