Kinetic release of hydrogen peroxide from different whitening products.
The objective of this in vitro study was to evaluate the kinetics of hydrogen peroxide (HP) release from five different bleaching products: VivaStyle® 10% fitted tray gel, VivaStyle® 30% in-office bleaching gel, VivaStyle® Paint-On Plus paint-on bleaching varnish, Opalescence PF® 10% carbamide peroxide gel and Trèswhite Supreme 10% HP gel. Each product was firstly titrated for its HP content by a described method. HP release kinetics was assessed by a modified spectrophotometric technique. One sample t test was performed to test for differences between the manufacturers' claimed HP concentrations and the titrated HP content in the whitening products. Analysis of variance plus Tamhane's post hoc tests and Pearson correlation analysis were used as appropriate. Values of P < 0.05 were taken as significant. Titrated HP revealed an increased content when compared to the manufacturer's specifications for all the products tested (P < 0.05), although only products from one manufacturer produced significantly higher results. All products presented a significant (P < 0.05) and sustained release of HP. However, the product with paint-on cellulose-based matrix resulted in significantly (P < 0.05) faster kinetics when compared to other products tested. These results are consistent with manufacturers' reduced recommended application times. The results of this study suggest that modifying the matrix composition may be a viable alternative to HP concentration increase, since this may result in faster release kinetics without exposure to high HP concentrations.
University of Lisbon, Lisbon, Portugal. duartemd@yahoo.co.uk
Duarte Nuno
DN
da Silva Marques
Joao Miguel
JM
Silveira
Joana Rita
JR
Marques
Joao Almeida
JA
Amaral
Nuno Marques
NM
Guilherme
António Duarte
AD
da Mata
D000704:Analysis of Variance; D006861:Hydrogen Peroxide / Q000032:analysis*; D007700:Kinetics; D013053:Spectrophotometry; D018709:Statistics, Nonparametric; D017186:Titrimetry; D058205:Tooth Bleaching Agents / Q000737:chemistry*
D058205:Tooth Bleaching Agents; D006861:Hydrogen Peroxide