Effect of application of desensitizers before bleaching on change of tooth shade.

The aim of this in vitro study was to evaluate the effects of desensitizer pre-treatment on in-office bleaching using an artificial discoloration tooth model. The stained specimens were divided into four groups (n=10); without application (Control group), Shield Force plus (SF group), UltraEz (UE group) and Teeth Mate AP paste (TM group) applied before bleaching. Each group was bleached by an in-office bleaching agent. The CIE Lab* values were measured by a colorimeter before and after ten consecutive bleaching treatments and the color difference (∆E) was calculated. There was no statistical difference among ∆E values of Control, UE, and TM groups (p>0.05). There was a significant difference between SF and Control groups (p<0.001). It was concluded that application of TM and UE did not affect the change of tooth shade while SF application impeded the bleaching effect.