Clinical Tips for Polishing Ceramics: e.max and Zirconia
Adjusting occlusal contacts is frequently required at the time of try-in and/or post-insertion. If there is a minor occlusal adjustment needed, my suggestion is to use only a rubber abrasive polishing wheel and not a diamond. A diamond is needed only if there is a significant adjustment to be made.
If a diamond is used in this process, proper polishing of the surface is necessary to achieve a smooth surface. A polished ceramic surface is less abrasive than one that is glazed, so there should be no need for re-glazing of the restoration. The larger the diameter of the polishing wheel used, the more efficient and effective the process. A point may be necessary to get into the depth of the anatomy, however it is the least effective because of its size.
The three key points for this procedure are:
1. Diamond: Use a fine grit diamond in a friction grip slow speed handpiece. An electric handpiece is more effective than one that is air driven. Run the handpiece at 20,000 RPM with water spray. Avoid a high-speed handpiece because it will create excessive heat and trauma in the ceramic. A light touch is required to avoid excessive heat and vibration. You will then need to use a rubber Polishing Wheel. (Left: Fine Diamond.)
2. Rubber Polishers: I use Brasseler’s Dialite LD (lithium disilicate) and ZR (zirconia) series. Each have a medium and a high shine wheel. An electric handpiece should run at 10,000 RPM to a maximum of 15,000 RPM, with only light pressure used. Electric handpieces have constant torque even at a slow speed, so they are more effective than air driven handpieces. Begin the process with the medium shine wheel. This step should take approximately 30 seconds. Next use the high luster rubber wheel with the same technique as described above. (Right: Medium Dialite LD.)
3. If you use Polishing Paste: Polishing paste should be used with a bristle brush wheel in a slow speed latch handpiece. The product I use is the Dental Ventures of America Zircon-Brite ‘G.’ This is very effective for polishing the grooves in the posterior anatomy. (Left: High Shine Dialite LD.)