The aim of this study is to measure color changes caused by two regenerative protocols over 3 months, and the effectiveness of internal bleaching. Twenty extracted human maxillary anterior teeth were used. The apex and canal were prepared to reproduce immature teeth. Teeth were divided: group 1: Triple-antibiotic-paste was applied for 3 weeks and then changed for blood until 3 months. Group 2: Blood was inoculated and sealed at cemento-enamel junction level with Biodentine for 3 months. Both groups were subjected to three sessions of internal bleaching. Color assessments were taken at baseline and at 2 and 3 weeks, 2 and 3 months, and 1, 2, and 3 weeks from the beginning the bleaching phase. Statistical significance was considered at P = .05. Both techniques produce color changes above the acceptability limit at 2 weeks. Chromatic variation caused by Triple-antibiotic-paste was intense and progressive over time. Replacement of the Triple-antibiotic-paste with blood made the color change more intense and progressive, with significant statistical differences at 2 and 3 months (T4 > T3; P = .028). The internal bleaching technique was statistically more effective in the Triple-antibiotic-paste group at 1 week (P = .002). Both techniques cause unacceptable color changes, causing Triple-antibiotic-paste more staining than Biodentine. Two sessions of internal bleaching recovered clinically perceptible color in both regenerative endodontic procedures without returning the original color.

中文翻译：

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内部漂白对三联抗生素糊剂或 Biodentine 在再生牙髓手术中使用引起的冠状变色逆转的影响

本研究的目的是测量 3 个月内由两种再生方案引起的颜色变化，以及内部漂白的有效性。使用了二十颗拔除的人类上颌前牙。根尖和根管准备再生未成熟的牙齿。牙齿分为： 第1组：应用三联抗生素膏3周，然后换血直到3个月。第 2 组：用 Biodentine 在牙骨质-牙釉质交界处接种和密封血液 3 个月。两组都进行了三次内部漂白。在基线和漂白阶段开始后的第 2 周和第 3 周、第 2 和第 3 个月以及第 1、2 和 3 周进行颜色评估。在P时考虑了统计显着性 = .05。两种技术都会在 2 周时产生超出可接受限度的颜色变化。由三联抗生素糊剂引起的色差随着时间的推移是强烈的和渐进的。用血液替代三联抗生素膏使颜色变化更加强烈和渐进，在 2 个月和 3 个月时有显着的统计学差异（T4 > T3；P  = .028）。在 1 周时，内部漂白技术在三重抗生素糊剂组中更有效（P  = .002）。这两种技术都会导致不可接受的颜色变化，导致三重抗生素糊剂比 Biodentine 染色更多。两次内部漂白在两种再生牙髓手术中恢复了临床上可察觉的颜色，而没有恢复原来的颜色。