Antimicrobial and mechanical acrylic resin properties with silver particles obtained from Fusarium oxysporum

Abstract

<p><strong>Objective: </strong>This study evaluated the effects of the incorporation of silver nanoparticles (AgNPs) obtained from <em>Fusarium oxysporum</em> on heat-activated acrylic resin (HAAR) and their influence on resin’s surface roughness, hardness, color alteration and antimicrobial capacity against <em>Candida albicans</em>. <strong>Material and Methods:</strong> For this, 50 discs of HAAR (2x5 mm) were produced and divided into three groups, Control: HAAR; Ag1: HAAR plus 0.539 mg of AgNPs; and Ag2: HAAR plus 1.1 mg of AgNPs. Knopp hardness (HK), surface roughness (Ra and Rz) and color alteration according to the CIE Lab were measured. Specimens were then evaluated <em>in vitro</em> with regard to <em>C. albicans</em> biofilm formation through formed colony count (CFU/mL). Scanning Electron Microscopy (SEM) and Atomic force microscopy (AFM) analyses were performed. <strong>Results:<em> </em></strong>The addition of AgNPs of both concentrations changed Ra, Rz and HK significantly. There was statistically significant difference for L (p=0.00); a*(p=0.00) and b*(p=0.00) parameters. There were no differences between Ag1 and Ag2 biofilm formation, but the comparison of both with the control group presented a significant reduction (p=0.0091) on biofilm formation. SEM and AFM images showed no signs of NPs clustering. <strong>Conclusion:</strong> It can be concluded tha AgNPs incorporation in HAAR was effective in reducing <em>C. albicans</em> activity, with a slight change in color and hardness of the material, being effective therefore, in regions such as the dental prostheses palate, which have lesser aesthetic appeal.</p><p><strong>Keywords</strong></p><p>Acrylic resins; Silver; Antimicrobial agents.</p>

Applications of Silver Nanoparticles in Dentistry: Advances and Technological Innovation

“…As an example, the addition of 1% silver graphene improved the mechanical properties of PMMA [ 68 ], including the increase of their viscoelastic properties [ 84 ]. The addition of AgNPs to PMMA decreased surface roughness and reduced C. albicans viability due to the reduced ability of the fungus to adhere and colonize dental prostheses [ 35 , 53 , 70 , 73 ]. In disagreement, other researchers have reported that AgNP did not inhibit C. albicans growth [ 32 ], but when associated with quaternary ammonium dimethacrylate (QADM), they presented antibiofilm activity [ 52 ].…”

“…On the other hand, the addition of AgNPs caused color changes in prosthetic devices [ 16 , 53 , 70 , 84 ]. Color change was attributed to the plasmatic effect of AgNP through electronic propagation as an electromagnetic wave in the visible light spectrum [ 16 , 29 ].…”

Effect of silver-coated silica nanoparticles on the thermal conductivity of thermally activated acrylic resin

“…These materials can reproduce the oral surface in detail and can be easily relined. However, in contrast to these advantages, large difficulties are encountered with their use due to undesirable properties, such as a high coefficient of thermal expansion, low thermal conductivity, low elasticity coefficient, low impact, and fatigue strength [4][5][6][7]. In particular, the distinct disadvantage of polymethylmethacrylate (PMMA) is its low thermal conductivity [8,9].…”