Dental bleaching systems that include a bleaching component and a neutralizing component which, when mixed together, yield a mixed composition having a desired bleaching activity and gel properties. The bleaching composition includes a suitable bleaching agent, such as aqueous hydrogen peroxide, in a concentration of about 3 % to about 95 % by weight of the bleaching composition component. The neutralizing component includes a strong particulate base mixed with a polymeric thickening agent. The neutralizing component is substantially water-free to prevent destruction of the gelling capability of the thickening agent by the base prior to formation of the mixed composition. The particulate base may include oxides, hydroxides or carbonates of alkali metals or alkaline earth metals. Maintaining the bleaching agent and neutralizing agent in separate components provides increased stability of both the bleaching agent and gelling (thickening) agent during storage and transport.
