Raman spectroscopy analysis of dental enamel treated with whitening product – Influence of saliva in the remineralization

In this work we present the analysis of dental enamel treated with an over-the-counter whitening product, bought in e-commerce at a very low cost, used without medical supervision in an abusive manner, in order to evaluate its demineralization action. Moreover, we studied the influence of renewal or non-renewal of saliva so- lution in which the specimens were stored throughout the study. The Degree of Demineralization was determined through the evaluation of the PO34− symmetric stretching band (~959 cm−1) in Raman spectra of the specimens in different days during the course of the study. Results showed that a maximum of demineralization occurred between days 27 and 34 of application. Titration of the whitening product revealed a content of hydrogen peroxide 170-fold higher than what is allowed in Europe, according with legislation. Despite this extreme concentration of hydrogen peroxide, the deminerali- zation was not as great as could be expected suggesting an important role of the pH of the solution in this demin- eralization mechanism.