A composition for delivery of an oral care substance to a dental surface upon application of the composition thereto is a flexible film comprising the oral care substance dispersed in a film-forming effective amount of a polymeric matrix having a hydrophilic component, e.g., vinylpyrrolidone (VP), and a hydrophobic component, e.g., vinyl acetate (VA), in a weight ratio selected such that the film is substantially dissolvable in saliva in a period of time effective for delivery of the oral care substance. The polymeric matrix illustratively comprises a poly(VP/VA) copolymer having a VP/VA weight ratio of about 90:10 to about 10:90.