Concentration of Hydrogen Peroxide in Various Tooth-Whitening Products

The purpose of this study was to determine the concentration of hydrogen peroxide in various professional and over-the-counter tooth-whitening products and to compare it to the manufacturer’s given concentrations. Furthermore, some manufacturers do not provide details about the concentration of hydrogen peroxide or carbamide peroxide in most over-the-counter tooth-whitening products.

Method:

The peroxide concentration of sixteen commercially available tooth-whitening products was determined by oxy-reduction titration method. The process is based on the principal that the reaction of hydrogen peroxide with excess potassium iodide in the presence of an ammonium molybdate catalyst produces triiodide ions, which are then titrated with a standard thiosulphate solution.

Result:

The hydrogen peroxide concentration in various dentist-supervised bleaching products ranged from 3.02% (Yotuel Patient)  to 37.08% (Opalescence Boost). The hydrogen peroxide concentration in over-the-counter whitening products ranged from 1.24% for White Glo to 5.57% for Speed White. Colgate Plax whitening rinse showed more than 1% hydrogen peroxide concentration while for other whitening toothpastes and oral rinses it was lower than 0.05%.

Hydrogen peroxide concentrations of professional tooth-whitening products differed from the expected concentrations of manufacturers. Yotuel Special was expected to have 35% hydrogen peroxide concentration but found to be only 27.19%. Opalescence Treswhite Supreme was expected to have a 10% hydrogen peroxide concentration but had 8.98%. Of the three 10% carbamide peroxide products Yotuel Patient showed the lowest hydrogen peroxide concentration of 3.02% and Nite White ACP showed the highest concentration of 3.75% while Opalescence PF had a concentration of 3.40%.

Conclusion: Professional (dentist-supervised) products showed peroxide concentrations that differed marginally from the expected values. The concentration of hydrogen peroxide in over-the-counter tooth-whitening products ranged from 1.24% to 5.57%. Peroxide concentration in whitening toothpastes and rinses were negligible except for Colgate Plax whitening rinse which had 1.50% hydrogen peroxide