Search

This study aimed to produce cellulose nanofiber/chitosan membranes, using essential vegetable oils (Thymus vulgaris, Anethum graveolins, Origanum vulgare, Laurus nobilisand Cominum cyminum) and a fixed vegetable oil based on Myrocarpus frondosus, for use as wound dressings. Chemical composition of the oils was evaluated by gas chromatography coupled to mass spectrometry (GC/MS), morphology was evaluated using scanning electron microscopy (SEM), and hydrophilicity was evaluated by contact angle measurements. Immunofluorescence assays were performed to evaluate the capacity of cell proliferation of the membranes. Their biocompatibility in relation to human body was ascertained by in vitro cytotoxicity tests, which were performed based on ISO 10993:2009. Each studied vegetable oil presented particular chemical characteristics and remarkable contents of 3-carene beta-linalool and caryophyllene were found. SEM images of the studied membranes demonstrated that their surface became notably rougher upon oil incorporation accompanied by decreases in contact angle, what is highly advantageous for wound dressing applications. Based on both cell proliferation and biocompatibility results, the presence of some specific compounds exerted a far more significant influence than surface roughness and wettability on the bio-curative properties. Cell proliferation capacity increased substantially with the utilization of Anethumessential oil (~35%), which was primarily attributed to the elevated presence of 3-carene, camphor, and carvone. Immunofluorescence tests further corroborated the earlier findings. In summary, within the realm of bio-curatives, Anethumessential oil has proven remarkably efficacious, standing out for its ability to enhance cell proliferation while maintaining favorable cell viability.

A photocrosslinkable gelatin methacryloyl (GelMA) hydrogel has been widely examined in regenerative engineering because of its good cell–tissue affinity and degradability in the presence of matrix metalloproteinases. A halloysite aluminosilicate nanotube (HNT) is a known reservoir for the loading and sustained delivery of therapeutics. Here, we formulate injectable chlorhexidine (CHX)-loaded nanotube-modified GelMA hydrogel that is cytocompatible and biodegradable and provides sustained release of CHX for infection ablation while displaying good biocompatibility. The effects of HNTs and CHX on hydrogel degradability and mechanical properties, as well as on the kinetics of CHX release, and on the antimicrobial efficacy against oral pathogens were systematically assessed. Cytocompatibility in stem cells from human exfoliated deciduous teeth and inflammatory response in vivousing a subcutaneous rat model were determined. Our hydrogel system, that is, (CHX)-loaded nanotube-modified GelMA showed minimum localized inflammatory responses, supporting its ability for drug delivery applications. Moreover, we showed that the incorporation of CHX-loaded nanotubes reduces the mechanical properties, increases the swelling ratio, and diminishes the degradation rate of the hydrogels. Importantly, the presence of CHX-loaded nanotubes inhibits bacterial growth with minimal cell toxicity. Our findings provide a new strategy to modify GelMA hydrogel with chlorhexidine-loaded nanotubes for clinical use as an injectable drug delivery strategy for dental infection ablation.

The objective of this study was to evaluate the effect of functionalizing a dental adhesive resin with YbF3/SiO2fillers for use as radiopacifiers. Particles of YbF3/SiO2were obtained with the high-energy mechanical milling method and characterized by both physical and chemical methods. After characterization, the particles were sieved and silanized prior to being incorporated into an adhesive resin. The stability of the particle suspension was then evaluated. After light activation, the radiopacity, degree of conversion, flexural strength and elastic modulus were determined. The dental adhesive resins with 10 and 15 wt% of filler provided satisfactory radiopacity, while flexural strength and elastic modulus were not affected. The degree of conversion was statistically lower than that of the control (p<0.05). The method used for incorporating the tested ytterbium fluoride/silicon dioxide particles at concentrations of 10 and 15 wt% was shown to be feasible for the development of a radiopaque dental adhesive system.

This study evaluated the physico-mechanical behavior and the fracture reliability of different dental resin composites indicated for the restoration of the highly mineralized enamel. The following resin composites were tested: Concept Advanced (Vigodent), Fill Magic (Vigodent), Llis (FGM), and Natural Look (DFL); Filtek Z250 (3M ESPE) was used as a universal control. All composites were fully characterized with the following tests: degree of conversion (DC), flexural strength (σ), flexural modulus (E), water sorption (WS) and solubility (SL), hardness (KMN). Scanning electron microscopy was used for morphological evaluation, whereas the topographical evaluation was carried out by profilometry (Ra) and atomic force microscopy. The color stability of the resin composites was also assessed using a digital spectrophotometer and the CIEL*a*b*system. Data were analyzed with ANOVA as well as the Weibull analysis (α= 5%). DC was similar among all composites (51.0–62.3%, p= 0.104). Llis and the control showed overall greater mechanical performance and hardness than the others. Llis and Natural Look presented lower WS and SL than the others. The control acquired smoother surface than the enamel composites. Concept Advanced and Natural Look demonstrated the greatest and lowest reliability of the study, respectively, whereas Llis showed the greatest characteristic strength (p< 0.05). Llis showed the greatest color stability of the study after 28 days of water storage (p< 0.05). In conclusion, our findings confirmed the performance of four different resin composites indicated to restore dental enamel, showing that two of them (Llis and Natural Look) can be sufficiently strong for the restoration of stress-receiving areas, such as the posterior dentition. Most of the enamel composites were as reliable as the universal control resin composite.