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Spectrophotometric evaluation of the efficacy of a new in-office bleaching technique.

OBJECTIVE
To quantitatively test the hypothesis that a new paint-on bleaching gel has the potential to lighten tooth color in clinical situations and to evaluate the change of the tooth color six months after the bleaching procedure.


METHOD AND MATERIALS
Ten adult subjects requesting tooth bleaching were selected to participate in this randomized clinical trial involving a new in-office bleaching technique using VivaStyle Paint On Plus (Ivoclar Vivadent), originally designed as an over-the-counter bleaching gel. Digital images and CIE Lab spectrophotometric measurements were taken at baseline (I), after the bleaching treatment (PB), and 6 months after bleaching (6M). Differences in Lab values were tested with a repeated measures analysis of variance (ANOVA). Differences in Delta E values were tested with a factorial ANOVA.


RESULTS
Significant (P < .05) differences were detected in L, as well as in a and b values, between initial (I) and post-bleaching (PB) and between initial (I) and 6 months post-op (6M). In contrast, there was no significant difference between post-bleaching (PB) and 6 months post-op (6M).


CONCLUSION
This new bleaching technique proved to be efficient over a period of 6 months. It could be a less aggressive and more convenient alternative to traditional bleaching techniques.