Objectives:The aim of the present work was to determine the actual concentration of HP in five commercially available bleaching formulations and compare this to the value claimed for the product.
Method:An iodine/thiosulphate titration was used to determine the concentration of HP in 5 different bleaching gels namely Quickstart Bleaching nominally 35% carbamide peroxide (CP), Ultradent Bleaching nominally 10% CP, Polaoffice nominally 35% HP, Optident Bleaching nominally 10% CP and Dr.George's bleaching system where the percentage HP was not stipulated.
Results:The results ( n=5 ) showed a high degree of repeatability and the mean measured value was very close to the nominal manufacturer's specification. The results for Dr.George's bleaching system gave a mean value of 4.11 (S.D. 0.07) indicating that it is a 15% CP solution.
Conclusions:The commercial preparations evaluated in this study contained or generated HP at a level close to that reported in the formulation. This data is valuable in that by both confirming the quality of commercial preparations we may now develop HP based in vitro model systems for subsequent investigations of tooth bleaching agents.