Search

To assess the effect of curcumin-encapsulated Pluronic® F-127 (Cur-Plu) during antimicrobial photodynamic therapy (aPDT) over duo-species biofilm of Streptococcus mutans and Candida albicans. Thermal analysis, optical absorption, and fluorescence spectroscopy were evaluated. Minimum inhibitory concentration (MIC) and minimum bactericidal/fungal concentration were obtained. The biofilms were cultured for 48 h at 37 °C and treated according to the groups: P + M + L + (photosensitizer encapsulated with Pluronic® F-127 + light); P + D + L + (photosensitizer incorporated in 1% DMSO + light); P − M + L + (no Pluronic® F-127 + light); P − D + L + (1% DMSO + light); P − L + (Milli-Q water + light); P + M + L − (photosensitizer encapsulated with Pluronic® F-127 no light); P + D + L − (photosensitizer in 1% DMSO, no light); P − M + L − (Pluronic® F-127 no light); P − D + L − (1% DMSO, no light); P − L − (Milli-Q water, no light; negative control group); CHX (0.2% chlorhexidine, positive control group); and NYS (Nystatin). Dark incubation of 5 min was used. The groups that received aPDT were irradiated by blue LED (460 nm, 15 J/cm2). Cell viability of the biofilms was performed by colony-forming units (CFU/mL) and confocal microscopy. Two-way ANOVA followed by Tukey's post hoc test was used at a significance level of 5%. P + D + L + and P + M + L + groups exhibited better log-reduction for both Candida albicans and Streptococcus mutans biofilms than P − M + L + , P − L + , and P − D + L + experimental groups. Furthermore, P + M + L + and P + D + L + showed greater reduction for Candida albicans than for Streptococcus mutans. aPDT mediated by Cur-Plu can be a potential strategy for biofilm control against duo-species biofilm of Streptococcus mutans and Candida albicans. [ABSTRACT FROM AUTHOR]

This review describes nanoparticle and dye diffusion in bacterial biofilms in the context of antimicrobial photodynamic inactivation (aPDI). aPDI requires the diffusion of a photosensitizer (Sens) into the biofilm and subsequent photoactivation of oxygen for the generation of reactive oxygen species (ROS) that inactivate microbes. Molecular diffusion in biofilms has been long investigated, whereas this review is intended to draw a logical link between diffusion in biofilms and ROS, a combination that leads to the current state of aPDI and superhydrophobic aPDI (SH‐aPDI). This review should be of interest to photochemists, photobiologists and researchers in material and antimicrobial sciences as is ties together conventional aPDI with the emerging subject of SH‐aPDI. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the antibacterial activity of a composite resin modified by 3D zinc oxide (ZnO) microstructures and to verify possible alterations on its mechanical properties. ZnO was synthesized by hydrothermal approach and characterized by X-ray diffraction (XRD), surface area by Brunauer, Emmett and Teller (BET), Fourier transform infrared spectroscopy (FTIR) and Field emission scanning electron microscopy (FESEM). The minimum inhibitory concentrations of ZnO against Streptococcus mutans, Escherichia coli, Staphylococcus aureus, and Candida albicans were determinated. The composite resin FiltekTM Z350XT (3M of Brazil) was blended with 0.2%, 0.5%, and 1% in weight of ZnO and submitted to antibacterial assay by direct contact test against S. mutans, the leading cause of dental caries and the most cariogenic oral streptococci. Additionally, it was performed compressive and diametral tensile strength tests of the modified composite resin. Microrods and hollow microrods of ZnO were obtained and its MIC values were found to be 125 μg/mL for S. mutans, 500 μg/mL for C. albicans and 62.5 μg/mL for S. aureus. For the tested concentrations, it was not found MIC against E. coli. The direct contact test showed a significant antibacterial capacity of modified composite resin ( p > 0.05 for all concentrations). The compressive and diametral tensile strength remains no changed after inclusion of microparticles ( p > 0.05 for all concentrations). The modification of the composite resin with small amounts of ZnO microparticles significantly inhibited the S. mutans growth on resin surface without significant alterations of its mechanical strength. [ABSTRACT FROM AUTHOR]

