Introduction: Dentin hypersensitivity derived from exposed roots has a high prevalence. By occluding exposed dentinal tubules it is possible to achieve a relief since avoids displacement of intratubular fluid. Objectives: To evaluate which of the different dentinal sample preparation methods exposed to the nanoXIM 9% solution achieves better Scanning Electron Microscope (SEM) microphotographs quality preserving the nanoXIM solution hydroxyapatite in the dentinal tubule lumen. Materials and Methods: Six dentin specimens were obtained from human teeth and submerged in nanoXIM 9% study dentifrice solution for 5 days. The six specimens received three different treatments: a surface sealant was added to the dentinal surface for 2 specimens ("EasyGlaze" Group), nail varnish was added to other 2 specimens ("Varnish" Group) and for the other 2 specimens, nothing was added ("Sem Nada" Group). The specimens were observed at the Scanning Electron Microscope (SEM). Results: The "Sem Nada" sample was the only one where was possible to observe clearly the occluded dentinal tubules with the nanoXIM solution. In the "EasyGlaze" group the hidrophobic resin originated tags which penetrate the tubules and coated the dentin, jeopardizing the SEM observation. The "Com Verniz" sample originated na amorphous layer which also jeopardized a correct dentin observation. Conclusions: In the "Sem Nada" Group the pretended results where achieved. The nanoXIM 9% solution seems to be effective in the tubular occlusion. Clinical Implications: By occluding successfully the dentinal tubules, the hydroxyapatite solution may be effective in reducing the dentinal sensitivity. Keywords: Dentinal sensitivity, Dentine Tubule occlusion, Hydroxyapatite, Dentin, Scanning Electon Microscopy, Desensitizing Dentrifice