Journal of Applied Biomaterials & Functional Materials最新文献

The use of hydraulic calcium silicate cements (HCSCs) is essential for vital pulp therapies (VPT). However, their high cost restricts access in low- and middle-income countries, preventing the widespread benefits of VPT. This study aimed to evaluate four previously developed and characterized low-cost HCSC prototypes by examining their biological properties, specifically the rat connective tissue response after implantation and antimicrobial activity against five strains of interest. Additionally, their compressive strength, bond strength, and microhardness, which are critical mechanical properties of materials used in VPT, were assessed. All HCSCs caused an inflammatory reaction, which decreased over time in all cases, with most reactions categorized as mild. When comparing the number of inflammatory cells at each time point, no significant differences were observed between the HCSCs and those compared to MTA Angelus. Regarding the fibrous capsule, its thickness gradually decreased, and all capsules ultimately had a thickness with no significant difference compared to those formed in the empty control group. No significant differences in antimicrobial activity were seen among the four prototypes, as they exhibited similar performance against the five tested strains. However, some prototypes showed significantly better performance compared to MTA Angelus. Concerning mechanical properties, most prototypes exhibited substantially higher compressive strength than MTA Angelus, with a gradual increase over time-though this increase was not always significant. Additionally, no prototype demonstrated significant differences in bond strength compared to each other or MTA Angelus. Microhardness also increased over time, with significant differences observed when comparing prototypes to MTA Angelus at each time point. These findings, along with previously reported data on their microstructure, composition, and physical properties, support the potential clinical use of these prototypes. However, further research is needed to evaluate their effectiveness in clinical settings.

In the present study, polylactic acid (PLA) was incorporated to ameliorate the rheological and mechanical properties of chitosan (CS)-based hydrogels. A novel injectable chitosan/polylactic acid (CS/PLA) nanofiber composite hydrogel, fabricated via the electrospinning technique, was developed for the sealing and repair of fistulas, thereby functioning as an innovative biomaterial for the treatment of tracheoesophageal fistula (TEF). Experimental data demonstrated that the CS/PLA composite nanofiber hydrogel exhibits superior mechanical properties, favorable rheological behavior, and prominent antimicrobial activity. At the optimal ratio, the compressive strength and tensile strength of CS/PLA composite nanofiber hydrogel is 43.7 MPa and 1.38 MPa, and the degradation rate is 68.9% after 10 days. Meanwhile, the antibacterial rates against E. coli and S. aureus CS/PLA composite nanofiber hydrogel reached 82.6% and 76.3%, respectively. In vitro experiments were performed to assess the biocompatibility and cell proliferation capacity of the composite hydrogel. The results revealed that the CS/PLA composite nanofiber hydrogel can effectively facilitate the proliferation and migration of target cells, while simultaneously exhibiting favorable biocompatibility. These findings indicate that the CS/PLA composite nanofiber hydrogel possesses considerable application potential in TEF repair, thereby offering an innovative and efficient biomaterial option for clinical intervention of TEF.

Laminin-521 (LN521) is a crucial adhesion protein found in natural stem cell niches and plays an important role in maintaining human pluripotent stem cell (PSC) properties. This study aimed to investigate the effects of LN521 on human umbilical cord-derived mesenchymal stem cell (UC-MSC) characteristics in Serum-free and Xeno-free culture conditions as a step toward clinical application. In our experiment isolated UC-MSC via explant method were expanded as a homogeneous monolayer and morphologically, presented typical MSC-like morphology (spindle-shaped) from passage three to six when cultured on either LN521 or CELLstart™. Almost, 90% confluency was reached after 4 days of culture with an EI of approximately 11.2 with no statistically significant differences on LN521 and CELLstart™ in all six passages. Phenotypic characterization of UC-MSC cultured on LN521 or CELLstart™ using flow cytometry, along with the expression of the same biomarkers in gene level analyzed by quantitative reversed transcription revealed identical CD73, CD90, CD105, CD34, CD45, CD19, CD14, and HLA-DR expression pattern at passages three and six in both LN521 and CELLstart™. Moreover, UC-MSC cultured in the presence of LN521 and CELLstart™ showed the same adipogenesis, chondrogenesis and osteogenesis differentiation potential, and normal chromosome structure highlighting genetic stability. Ultimately, LN521 is comparable to CELLstart™ in supporting UC-MSC expansion and maintaining their characteristics in serum-free and xeno-free culture conditions.

Oligopeptides, composed of 2-10 amino acid residues, are protein fragments with unique structural characteristics, including small molecular size, high biocompatibility, and modifiable functional groups. These features endow oligopeptides with excellent permeability, safety, and versatile biological activities, making them widely applicable in disease treatment, drug delivery, and skincare. In particular, oligopeptides have emerged as advanced ingredients in skincare, offering anti-aging, anti-wrinkle, and whitening effects by regulating key biological processes such as collagen synthesis, antioxidant defense, and melanin production. This review comprehensively discusses the structural properties, functional mechanisms, and diverse applications of oligopeptides and their derivatives, highlighting their potential in skin regeneration, rejuvenation, and anti-aging medicine. By providing insights into the latest advancements, this review aims to serve as a valuable reference for future research and development in oligopeptide-based therapeutics and skincare innovations.

