Material and methods: Twenty extracted free of decay human teeth were randomly divided into two groups (n=10). For each tooth an individual plastic tray was fabricated based on a previously taken impression. The tray was perforated in four or five spots for the anterior and posterior teeth respectively, in order to establish a single reproductible position of the reading tip of DiagnoDent.The bleaching procedure was performed one hour each day for three consecutive days. Between the bleaching sessions the teeth were stored in artificial saliva. The first group was subjected to Opalescence 35% Gel (Ultradent Products Inc.) and the second one to a new experimental formula of 35% carbamide peroxide bleaching gel. Before and after experimental treatment the teeth covered by the plastic trays were analysed on each surface with DIAGNOdent.
Results: The measured peak values displayed on the screen before the bleaching procedures ranged between 0–11. The highest was reported in the occlusal surfaces (between 05 and 11), and the lowest in the oral or facial smooth-surfaces (between 01 and 09). After the exposure to carbamide peroxide gels, the reported values ranged between 02 and 09 for the occlusal surfaces, and between 01 and 08-09 for the axial surfaces. The fluorescence values decreased or remained stable after the bleaching procedures in the majority of the surfaces analyzed.
Conclusions: There were no important differences regarding the fluorescence values between the two groups before and after experimental bleaching. These values registered before and after bleaching remained within the same interval concerning diagnosis and therapeutical needs.