The present invention relates to compositions and methods of whitening teethof a subject in need thereof, by applying a safe and effective amount of acomposition to a plurality of teeth, the composition comprising: a. a safe andeffective amount of a bleaching agent； b. a safe and effective amount of awater insoluble solid phase； c. a safe and effective amount of a water solubleliquid phase； wherein the ratio of the water insoluble solid phase to watersoluble liquid phase is from about 1:4 to about 4:1； wherein the compositionis applied for a sufficient period of time to achieve whitening； and whereinin one embodiment the composition has a Whitening Index of from about 0.5 toabout 4. The composition comprises a hydrophobically modified polymer. Thepresent invention also relates to a delivery system comprising the presentcompositions used with an integral carrier, e.g. a strip material, dental trayor sponge material.