Due to increasing consumer knowledge about the health benefits associated with anthocyanin-rich foods and beverages--such as acai and blueberry juices--the growing consumption of these products should be a source of concern for dentists. Since anthocyanins are colorants that can discolor teeth and restorations, the aim of this study was to investigate the staining effects of 2 anthocyanin-rich beverages on a nanofilled composite resin. Specimens were prepared, separated into 3 groups, and immersed in either artificial saliva or 1 of the 2 staining solutions (blueberry or acai juice) at 37°C for 7 days. The color stability of the resin was significantly affected by both the storage times (P < 0.001) and the solutions (P < 0.001). The blueberry juice, which had the lowest pH level, had the greatest effect on color stability and changes in lightness of the composite resin (ΔE* = 14.71; ΔL* = -8.25; P < 0.001), followed by acai juice (ΔE* = 10.21; ΔL* = -8.77; P < 0.001) and artificial saliva (ΔE* = 1.36; ΔL* = -0.44; P < 0.001). In the present study, a nanofilled composite resin did not exhibit color stability when exposed to acai and blueberry beverages. [ABSTRACT FROM AUTHOR]

Copyright of Universidade Estadual Paulista. Revista de Odontologia is the property of Universidade Estadual Paulista. Revista de Odontologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This review describes nanoparticle and dye diffusion in bacterial biofilms in the context of antimicrobial photodynamic inactivation (aPDI). aPDI requires the diffusion of a photosensitizer (Sens) into the biofilm and subsequent photoactivation of oxygen for the generation of reactive oxygen species (ROS) that inactivate microbes. Molecular diffusion in biofilms has been long investigated, whereas this review is intended to draw a logical link between diffusion in biofilms and ROS, a combination that leads to the current state of aPDI and superhydrophobic aPDI (SH‐aPDI). This review should be of interest to photochemists, photobiologists and researchers in material and antimicrobial sciences as is ties together conventional aPDI with the emerging subject of SH‐aPDI. [ABSTRACT FROM AUTHOR]

This review describes nanoparticle and dye diffusion in bacterial biofilms in the context of antimicrobial photodynamic inactivation (aPDI). aPDI requires the diffusion of a photosensitizer (Sens) into the biofilm and subsequent photoactivation of oxygen for the generation of reactive oxygen species (ROS) that inactivate microbes. Molecular diffusion in biofilms has been long investigated, whereas this review is intended to draw a logical link between diffusion in biofilms and ROS, a combination that leads to the current state of aPDI and superhydrophobic aPDI (SH-aPDI). This review should be of interest to photochemists, photobiologists and researchers in material and antimicrobial sciences as is ties together conventional aPDI with the emerging subject of SH-aPDI., (© 2021 American Society for Photobiology.)

This article is a highlight of the paper by Choe et al. in this issue of Photochemistry and Photobiology. In that review paper, the disinfection and biomodulation outcomes promoted by antimicrobial photodynamic therapy (aPDT) on peri-implantitis infection were stated and discussed. The killing of the oral pathogens by aPDT is based on the generation of reactive oxygen species (ROS). Besides that, biomodulation can also be provided by aPDT and improve the healing and modulate the inflammatory process. Although aPDT has shown positive effects on the treatment of peri-implantitis disease mainly as a complimentary technique, the authors suggested that more and standardize clinical studies are needed to support the clinical application of aPDT for that purpose. Also, the standardization of parameters related to the light source and photosensitizers is required. In addition, nano-based materials may improve aPDT performance against oral biofilms and could increase the hopes of overcoming dental implant failures., (© 2021 American Society for Photobiology.)

