Q: Is this a good time to invest in a digital scanner?
A: In short, we still do not recommend ANY of the chairside scanning systems. The reasons are still the same. The model printing technology is nowhere close to being accurate. Additional considerations include the cost of the scanners; some can cost as much as $40,000. These are closed systems that will be replaced with open platforms that will cost less than $5,000. We went through the same things with lab scanners. Ten years ago, they were $350,000 for a lab scanner and milling system. Now, labs can get even better equipment and technology for about $35,000. About one tenth the cost in less than ten years. Also, watch out for the data transfer fees, model fee, die fee, and margin marking fee, all of which can really add up; some systems at over $50/unit. Remakes with digital scanners seem to be higher, again because of the printed model technology. And there are many applications that cannot even be utilized with chairside digital impression systems.
The scanning technology generally works great in a laboratory setting. Although we are using a slightly different scanning technology, the biggest difference is we are scanning an already accurate stone cast. When using a chairside scan, the lab has only two choices, work completely without a model to check contacts, occlusion, margins, or contours; or rely on a very inaccurate printed model. We recently spoke directly with the technical experts on the inside at one of the large model printing centers (not a sales rep, the technical people that have to answer the complaints every day), and asked two simple questions, “How accurate are the models?” The reply, “80 – 100 microns”. A second question, “What can we use them for?” The reply, “as long as you don’t use them for margins, contacts, or occlusion, the models work fine”. So there you go, your chairside digital scanner works fine except for contacts, margins or occlusion.
If you want to test a system, have them demo scan for you and make the model on a three or four unit case, not a single. Send it to us with an impression of the same case and let us make two sets of crowns, you can see and experience the difference just like we have for many cases.
We would love to see the digital technology loop closed up as well, but not at the expense of the quality of work. When the first generations of milled zirconia started it was terrible. Not even within 100 microns in accuracy. It took more than a decade of research and pressure on manufacturers for things to evolve to where we are today. The same will happen with model printing technology, it’s only been a few years and they are not even close to the 25 – 50 micron threshold we need for accuracy.
For now, just save you money and keep using impression material for consistent, accurate results.