Aim: This study aimed to assess the time-dependent water sorption, solubility and hygroscopic expansion of experimental resin composites modified with three different types of ion-leachable glasses (ILGs): 45S5 Bioglass (BG), Fluoride-containing glass (F9) and Experimental fluoride-phosphate glass (F9X), incorporated in varying weight percentages (5%, 10% and 15%).

Materials and methods: A 50:50 Bis-GMA/TEGDMA-based resin matrix was loaded with each ILG type in 5, 10 and 15 wt% and compared against a control without filler. Disc-shaped specimens (n = 3 per group; total = 39) were fabricated using a stainless-steel mould and cured using an LED light-curing unit (1200 mW/cm², 20 s per side). The water sorption and solubility were evaluated using a modified ISO 4049 protocol over a 12-week immersion period in distilled water at 37°C, followed by an 8-week desorption phase. Hygroscopic expansion was evaluated through volume change using a digital micrometre. Data were statistically analysed using one-way ANOVA and Tukey's post-hoc test.

Results: All ILG-containing composites showed significantly increased water sorption compared to the control, with the BG-15 group demonstrating the highest sorption (3.37% ± 0.09) and expansion. Solubility increased with ILG concentration, especially in the BG and F9X groups. Hygroscopic expansion correlated positively with water uptake. No significant changes were observed in specimen mass after desorption in low filler groups.

Conclusion: The incorporation of ILGs into resin composites significantly altered their water uptake and dimensional stability. While these effects could compromise long-term mechanical properties, the resulting hygroscopic expansion may aid in reducing microgaps and secondary caries at restoration margins. Veneering ILG-containing composites with conventional materials is recommended to limit degradation. These findings contribute novel insights into time-dependent dimensional behaviour of bioactive composites.

For millennia, aloe vera (AV) and eucalyptus oil (EO) have been recognized as natural sources of healing and have been utilized for medicinal purposes in the realm of health. As an attempt to treat pressure sores, AV and eucalyptus oil were added as supplements to biocompatible and biodegradable poly (ethylene oxide) (PEO) polymer to synthesize nano and micro fibrous wound dressings by the electrospinning process. Additive solubility in polymeric matrix is the key parameter to achieve the synthesis of homogeneous fibers with controlled release of therapeutic oils, cure and humidity; therefore, lecithin as herbal (soybean) based emulsifier was used to control additive/polymer solubility. In this study, fibrous dressing in mat form with antioxidant activity was successfully obtained with the addition of natural AV and EO in PEO polymer solutions through electrospinning technique. Subsequently, the synthesized fibers were examined via scanning electron microscopy (SEM), thermogravimetric analysis (TGA), moisture absorption and UV-Vis spectroscopy. SEM imaging demonstrated the formation of randomly-oriented and beadless fibers with size of 0.48 ± 0.23 µm out of PEO/AV/EO/Lecithin blend and also with the addition of lecithin, fiber thicknesses were observed to be increasing. Moisture absorption analysis revealed that the weight of fibrous mat was affected by the humidity of the ambient environment. Relative humidity for 7 days ranged between 32% and 37% and it was observed that lecithin content increased the moisture retention rate by 50%. Uv-Vis results suggested that a more regular performance has been achieved with lecithin being involved in terms of timely manner changes; therefore, the contrast of samples between hours and days became more distinctive. PEO/AV/EO/Lecithin nanofiber also indicated antibacterial ability against Escherichia coli with approximately 18.5 mm diameter of inhibition. This research proves that the potential for developing biocompatible wound dressings with long-lasting moisture to the wound is possible through the use of these natural healing agents made homogeneously distributed through structure by the use of emulsifier.