This study evaluated the antibacterial activity of zinc oxide nanoparticles incorporated into self-cured glass ionomer cement (GIC) and light-cured resin-reinforced GIC on Streptococcus mutans biofilm. The GICs, Fuji II (GC America) and Fuji II LC (GC America), were incorporated with nanoparticles at concentrations of 0%, 1%, and 2% by weight, and the biofilm maturation time was one and seven days. Circular specimens of each GIC type were prepared. The antibacterial activity was evaluated by determining the number of colony forming units of S. mutans strain per milliliter. Morphology of the biofilm was analyzed by scanning electron microscopy (SEM). The data obtained for each GIC were analyzed by two-way ANOVA (α = 5%). For chemically activated GIC, no significant difference was observed in relation to the time of biofilm maturation (p = 0.744), concentration of nanoparticles (p = 0.966), and their interaction (p = 0.800). The results from analysis of GIC modified by light-polymerized resin showed that only of the maturing time significantly affected the number of adhered cells on the biofilm (p = 0.034, F = 4.778). The more mature the biofilm, higher the number of cells. SEM analysis showed no change in cell morphology in relation to the type of GIC, maturation time, and nanoparticles concentration. We conclude that the inclusion of zinc oxide nanoparticles at concentrations of 1% and 2% by weight into the GICs evaluated here, did not promote their antimicrobial activity against S. mutans., (© 2016 Wiley Periodicals, Inc.)

Due to increasing consumer knowledge about the health benefits associated with anthocyanin-rich foods and beverages-such as acai and blueberry juices-the growing consumption of these products should be a source of concern for dentists. Since anthocyanins are colorants that can discolor teeth and restorations, the aim of this study was to investigate the staining effects of 2 anthocyanin-rich beverages on a nanofilled composite resin. Specimens were prepared, separated into 3 groups, and immersed in either artificial saliva or 1 of the 2 staining solutions (blueberry or acai juice) at 37°C for 7 days. The color stability of the resin was significantly affected by both the storage times (P < 0.001) and the solutions (P < 0.001). The blueberry juice, which had the lowest pH level, had the greatest effect on color stability and changes in lightness of the composite resin (ΔE* = 14.71; ΔL* = -8.25; P < 0.001), followed by acai juice (ΔE* = 10.21; ΔL* = -8.77; P < 0.001) and artificial saliva (ΔE* = 1.36; ΔL* = -0.44; P < 0.001). In the present study, a nanofilled composite resin did not exhibit color stability when exposed to acai and blueberry beverages.

Objective: The purpose of this study was to evaluate the application of Er:YAG and Er,Cr:YSGG lasers during osteotomy in bovine bone blocks., Background Data: Er:YAG/Er,Cr:YSGG lasers for osteotomy procedures have been used to induce tissue ablation without thermal damage. However, even these lasers can induce thermal damages, which can cause a delay on the bone healing., Materials and Methods: Sixty standardized bovine bone mandible samples were divided into three groups with 20 samples each: Group 1, Bur; Group 2, Er:YAG laser; and Group 3, Er,Cr:YSGG laser. Two irradiations/cuts were made in each sample. The first was performed until the sample was completely separated into two fragments, and the time required for this procedure was recorded in seconds. The second irradiation/cut was made the same way as the first one; however, it was made partially, without separating the sample into two fragments, but rather making sulci ∼1.5-2 mm deep. Ten samples in each group were used to evaluate the surface morphology of the osteotomy by scanning electron microscopy (SEM), while the other 10 samples were submitted to descriptive histological analysis., Results: The bur was the instrument that performed the osteotomy in the shortest amount of time (p < 0.05). All the instruments caused thermal damage; however, the Er,Cr:YSGG laser was the only type that induced carbonization., Conclusions: The Er:YAG laser induced the lowest degree of thermal damage in bone tissue after osteotomy; however, a shorter clinical time was required to perform the osteotomy in the bur group.