Evaluation of the Dental Sensitivity In the initial clinical examination of patients , baseline sensitivity is measured by the vertical , horizontal drum , air jet application and probing of all teeth, so it can be compared with the sensitivity during the whitening dental.Durante whitening, patients record the presence or absence of tooth sensitivity, in a newspaper of tooth sensitivity using analog numerical scale (ENR ), with values from 0 to 4, where: 0 = no tenderness, 1 = Slight, 2 = moderate 3 = considerably and 4 = severe. And on the visual analogue scale (VAS ) with values from 0 to 10 where 0 = no sensitivity and 10 = severe. Patients mark a vertical line across the horizontal line of the scale corresponding to the intensity of tooth sensitivity. After measurement in millimeters are made with the aid of a millimeter ruler. Annex 5 and 6 values will be organized into two categories: percentage of patients with tooth sensitivity at some time during treatment ( absolute risk sensitivity ) and intensity of tooth sensitivity.