Alternative calcium phosphates are strong candidates as tooth-whitening to mitigate the adverse effects of hydrogen peroxide (HP). This study examines changes in the color and chemical structure of human enamel induced by a biomimetic calcium phosphate-based bleaching ceramic derived from chicken eggshell, known as the experimental remineralizing Substance (ERS). Forty human molars were assigned to four groups: G1: storage group; G2: treated with 35% HP; G3: treated with ERSs; and G4: treated with HP followed by ers. CIE color coordinates (L*, a*, b*) were recorded before and after treatment using a dental spectrophotometer to calculate color differences (ΔE*_ab, ΔE₀₀) and the whiteness index$\left(W{I}_D\right)$ which were later compared with previously established perceptibility (PT) and acceptability (AT) thresholds. After each treatment, enamel surface powders from each specimen were analyzed using attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray diffraction (XRD). Statistical analyses included one-way ANOVA and simple linear regression for color measurements, as well as one-way ANOVA, Shapiro-Wilk, Kruskal-Wallis, and Holm-Bonferroni tests for chemical composition. The results indicated a significant decrease in L* (p = 0.01) and b* (p = 0.03) values in G3. The highest mean values of ∆E*_ab and ΔE₀₀ (p ⩽ 0.05) exceeded PT and AT indicating good effectiveness. ATR-FTIR analysis revealed that certain phosphate bands in G3 remained unchanged compared to G1 and G2. Additionally, carbonate substitution at the A and B-positions was reduced, and the degree of mineralization increased compared to G2. XRD patterns showed diffraction peaks linked to hydroxyapatite crystals in all experimental groups. All treatments reduced crystallite size, and this effect was not reversed in G3. Thus, this study demonstrates that ERS achieved a superior whitening effect compared to HP, without altering the chemical composition or crystalline structure of human enamel. These findings suggest the potential of using ERS as a safer alternative to conventional peroxide-based whitening agents.

The use of plant extracts for the synthesis of metal nanoparticles represents a promising direction in nanotechnology due to the high environmental friendliness and cost-effectiveness of the method. In this study, green synthesis of silver nanoparticles was carried out using Hibiscus sabdariffa and Aloe vera extracts. The synthesis was conducted by reaction between the extracts with a silver nitrate solution, leading to the formation of silver nanoparticles. The synthesized nanoparticles were identified using UV-visible spectroscopy, scanning electron microscopy, particle size determination, and X-ray diffraction (XRD) analysis. The UV spectra exhibited characteristic absorption in the range of 350-450 nm, confirming the presence of silver nanoparticles, while XRD analysis determined an average particle size of 6.11 nm. The size analysis demonstrated the stability of the nanoparticles over time and their retention within the nanometer range. Comparative antibacterial tests demonstrated that AgNPs synthesized using H. sabdariffa extract showed higher inhibitory activity against E. coli and S. saprophyticus compared to those produced with A. vera extract. The obtained results confirm that biogenic synthesis using plant extracts is an environmentally safe and highly efficient alternative to conventional chemical methods, offering promising applications in biomedicine, catalysis, and other high-tech fields.

In a variety of applications, such as sensing, vibration control, wind turbine blades, automobile panels, submersible vehicles, and structural health monitoring, smart structures which are made up of laminated composite plates sandwiched between two piezoelectric layers are used. The issue of fractional derivatives for delaminated and multilayered piezoelectric composite plate supported on a viscoelastic foundation's free vibration response has been tackled in this work. A system of differential quadrature and a perturbation method are used to derive and solve the governing equations. Four form functions, the Lagrange interpolation polynomial, the Cardinal Sine function, the Delta Lagrange, and the Regularized Shannon kernel are used in this study to provide new DQM approaches. A numerical system is suggested and tested under a range of support circumstances to determine its accuracy and efficiency, which relies on prior enabling more accurate predictions critical for the design and deployment of intelligent structural systems.

Orthopedic implant-associated infections, primarily caused by biofilm-forming Staphylococcus aureus, pose significant clinical challenges. These infections often lead to implant failure, prolonged antibiotic treatments, and an increased risk of revision surgeries, emphasizing the need for effective biofilm-resistant implant materials. In this study, we present a dual-functional titanium screw (Ti-S) grafted with chitosan (Cs), a biocompatible polymer known for its osteogenic and antimicrobial properties while maintaining mechanical integrity. The chitosan-modified titanium screw (Cs-Ti-S) was prepared via chemical immobilization to enhance resistance to biofilm formation while promoting osseointegration and preserving biomechanical integrity. Biomechanical testing confirmed that chitosan modification did not compromise mechanical performance, as Cs-Ti-S exhibited a torsional yield strength of 1.70 ± 0.00 Nm compared to 1.76 ± 0.05 Nm for unmodified titanium screws (Un-Ti-S), and an axial pullout force of 68.66 ± 14.36 N for Cs-Ti-S versus 70.33 ± 9.71 N for Un-Ti-S. Micro-scratch tests revealed similar hardness values (1.26 ± 0.03 GPa for Cs-Ti-S vs. 1.40 ± 0.07 GPa for Un-Ti-S) and scratch resistance, ensuring surface durability. Gene expression analysis showed upregulated β1-integrin on Cs-Ti-S at 24 h post-infection, indicating improved osteoblast adhesion. Scanning electron microscopy (SEM) analysis confirmed significantly reduced bacterial biofilm formation on Cs-Ti-S. Moreover, the combination of povidone-iodide (PI) treatment on Cs-Ti-S surfaces significantly inhibited biofilm formation over 7 days, unlike Un-Ti-S, which retained significant adhesion. These results suggest chitosan grafting as a scalable, non-antibiotic strategy to enhance antimicrobial resistance and osseointegration.