-gutta percha, blood products, tetracycline, and necrotic pulp products can cause coronal discoloration.
-walking bleach technique can be used for whitening of discolored RCT teeth.
-typically, a paste of sodium perborate and distilled H20 is applied in pulp chamber for some time.
-heating of mixture is contraindicated as risk of external cervical resorption (by 3.9%) and radical formation is increased.
-intracoronal dressing of 30% H202 should not be used, to decrease resorption risk.
-denaturation of collagen is shown to be mechanism of bleaching agents.
-no increase in brittleness of dentin noted with sodium perborate w/ H202, but decreased tensile and shear strength.
-sealing 1-2mm below of CEJ area with composite or adhesive is advised to help prevent resorption.
-oftentimes bleach in 3-4 day cycles as needed.