[Comparison of pH in teeth bleaching systems]

The most relevant parameters of teeth bleaching systems are their pH value and the concentration of the peroxide compound as the basic active component.

The aim of this study was to examine the pH parameter of available bleaching systems to predict the possible risk of enamel demineralization and the occurrence of increased sensitivity of hard dental tissues during and after clinical and home bleaching procedures. A total of 26 different materials were studied in the work.

The studies were carried out on samples of bleaching systems that have a valid expiration date, proper storage and transportation in the Testing Laboratory Center of the Federal Institution of Healthcare "Center for Hygiene and Epidemiology" in Moscow in the period 2022-2024. For measurements, a laboratory pH meter "Anion 4100" was used, which allows measuring the activity of hydrogen ions (pH) and the oxidation-reduction potential Eh (mV). Measurements for each sample taken by us were made at the initial pH, after mixing the system components together, and also after the application time recommended by the manufacturer, in order to understand the stability of the pH change during the procedure.

The results of testing the bleaching systems presented on the Russian market showed that their pH level was determined within the normal range, no critical values were identified.

In clinical practice, the technical parameters of peroxide gels are critically important, first of all, acidity, and secondly, concentration, which will significantly affect the patient's comfort during the procedure and the occurrence of sensitivity of hard dental tissues. Obviously, the lower the concentration of the peroxide compound and the lower its acidity, the higher the chances of comfortable and painless clinical bleaching.