Most dentists can agree that the passion they feel for the crown they just seated is connected to the function and esthetics of the restoration. No one can discount the importance of seamless margins, excellent contacts or a crown that fits well, but what critical metric is missing here? Well, how long did it really take you to seat this crown? Did you have to grind a lot and polish the occlusion and-or spend lots of valuable time adjusting the contacts? Does your feeling about a crown change after you spend over 30 minutes grinding and adjusting? Of course it does and that is why (seat time) is the most important metric of all!
There are many reasons that crown seat times are a mammoth problem and we all know how aggressive crown adjustments will likely affect the longevity of any restoration. I have spent a dental lifetime working on and charting this seat time metric and as far as I can tell, we are the only Lab in the country that publishes their crown seat times. Through model equilibration, removing arch form distortion and more, we have bonded with our clients to keep the seat time metric low. Just remember that stone or digital models don’t have a periodontal ligament, so why wouldn’t the lab equilibrate the models until the facet’s touch? Figure (A-B) Of course we use two solid models to make our contacts and everyone should know that studies as far back as the 70’s, leave no doubt that pinned models are contrary to accurate contacts. Figure (C-D-E)
In the beginning, our feedback cards served us very well because they helped us receive steady communication and motivated us to get better. Fifteen years ago, our feedback cards became GREAT when we added those four little words, “time to seat case” and don’t forget to check one of the three faces on the feedback card. (see card below) These cards are a real driver for us, so here are the simple rules: Start the minute clock when the temps are removed and you are ready to cement. End the minute clock when the cement is cleaned up and the patient is ready to go. Please deduct time spent visiting with the patient or attending another operatory.
Take a look at the graph below to view our 2017 crown seat time. Our seat time metric is established each month by simple division. Number of total minutes divided by number of total units, equals average seat time per crown. We are proud of our seat time average and we are proud of the men and women we serve. Seat appointments should be fun!