Margot, the studies are absolutely right full count our Zr is lees wears natural enamel lees than Zr, but don't forget if your Dr. Makes any occulsal adjustments; which is always the case, unless you make it out of occulusion but then there goes ur cusp to fossau or marginal ridge and teeth are mobile unless they are in contact... Which will cause long term damage or discomfort to the Patient if it is out of occ. remember Zr is much more time consuming to adjust and polish down smoothly so that is why I fear full contour Zr. Is not suitable unless it's in perfect occ/contacts.
I still would like to know why a Dr would prescribe full contour Zr.?