A dissolving strip for tooth whitening the strip having at least a first tooth contacting layer and a second outer layer. The first tooth contacting layer has a solid tooth whitening active in an amount which reacts within a predetermined time when placed on a tooth. The second outer layer has a blend of polymers having different molecular weights; the blend of polymers being selected to dissolve after the predetermined time has elapsed. The outer layer contains the tooth whitening active on said tooth until the active is substantially used up. A method of forming a dissolving tooth whitening strip is also provided, in which the outer layer is formed on a backing layer followed by the inner layer being formed on the outer layer.