Michael Miller, DDS
On two different patients - one with a "shrunk to fit" provisional and one with Improv-cemented, long-term provisionals (26 units) - a black film that looks like mildew has formed on the preparations. What is it? Is it coagulated blood? The longer it is present, the more difficult it is to remove. What do you think?
The "black stuff" is probably due to leakage, which is fairly common with "shrink-to-fit" provisionals and those cemented with provisional resin cement. It is probably not coagulated blood, but is more likely some type of precipitate.
To prevent this "black stuff" from forming, rinse the prep well, dry, and then apply Consepsis. Suction the excess and air dry it on the prep. In other words, do not rinse it off.
In addition, when cementing with provisional resin cement, be sure the cement is cured before trying to remove the excess. If you try to remove the excess before the cement has been cured, the gasket-like seal that forms between these types of cements and the tooth will most likely be disturbed, leading to the type of leakage you are experiencing. However, if you still get the black stain, REALITY editorial team member Dr. Marvin Fier suggests you try gently wiping the spot with Superoxol, using a small head applicator tip.
After treating one patient with three restorations - requiring approximately 20 curing cycles - I ordered a plasma arc light, but I`m concerned about the short heavy cord and small tip. My Optilux 401 has been easy to use. I`d like to compare the Virtuoso and the PowerPak to the Optilux 501. Is it easy to adjust to the plasma arc lights to get the extra speed and still have ease of use, or is it better to stay with the Optilux 501?
As we reported in the 2000 edition of REALITY, our bond strength and microleakage tests have supported the use of high-speed curing of 10 seconds instead of 40 seconds for a conventional light. We are currently repeating some of those tests just to be sure, as well as expanding our investigation to include depth of cure and hardness.
The small tips and the stiff cords are definitely a concern. These lights are not as user-friendly as a conventional halogen light.
Do you routinely recommend removing all old composites and designing the laminate to replace the entire old filling, or refilling it at the time of preparation? What would you recommend for a patient who desires a laminate or porcelain crown, but has a thin tooth and an extremely large filling? Preparing it for a crown would leave almost nothing, unless I did a deliberate endo and a post and core. I am also concerned with the bond strength - or lack of - to composites placed prior to bonding the laminate or crown.
Our current feeling is to have all existing restorations totally encased by the new restoration. This means that teeth with mesial and distal through-and-through restorations are usually best treated with crowns, not veneers. However, the crowns can have minimum reduction with the lingual margins supragingivally. If you have a thin tooth faciolingually, reducing it for a crown can be scary. Therefore, you may choose to only veneer these types of teeth, unless you perform pre-orthodontic space recapture. Many thin teeth seem to be found in patients with deep overbites. Once the overbite is corrected orthodontically, you can still do a crown, but tooth reduction can again be minimized to preserve the integrity of the tooth.
Dr. Miller is the publisher of REALITY and REALITY Now, the information source for esthetic dentistry. He is an international lecturer and a fellow of the American Academy of Cosmetic Dentistry, as well as a founding member. He maintains a private practice in Houston, Texas. For more information on REALITY and to receive a complimentary issue of his monthly update, REALITY Now, call (800) 544-4999 or visit www.realityesthetics.com.