We present a detailed study of the nonresonant third-order ultrafast response of TiO(2) nanostructured films, combining a classical heterodyned optical Kerr effect experiment, with two polarization selective Kerr techniques, based on transient lensing and phase modulation effects. The complementarity of these techniques is highlighted and demonstrated with calculations. Different aspects of the experimental results are addressed in detail and, finally, the possibilities of performing experiments on liquid dynamics in the pores of TiO(2) films, are discussed in the light of the present results.