[The color analysis of nanocomposite material before and after exposure to whitening toothpastes using a portable spectrophotometer].

PURPOSE: To determine the effect of whitening toothpastes on the color of a nanocomposite material using a spectrophotometer. MATERIAL AND METHODS: The study involved 50 samples from nanocomposite restoration material which were exposed under laboratory conditions to brushing with one of 4 types of toothpastes (control with no bleaching agents, peroxide paste with carbamide, abrasive and enzyme-based pastes). Using the parameters a, b and L obtained by spectrophotometry, delta E (DeltaE) value was calculated. To determine the maximum and minimum A posteriori comparisons by the Scheffe method were used to influence the delta E parameter after exposure to the pastes. Oxygen-containing paste (OZPP) had a maximum effect on the increase of the DeltaE parameter, DeltaE=1.03 comparing to DeltaE=0.20 in control toothpaste. The isolated effect of a toothbrush resulted in a large change in the parameter DeltaE, compared to the effect of a controls. However, the DeltaE does not indicate the clarification of the material, but only a change in color relative to the initial measurement. As a result of spectrophotometry and statistical data processing, it was found that all pastes had a sufficient effect on the color change for the device to determine, but this change was not noticeable to the human eye.