EVALUATION OF THE MANUAL MIXING EFFECTIVENESS OF VINYLPOLYSILOXANE IMPRESSION MATERIALS
In the clinical practice of prosthodontic dentistry, vinyl polysiloxane impression materials of high viscosity are widely and successfully used. The base layer of these materials is kneaded manually, and the mixing quality control of the material is ensured due to the differences in the colors of the catalyst and base masses of the material and is carried out by the doctor subjectively. The color shade obtained by mixing the impression material is close to the base mass color of the material, which does not allow an accurate mixing quality assessment. Purpose: objectification of the mixing efficiency evaluation of vinyl polysiloxane impression materials. Five high viscosity vinyl polysiloxane materials with different base masses colors were included in the study. Base, catalyst and manually mixed masses samples were made for each of the materials to compare their color characteristics. Evaluation of the manual mixing control of studied materials was carried out by analyzing the color differences between the mixed impression material with the base and catalyst masses colors, as well as the color variability degree of the base mass after mixing with the catalyst mass from photographs taken under different lighting conditions. The color distance and base mass color variability at good, moderate and poor illumination. According to the proposed method of objectifying the assessment of the impression materials mixing, Bisico S1 SOFT has the best indicator of the base mass color variability, which provides good mixing control efficiency. The lowest base mass color variability was found for Express STD and Elite HD+. Bisioco S1 and Detaseal impression materials are average in this indicator, and their manual mixing efficiency can also be easily controlled.