Mechanical properties of new denture base material modified with gold 　nanoparticles

Abstract

Purpose: Poly(methyl methacrylate) (PMMA) is the most commonly used material in the production of dental prostheses, and its application is often accompanied by the formation of biofilm. The aim of this work was the preparation of a PMMA/gold nanoparticles (AuNps) composite to improve the antimicrobial properties of heat-polymerised PMMA. The AuNPs were synthesised from gold (III) acetate by Ultrasonic Spray Pyrolysis (USP). In the present study, flexural strength and elastic modulus were investigated, as well as thermal conductivity, density and hardness of the PMMA/ AuNps` nanocomposite, with different concentrations of AuNps. Flexural strength and elastic modulus were measured using a three-point bending test, and surface hardness was evaluated using the Vickers hardness test. The thermal conductivity of the samples was measured using the Transient Plane Source (TPS) technique. Density was determined by the pycnometry procedure. Statistical analysis was conducted on the data obtained from the experiments. Results: The flexural strength and elastic modulus of AuNps/PMMA nanocomposites decreased for all groups containing AuNps. Thermal conductivity and density increased in all groups containing AuNps compared to the control group, but it was not significant in all groups. Vickers hardness values increased significantly with an increase in AuNps` content, with the highest value 21.45 HV obtained at 0.74 wt% of AuNps. Statistical analysis was performed by means of the SPSS 19 software package. Conclusions: Incorporation of AuNps into heat-polymerised PMMA resin led to decrease of the flexural strength and elastic modulus. At the same time, the density, thermal conductivity and hardness increased.

Investigation of the Thermal Conductivity and Flexural Strength of Polymethylmethacrylate Denture Base Material with SiC and Al2O3 Added

“…In another study, nano-sized silver particles were reported to increase the thermal conductivity of the denture base resin and could be used in the palatal region of the prosthesis [41]. Similar results were found in another recent study using gold nanoparticles [42].…”

Zinc-modified phosphate-based glass micro-filler improves Candida albicans resistance of auto-polymerized acrylic resin without altering mechanical performance

“…Similar undesired changes in mechanical properties have also been observed with the use of nanoparticles, mainly due to particle agglomeration 29 . Although silanization is believed to improve homogeneity, a matrix-compatible micro-filler to improve the properties of acrylic-based denture resins has not been found 26 , 30 .…”

“…Among these inorganic materials, zinc ions in particular have been explored as an alternative to conventional antimicrobials in dental materials 24,25 . The aforementioned additives have shown variable microbial resistance, often observed to increase with increasing concentration of additives [21][22][23]26,27 . However, the antimicrobial effects of the additives are mostly associated with compromised mechanical properties 23 .…”

Unraveling the Antibiofilm Activity of a New Nanogold Resin for Dentures and Epithesis

“…In the present study, dry AuNPs were used, which were synthesized by the USP method [ 43 ] and lyophilization for mixing into the PMMA matrix. The addition of AuNPs was also prepared with caution so as not to change the color of the PMMA, as we previously reported [ 44 ]. In this study, a decrease in biofilm formation on PMMA/AuNPs compared to conventional PMMA discs was demonstrated for the monomicrobial biofilms of C. albicans , E. coli , S. aureus and S. mitis .…”