Tribological, microhardness and color stability properties of a heat-cured acrylic resin denture base after reinforcement with different types of nanofiller particles.

Abstract

Polymethyl methacrylate (PMMA) is not an ideal material in all aspects, as it has poor mechanical and antimicrobial properties. The enhancement of the mechanical and physical features of PMMA-based material is highly required. The present study aimed to estimate the effect of adding different types of nanoparticle (NP) materials on the mechanical and physical features of heat-cured acrylic resin denture base material. A total of 120 samples were divided into 4 groups: the control group; the 5 wt% ZrO2 NPs group; the 5 wt% TiO2 NPs group; and the 5 wt% Ag NPs group. Each one was subdivided into 3 groups according to the test performed: the microhardness test; the abrasive wear test; and the color stability test. Then, the results of these tests were evaluated. The maximum mean value for the microhardness test was observed in the group treated with the addition of 5 wt% Ag NPs, followed by the 5 wt% ZrO2 NPs group, and finally the 5 wt% TiO2 NPs group. The lowest mean microhardness value was recorded for the control group. The maximum mean value for the abrasive wear test was attributed to the control group and the lowest mean value was related to the 5 wt% Ag NPs group. The maximum color change was noted in the 5 wt% Ag NPs group, followed by the 5 wt% ZrO2 NPs and 5 wt% TiO2 NPs groups. The lowest mean value for the color change was found in the control group. There was an increase in hardness and wear resistance in the group treated by adding 5 wt% Ag NPs, and the control group had the best color stability, followed by the 5 wt% TiO2 NPs group. However, a detrimental effect on color stability was observed when 5 wt% Ag NPs was added.