A method of applying a dental sealant composition to a surface of a tooth or dental restoration is provided. The method involves the steps of providing a sealant composition comprising a filler system of colloidal silica particles dispersed within a methacrylate or acrylate resin and a polymerization system capable of being activated by light. The nanometer-sized silica particles have an average particle size of about 10 nm to about 100 nm. The composition is irradiated with light, preferably blue visible light having a wavelength in the range of about 400 to about 500 nm, so that it hardens. The hardened sealants provide a strong, non-tacky surface finish over a dental restoration or tooth.