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Updated: Aug 3, 2026
Quantification of Hypopigmentation Activity In Vitro
Published on: March 6, 2019
Clinical evaluation of bleaching agents of different concentrations
B A Matis1, H N Mousa, M A Cochran
1Department of Restorative Dentistry, Indiana University, School of Dentistry, Room S-412, 1121 West Michigan Street, Indianapolis, Indiana 46202, USA. Bmatis@iusd.iupui.edu
Objective:
The purpose of this study was to evaluate the degree of color change, any rebound effect, and sensitivities associated with using 2 different concentrations of carbamide peroxide in vivo.
Method And Materials:
Twenty-five subjects used 10% and 15% agents in trays for 14 days on different sides of their maxillary arches. Subjects returned in 3 days and at 1, 2, 3, and 6 weeks for evaluation of color change and rebound effect. Shade matching, photographic means, and a colorimeter were used for evaluation. Subjects self-reported gingival and tooth sensitivity on a scale of 1 (no sensitivity) to 5 (severe sensitivity).
Results:
After 2 weeks, delta L*, delta a*, delta b*, delta E* and delta shade guide rank means for the 10% whitening agent were 6.50, -1.37, -4.63, 8.79, and -15.40, respectively; for the 15% agent, they were 8.72, -1.63, -5.90, 11.03, and -16.59, respectively. After 6 weeks, delta L*, delta a*, delta b*, delta E*, and delta shade guide rank means for the 10% whitening agent were 3.04, -0.99, -3.19, 5.13, and -13.13, respectively; for the 15% agent, they were 3.48, -1.01, -3.60, 5.58, and -13.65, respectively. Means for gingival sensitivity were 1.18 and 1.21 for the 10% and 15% agents, respectively; means for tooth sensitivity were 1.21 and 1.26 for the 10% and 15% agents, respectively.
Conclusion:
All 3 methods of evaluation revealed a significant difference in the tooth lightness achieved by 10% and 15% products at 2 weeks but no significant difference at 6 weeks. No statistically significant difference was found in gingival or tooth sensitivity.
