Internal Bleaching Re-Examined
Internal bleaching has a complicated history that many people, including dental professionals, don’t understand fully. In a recent Q & A, whitening science expert Dr. Rod Kurthy provided a succinct explanation about how internal bleaching works, why it produced some unfortunate outcomes in the past, and how you can safely perform the procedure in your practice today. Below is a quick summary, but you can read Dr. Kurthy’s full answer here.
When peroxides break down, they give off a variety of aggressive radicals (hydroxyl radicals, perhydroxyl radicals, superoxide radicals, oxygen ions, and hydrogen ions). In the past, when peroxide was placed inside the root canal chambers of endodontically treated teeth (internal bleaching), those radicals traveled down the dentinal tubules and into the periodontal ligament (PDL) space. There, they caused chemical burns, which stimulated stem cells to turn into cementoblasts that reproduce and resorb the root structure (external root resorption). In some cases that led to tooth loss.
Times have changed and researchers discovered that placing a restorative plug at the bottom of the root canal chamber and into the root canal orifices can prevent peroxide radicals from percolating down into the PDL space. Initially, many materials were tried, including amalgam, intermediate restorative material, cements, glass ionomer, resin monomer/compomer, and composite. In the end, the results showed that ionomers provide the best result because they’re self-adhesive and expand rather than shrink during polymerization. No bonding is necessary and they routinely create a very tight seal.
When you follow proper technique, you can safely perform internal bleaching and provide patients with the outcomes they’re looking for. To access KöR Whitening’s internal bleaching instructions, visit korcommunity.com. Follow these instructions carefully to ensure the best results for your patients.