Have you ever had a restoration that fit the model it was made on but not your patient's tooth? While this should be a rare occurance, this has or will happen to each of us at some point. This can be exceedingly frustrating.
As we all know there are many potential causes for ill fitting restorations. These issues can range from severe to minor; however, even the minor ones can leave us with a restoration that is not adequate. While it's best to work with your lab to correct the fit, I would like to share a simple check you can do that in some cases may save the day.
What I am referring to is checking the internal fit of your restorations for binding. I do this with a product called Occlude, which is a green or red (I prefer green) colored powder delivered using a aerosol can. It's most easily used on the inside of crowns by simply spraying a small amount inside the crown then trying the crown on the tooth. If there is binding, this spot will cause the powder to be rubbed off the crown and onto the preparation.
While a large area of binding would often indicate the need to remake the restoration, small areas can often be alleviated by minor adjustments. If you choose to attempt adjustments it is critically important to consider the material(s) the crown has been fabritacted with. Minor adjustments to restorations with a cast metal internal surface can often be done safely, but doing so on internal surfaces made of ceramics has a high risk of inducing internal fracture points and is in many cases NOT advised. In these cases your best option is to make minor adjustments to your preparation.
It's important to be clear that while this can be a useful technique, it's vitally important to understand that this is NOT something you should find yourself having to do often. It should only be used in select cases where any adjusments made are minor.
John R. Carson, DDS, PC, Spear Visiting Faculty. [ www.johnrcarsondds.com ]