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A non-vital root-filled tooth can be whitened by placing dental bleach into the access cavity/pulp chamber, where it bleaches from the inside out.
The indications for intra-coronal bleaching should be fairly obvious. Simplistically, if the stain is on the outside, you don't bleach it on the inside!
This case involves periodontal therapy, enamel-plasty, internal bleaching, and cervical restoration. It demonstrates that poor shape and colour can be easily corrected in root-filled teeth without reaching for the post-crown drills.
A number of bleaching products are commercially available for internal bleaching, based on either Carbamide Peroxide, or Sodium Perborate. Sodium Perborate was used in this case, but its use has since been made illegal in the UK and Europe.
Slide show: Internal Bleaching
In this case, why was a GP point inserted into the periodontal pocket of UL1? (Slide 3)
In this case, when the UL1 was first levelled with UR1, it was left slightly long. Why?
Why is the Gutta Percha sealed off with RMGI ?
UL1 has has a yellow-brown discolouration. What is the usual cause of this?
What is the usual cause of grey/black discolouration of a single tooth?
What other common causes are there of discolouration to a single tooth?
What are the indications for internal bleaching?
What are the contra-indications to internal bleaching?
What strength bleach?
Dental bleach is available as Hydrogen Peroxide solution, or Carbamide Peroxide solution. The solutions are often presented as gels, to allow easy placement.
Generally speaking, Carbamide Peroxide has one third the equivalent strength of Hydrogen Peroxide, so 18% CbO2 is equivalent to 6% H2O2.
The higher the strength, the more likely there are to be complications, such as sensitivity (external bleaching - vital teeth) and root resorption (internal bleaching - non-vital teeth).
Home bleaching kits (external, vital) generally have 6% - 9.5% H2O2, or 10% - 38% CbO2.
In-office bleaching gels are available at up to 38% H2O2.
From November 2012, Registered Dentists are permitted to use up to 6% H2O2 (18% CbO2). Using higher strengths is illegal.
Sodium Perborate was banned in the UK and Europe after this case had been undertaken.
• Greenwall L. Bleaching techniques in restorative dentistry. First edition. UK. Martin Dunitz Ltd. 2001.
• Summitt JB, Robbins JW, Schwartz RS. Fundamentals of operative dentistry a contemporary approach. Second edition. USA. Quintessence Publishing Co. Ltd. 2001
• Tredwin CJ, Naik S, Lewis NJ, Scully C. Hydrogen peroxide tooth-whitening (bleaching) products: Review of adverse effects and safety issues. BDJ 2006; 200 (7): 371-376
• Freccia WF, Peters DD, Lorton L, Bernier WE. An in vitro comparison of nonvital bleaching techniques in discolored teeth. JOE 1982; 8(2): 70-77.
• Plotino G et al. Nonvital tooth bleaching: A review of the literature and clinical procedures. JOE 2008; 34(4): 394-407.