The invention relates to a prepreg comprising a base part, said base part comprising fibers and a matrix, said matrix being at least partially uncured. The prepreg is characterized in that it further comprises a surface part consisting essentially of bioactive filler material, said bioactive filler material being in particle form and at least partially and at most partially embedded in said base part. The invention also relates to a composite obtainable by curing said prepreg. The invention further relates to a mineralizing sheet for treatment of hypersensitive teeth and to the use of said prepreg and composite.