Steven Schiffenhaus 
My Cerec journey began on June 5th when everything was installed at my office. Since then I have completed 23 Cerec restorations. I’ve learned a lot with each restoration. I’ve been waiting for one to be near perfect that I’m really proud of to post on here but none have met that criteria for me yet. I decided to make a collage of them all and post them together, the good, the bad the ugly. The one thing I can say about all of them is the margins were all BEAUTIFUL on the pre-op and post-op x-rays. So as much as I am down on myself for some parts of a lot of these preps in the end clinically they were all as good as or better than what I was getting from the lab as far as fit and margins.
What I learned so far:
-Early I tried to do too many things at once, 1st patient I did a DOL Onlay on #3 and #4 attempted a MODL Onlay on #4, then decided I would try my first crownlay and not do a build up and try to smooth everything and make it flow together. In the end it resulted in overmilling because without doing a build up I had “points” that could only be smoothed out by taking away what little palatal and buccal tooth structure I had left....
-In fact I tried to do the same thing on my next crown and decided I was trying to do too many new things at once while also learning my way around cerec. Decided I was going to stick to my old tool belt, build up and crowns and make them more smooth, rounded, flowing, and high & dry when possible
-I was shocked on my first few preps at the “roughness” of my margins, even before Cerec I would go over my margins with a fine diamond to smooth things out. I use Two Striper Modified Shoulder 018 coarse followed by fine. What surprised me is that I what looks smooth to my eyes looks different on the computer. Some of this is real minor roughness and some of the roughness I’m exaggerating, basically I thought what was glass smooth to my eyes was rough on the computer. All I have done to fix it is to take my fine diamond around a little slower and with a little more pressure, sort of feeling the bur level everything (when possible, patients and clinical situations aren’t always amenable to tinkering and refining, sometimes you just have to go with what you can).
-What bugs me is I still can’t see the difference in the mouth of the smoothness of my margins, I just make sure I make concerted effort to smooth them with purpose with my fine diamond, generally it works out but sometimes I’m still stumped at rough spots that show up after scanning, maybe I need to bump up from 2.5X to 3.5 or 4.5X…….
-I have always heard most dentists under-reduce. I have been using reduction burs the last year. I use a 1.5mm reduction bur through the occlusal groove and 2-3 grooves through the buccal and lingual (classic). I switched over to the meissingers two months ago. What surprised me is how often I am under-reduced even using this method. More often its on the cuspal inclines and I think I wasn’t “tilting” the reduction bur when connecting to the occlusal groove reduction. I still have this fear of pulping a tooth by reducing too much and I still don’t have the stones for the 2mm reduction bur. I have some preps that I feel like are almost 1/3rd the size of the adjacent tooth and think “no way I don’t have enough reduction” and sure enough either I barely have the 1.2mm required for e. max or I just decide I am not re-prepping and rescanning and I will just reduce the opposing. Most of the time its on molars. Which makes wonder how are people doing crownlays on molars? I think its bad luck with case selection, 2nd molars and under-erupted 1st molars, time will tell, moving forward I have been connecting the occlusal groove reduction to the buccal-lingual reductions by laying my 1.6mm diamond cylinder on its side, make sure its completely “sunk” and reducing mesial-distal
-Onalys and inlays are still tough, not as excited about them as I used to be. Feeling like if its not a very conservative onlay, I’d rather do a crown. Part of this is a have very well eductated patient baser. I got some patients jazzed about onlays because of tooth conservation and during the some of the preps wasted too much time trying to stay conservative and woul decide a little late in the prep design game to go full coverage. This would make for some long appointments. This was early on and I’ve developed a better eye for what will be good for an onlay vs a crown. Oh, and cerasmart is awesome!
All in all I did 11 e. max crowns, 3 zirconia crowns, 1 katana crown, 1 zirconia bridge (forgot to screen shot it so I put in the BW) and the rest cerasmart inlays/onlays
I can look at each of these and tell you something I seriously don’t like about each of the preps, some worse than others, either way, here they are... I am registered for level 2 beginning of August, maybe I'll see some of you there
