An agent for protection of tooth surfaces, in conjunction with conventional bleaching methods, by biomimetic deposition of fluorapatite, containing A at least one preformulated 50-1000 μm thick gel film A, containing A1 at least one gel former, A2 water or a mixture of water and an organic solvent, A3 phosphate or hydrogen phosphate ions, A4 optionally fluoride, A5 optionally at least one amino acid, A6 optionally one carboxylic acid or a buffer system for a pH value from 4 to 7. B at least one 50 μm to 5 mm thick gel film B, containing B1 at least one gel former, B2 water, B3 calcium ions Ca2+.