Analysis of Photoreflectance and Microhardness of the Enamel in Primary Teeth Submitted to Different Bleaching Agents

Abstract

Treatment of darkened teeth in children is of great importance from an esthetic-functional point of view and for the psychoemotional development of the child. The objective of the present study was to determine the in vitro efficacy of three bleaching agents for whitening of artificially stained primary teeth. Fifty anterior primary teeth were artificially stained and then divided into three experimental groups (n = 15) submitted to bleaching treatment with 35% hydrogen peroxide gel, 35% carbamide peroxide gel, and 35% carbamide peroxide gel mixed with sodium perborate powder. The control group (n = 5) was not submitted to any bleaching treatment. Color changes were evaluated with a reflectance spectrophotometer and possible alterations in the enamel surface after bleaching were measured by Vickers microhardness testing. The data were assessed using the Student's t test. The results confirmed the bleaching action of the three agents tested. No significant difference in mean microhardness was observed between the three bleaching agents when compared to the control group.