Effect of internal bleaching on the reversal of coronal discoloration induced by triple‐antibiotic‐paste or Biodentine use in regenerative endodontic procedures

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.