Recently when presenting in Minneapolis at the Star of The North a conversation came up about managing a single dark tooth during the restorative process. If the tooth has had endodontic therapy one approach is internal bleaching to lighten the stump shade. Often though these teeth have not been treated endodontically, and there is some evidence of increased risk of internal resorption following internal or walking bleach. A friend and excellent dentist that I know joined the conversation and shared a fantastic tip. He explained that if the tooth is treatment planned for a full coverage restoration he uses the provisional as a bleaching tray. Since then I have used this technique numerous times with great success.
I have the patient in for the initial prep and provisional. Most of the time I capture a final impression at this appointment, bite records and whatever other lab records we need and make sure the lab knows we are holding the case for final shade information and photographs. The provisional is relieved internally on all surfaces other than the last millimeter at the margins. We leave the provisional uncemented and send the patient home with several tubes of tray bleach and instructions. The patient is to remove the provisional 3-4 times per day, rinse it out and put the bleach inside the crown. The patient then puts the provisional on the tooth and wipes off any excess. The bisacryl crown acts as a single tooth bleaching tray.
So you may be thinking, how does this work? An uncemented provisional? Isn’t it sensitive? I had all of these same questions and now having done it for months I have some answers. The effect of the bleaching gel is equal to what you get with any tray application. It is incremental every day, but cumulatively you can get as light as you want based on having the patience to keep up with the process. As bothersome as patients find it when a provisional comes uncemented unexpectedly, they don’t mind at all when it is done with intention, and they learn very quickly how to take it off and on. I have only done this with anterior teeth, and we coach the patient about eating and incising food during the process. As to sensitivity I have had none, not a single patient who even mentioned this as an issue. True a good portion of the teeth have had endo therapy, but the ones that haven’t are also comfortable.
My patients have been very engaged in the process of optimizing the final esthetics, and many want to continue whitening even after I think we have adequate change for color control. Ideally I aim to get within the two shade rule between the prep color and the final shade of the restoration, and the time frame is variable. The photos show a single crown prep on an upper right central incisor. The tooth had previous endo and a core. the day we did the prep, the stump shade was a dark brown, off the shade guide. The patient had a previous porcelain fused to metal crown, disliked the dark shadow at the margin and wanted a better esthetic outcome. The next photo was taken after two weeks of bleaching with Venus Max 22% (Heraeus) using the provisional twice daily. The stump shade is now an A 3.5, and the patient presented telling me ” I need to keep bleaching another few weeks.”