its simple; we use a similar technique to what i am about to describe, in the design of orthotics and implant stents (with no drilled holes, which more or less twists the doctor's arm to get CT scans and do it the right way)
this is a simple process. for waxing a case like a full arch it gets a bit more complicated, but the process remains the same.
1. prep the case. you need one solid model with rough preps, and a set of singles with similar preps (given this is a case to show off your waxup skills, and not have temps milled, you can be lazy, just DONT touch the margins with a die ditch, and leave ALLL the tissue you can. model just looks better, and you get better ideas for natural eruption data).
2. scan an opposing or bite
3. each tooth do BOTH a coping AND a full contour. depending your preset anatomy library (you'll be looking to use your own if you have your own) you can also do Veneers instead of FC. Veneers is more forgiving on your preps too. the reason for this (even if you use Veneers) is the Coping output data can be used to print/mill PMMA, and have the reduction coping ready for the doctor when it comes time to prep. this makes the final product go faster as (in the case where no changes are to be made) you can print/mill everything all at once (even before the patient is prepped). wax/zirconia/pmmatemps, anything you want.
there is a slight drawback to this process though; some dentists can't prep or follow reduction guides. this makes it harder to go from start to finish on a case. sometimes doctors go very far submarginal. implants in the place of bridges is trickier to do.
for the most part though, this works. especially well with no-prep veneers. by far and away the better method (if youre good with the cad tools). but the most useful of all this is for manufacturing premade bondable PMMA orthotics, or non drilled implant surgical stents. doing waxups is fine, but proceeding from the waxup through the final stage isnt quite what ends up the final working case.
