Color stability and surface roughness of chitosan- and nanodiamond-modified bisacrylic resin

Abstract

The aim of this study is to evaluate the effect of chitosan or nanodiamond incorporation on the color stability and surface roughness of a bisacrylic resin subjected to artificial aging. Four bisacrylic resins were evaluated, namely, control, chitosan-modified material, nanodiamond-modified material, and chitosan-nanodiamond-modified material. Twenty-four specimens were prepared for each material. The surface roughness was determined using a profilometer with a cutoff of 0.25 mm. The baseline color was measured according to the CIE L*a*b* system using a reflectance spectrophotometer. After these tests, the specimens were individually immersed in cola soft drink, red wine, or distilled water (n = 8) for 28 days. After the aging, the surface roughness and final color were re-evaluated. The color stability was determined using the difference between the coordinates obtained before and after the aging process. The data on roughness and color change were evaluated using ANOVA and the Tukey test (α = 0.05). The results show that the incorporation of nanodiamonds and chitosan into a bisacrylic resin provided a better color stability to the materials (p = 0.007). The storage in red wine resulted in a higher variation in the surface roughness values, especially when only the nanodiamond was incorporated to the material (p < 0.05). The incorporation of both chitosan and nanodiamonds are promising in providing an improvement in the properties of the bisacrylic resin when they are simultaneously incorporated in the product.

Lignin Nanoparticles Support Lipase‐Tyrosinase Enzymatic Cascade in the Synthesis of Lipophilic Hydroxytyrosol Ester Derivatives

“…Field emission scanning electron microscopy (FE-SEM) analysis of Catalyst I and Catalyst II (Figure 1) showed nanoparticles with regular spherical shape characterized, in the case of Catalyst II, by the typical corona-like structural motif associated to the presence of Con A (Figure 1, panel B) (FE-SEM analysis of OLNPs are reported in Supporting Information #1). [44] This different morphology was appreciable from that observed for Catalyst I, in which case roughly aggregates of small clumps, typical of CH, [45] were present on the surface of the nanoparticles (Figure 1, panel A).…”

Nanoparticles of Lignins and Saccharides from Fishery Wastes as Sustainable UV-Shielding, Antioxidant, and Antimicrobial Biofillers

“…Nanoparticles showed a regular spherical shape with roughly aggregated small clumps on the surface, being more pronounced in the case of samples bearing CH with a high value of DD (Figure , Panel A; the second and third columns, respectively). These clumps are the fingerprint of the saccharide − and were not visible on the surface of nanoparticles produced from lignin alone (Figure , Panel A; first column). In addition, the presence of high DD chitosan ( CH5/OLNPs and CH1/OLNPs , respectively) afforded nanoparticles with a lower aggregation state than CH4/OLNPs .…”

Evaluation of compressive strength, color stability, and antimicrobial action of chitosan-modified temporary crowns

“…They claimed that chitosan in acrylic resins acted as an impurity in the PMMA matrix, which reduced its flexural strength. [ 9 ] According to[ 9 10 ] chitosan may have a negative impact on polymerization conversion and result in an increase in the amount of residual monomer which acts as a plasticizer further decreasing compressive strength.…”

“…[ 8 ] Any changes to the composition must enhance or at least keep the original material's esthetic qualities and surface characteristics from declining. [ 9 ] The goal of this research is to see how additives such as chitosan affect the strength, color stability, and antibacterial action of PMMA-based temporary restorations. The null hypothesis was that the compressive strength, color stability, and antimicrobial activity of chitosan-modified PMMA would have no statistically different mean values compared to control PMMA.…”