Clinical efficiency of a sodium perborate - hydrogen peroxide mixture for intracoronal non-vital teeth bleaching

Introduction/Objective The aim was to evaluate initial efficiency of sodium perborate (tetrahydrate) and 30% hydrogen peroxide mixture for intracoronal non-vital teeth bleaching ("walking bleach" technique). Methods Forty patients with discolored teeth were included in the study. Based on their history and clinical examination, causes of discoloration were classified as necrotic pulp, "endo-sealer"or unknown. The "walking bleach" technique was performed by applying sodium perborate (tetrahydrate) and 30% hydrogen peroxide mixture intracoronally to cavity dentin walls. The mixture was renewed in seven-day intervals.Tooth color was assessed visually before, during, and after the procedure using the Vita Classical shade guide (Vita Zahnfabrik, Bad Sackingen, Germany). Numerical values or shade guide units (SGU) were assigned to Vita shade tabs on a bright-dark scale. Analysis of variance, t-test, correlation and regression analysis were used to analyze the data (p < 0.05). Results On average, 26 +/- 9 days or 3-4 appointments were required for intracoronal bleaching to achieve the desired or best possible shade. Better clinical efficiency was found in the necrotic pulp group (17 +/- 6 days; 8 +/- 3 SGU) than in the "endo-sealer" group (42 +/- 13 days; 4 +/- 2 SGU) (p < 0.05). Age significantly influenced bleaching efficiency (p < 0.05).There was no significant correlation between bleaching efficiency and initial shade (p > 0.05). Conclusion Intracoronal, non-vital teeth bleaching ("walking bleach"technique) using sodium perborate (tetrahydrate) and 30% hydrogen peroxide mixture showed satisfactory clinical efficiency. Discoloration caused by pulp necrosis was treated more efficiently than that caused by endodontic sealers. Younger age had a positive effect and discoloration intensity had no effect on bleaching efficiency.