ABSTRACT
Aim To evaluate the bleaching efficacy of 16% carbamide peroxide, 30%hydrogen peroxide for intracoronal bleaching of root filled discoloured tooth. Methodology Extracted teeth were artificially stained using human blood then centrifuged under 3,200 rpm speed for 30 min thrice daily for a period of 2 days to enhance penetration of the haemolysed red blood cells into the dentinal tubules. The precipitate was removed, and the teeth were immersed in the remaining haemoglobin-rich haemolysate for further 2 days, centrifuging it thrice daily for 30 min. The resultant discoloured teeth were then washed in distilled water. Root canal treatment was performed. After obturation, a 2-mm intermediate base of Intermediate restorative material IRM was placed to 1-mm apical to the cementoenamel junction. Teeth were divided into three groups with 10 teeth per group. Intracoronal bleaching was performed using either 35% carbamide peroxide gel (group CP) in one group, 35% hydrogen peroxide gel (group HP) in another group and distilled water in the control group as the third group. The bleaching agents were replaced after 5 days. The shade of the teeth was evaluated at day 0, 5 and 10 using VITA Zahnfabrik, Bad Sa¨ckingen, Germany) shade guide. The results were analysed using Kruskal–Wallis one-way analysis of variance and Mann–Whitney U-test. Results When superoxol and control group are compared, there shows a clear difference of significance between these two materials. But when superoxol and carbamide peroxide are compared, there is no difference of significance. Both superoxol and carbamide peroxide showed same results. Both are effective bleaching agents. Conclusion In our study we noticed that 16% carbamide peroxide and 30% hydrogen peroxide are equally effective in the treatment of intracoronal bleaching which we observed in a 5,10,15 days of regular intervals.