In-Vitro Efficacy of a 2% Hydrogen Peroxide Toothpaste

Objectives: This in-vitro brushing study was conducted to directly measure the change in human tooth color after 28 days of twice daily brushing for 1 minute with a 2% hydrogen peroxide (HP) toothpaste, compared to a 0% HP matching placebo toothpaste.
Methods: 16 extracted, naturally stained human molars were cut in half and used in this study. One half of each tooth was brushed twice daily for 1 minute with 2% HP toothpaste and the other half brushed with 0% HP matching placebo toothpaste. At the completion of 28 days of brushing, the color of the tooth was measured using a Laboratory Digital Imaging System. Next, each tooth sample was cut open and the internal color of the tooth was measured.
Results: The 2% HP toothpaste provides statistically significantly more whitening (ΔWIO = 8.125) than a 0% HP matched placebo toothpaste (ΔWIO = 0.793) after 28 days of twice daily brushing for 1 minute. In addition, there was a statistically significant difference of 3.4 WIO for the inside of the tooth brushed with 2% HP toothpaste compared to the inside of the tooth brushed with 0% HP toothpaste.
Conclusions: The increase in whiteness for the teeth treated with 2% HP toothpaste compared to the 0% HP matched placebo toothpaste confirms that tooth whitening is a result of the HP in the formula. The difference in internal tooth color between the half of an individual tooth treated with the 2% HP and the half treated with 0% HP toothpaste, provides a direct measurement of the intrinsic bleaching ability of the 2% HP toothpaste.