A swift, easy and cheap protocol to evaluate the tooth bleaching in vitro

This study aims to develop a protocol that optimizes in vitro dental bleaching procedures in a cheap, fast and accessible manner.

18 bovine incisors were cut and polished in enamel/dentin and submitted to staining in coffee solution during 72 hours. After the standardization and staining of the enamel surfaces, three groups (n = 6) were formed to receive three different gels, WHITENESS (commercial gel); H2O2 - 5% (manipulated gel); CARBOPOL GEL (manipulated gel and without H2O2). The color of the enamel surfaces was evaluated using digital images, obtained with digital camera and controlled luminosity, before and after staining, as well as after each bleaching step.

The average bleaching after 48 hours of procedure was: WHITENESS with 13.6 (± 1.2); H2O2 (5%) with 9.8 (± 1.4) and CARBOPOL GEL with 2.9 (± 0.6). After 72 hours, WHITENESS presented a mean of 15.8 (± 0.7), the H2O2 group (5%) 14.4 (± 1.5) and CARBOPOL GEL 4.6 (± 1.0). After completing 96 hours of whitening, WHITENESS presented an average of 18.3 (± 0.8), H2O2 (5%) 16.7 (± 1.4) and CARBOPOL GEL 7.3 (± 0.8). Our data demonstrated that the protocol development for us can be used to evaluate dental bleaching in a short time, with 96 hours already was possible to detect significant differences, when compared with the longer times of experimental dental bleaching.

The proposed protocol guarantees statistically significant results in 96 hours, confirming the efficacy, cheapness, viability and practicality of the protocol developed in this study. Key words:Enamel, color, aesthetics.