Journal of Applied Biomaterials & Functional Materials最新文献

Cerium oxide nanoparticles (CeO₂ NPs) have unique physicochemical properties that make them suitable for various applications, particularly in biomedicine. To enhance their compatibility with biological systems, we functionalized these nanoparticles with selected amino acids, which significantly improved their potential for biomedical use, as our findings show. Cerium oxide has a fluorite-type structure and can exist in both trivalent and tetravalent states. Notably, cerium oxide also serves as an effective radioprotectant, offering selective protection to normal cells over tumor cells. The present embodiment provides functionalized cerium oxide nanoflakes with a plurality of amino acids. The surface modification by amino acids has been studied and characterized with various techniques. The cytotoxicity and the biological activity of nanoceria and the functionalization of nanoceria were evaluated. The result of this investigation shows the change in morphology structure and optical properties. The anticancer activity of the samples shows significant results against the MCF-7 and SCC-29B cell lines overall. In the case of comparing pure and functionalized nanoceria in the microbial study, the functionalization of nanoceria shows better significance by improving biological activity in some cases than synthesized/pure nanoceria and becomes suitable for biomedical applications. Therefore, the results show that the functionalization of nanoceria plays an important role in manufacturing and the possibility of using it as a therapeutic compound in the future to improve the public health of society.

With the high global prevalence of dry eye disease and around 17% attributed to aqueous deficient dry eye (ADDE), there is an urgent need for therapies targeting lacrimal gland (LG) insufficiency. Advancements in in vitro LG analysis are essential for developing effective treatments that allow for efficient, ethical, and comprehensive evaluation of both cell-based therapies and pharmaceuticals. In light of the rapid progress in 3D bioprinting for tissue engineering, this study focuses on creating a composite hydrogel derived from decellularized porcine LG, combined with alginate. This combination leverages the bioactivity of the decellularized extracellular matrix (dECM) with the favorable biomechanical properties of alginate in a single bioink. Our results demonstrate that dECM supports the in vitro culture of LG cell types effectively, while alginate provides enhanced biomechanical stability. We analyzed the biomechanical and rheological properties of the bioink and printed 3D structures containing LG-derived cells, assessing cell viability both immediately post-printing and over a 7-day culture period. The LG-based bioink showed shear-thinning behavior, reduced cell sedimentation, and resilience to shear stresses comparable to pure alginate hydrogels. Additionally, we observed excellent viability of LG epithelial and mesenchymal stromal cells. This composite bioink, combining dECM and alginate, presents improved biomechanical properties while preserving biofunctionality, representing a promising platform for in vitro LG tissue engineering.

Background: In recent years, barium titanate (BaTiO₃) has demonstrated advancements in the field of dentistry among dental ceramics. This ceramic substance has piezoelectric qualities that are comparable to those of bone, which is crucial for osseointegration. The biomedical field has made extensive use of barium titanate for its affordability, chemical stability, and non-toxicity. The use of barium titanate in dentistry is encouraged by the fact that many widely used metal alloys have unsightly hues and exhibit chemical interactions in the mouth cavity. Because BaTiO₃-based ceramics are more corrosion-resistant, have better color matching that improves esthetics, stronger, and have better radiopacity than traditional biomaterials, their use has grown.

Purpose: This review will cover the production techniques, mechanism of action, phases, and dental uses of BaTiO₃.

Conclusion: Barium titanate exhibited encouraging qualities for dental uses due to its antibacterial, biocompatible and piezoelectric action.

Background: Effective adhesion between dentin and resin materials is essential for the long-term durability of onlays, as the strength and durability of the tooth-restoration complex hinge on reliable adhesion. This study aims to enhance the adhesion of lithium disilicate onlays by employing immediate dentin sealing (IDS) and evaluates its effectiveness by comparing pull-out bond strength and microleakage with and without IDS.

Methods: Extracted human premolars were prepared and categorized into two distinct groups: Group A (with IDS) and Group B (without IDS). In Group A, the dentin surfaces were sealed immediately after tooth preparation using an adhesive resin. In Group B, no sealing was performed before bonding the lithium disilicate restorations. Pull-out bond strength was assessed utilizing universal testing machine. Microleakage was evaluated through dye penetration analysis after thermocycling and sectioning of the samples. For statistical interpretation, one-way ANOVA followed by Tukey's post-hoc test was applied.

Results: The pull-out bond strength was significantly higher in Group A compared to Group B (p = 0.0001). Microleakage evaluation revealed less dye penetration in Group A, indicating superior marginal integrity with IDS. The high-resolution images provided clearer visualization of the interfaces and the extent of dye penetration.

Conclusion: Immediate dentin sealing significantly enhances the pull-out bond strength of lithium disilicate onlay and reduces microleakage. These findings suggest that IDS is a beneficial step in the bonding protocol for lithium disilicate restorations, potentially improving the longevity and performance of the restorations.

Introduction: Intensive research is dedicated to the development of novel biomaterials and medical devices to be used as grafts in reconstructive surgery, with the purpose of enhancing their therapeutic effectiveness, safety, and durability. A variety of biomaterials, from autologous bone to polymethylmetacrylate, polyether ether ketone, titanium, and calcium-based ceramics are used in cranioplasty. Porous hydroxyapatite (PHA) is reported as a possible material for bone reconstruction, with good signs of biocompatibility, osteoconductive and osteointegrative properties. In the present paper we studied the possible antibacterial properties of PHA in a laboratory test in order to provide a possible overview of the occurrence of post-operative infections in PHA cranioplasty.

Method: The test method has been designed to evaluate the potential antimicrobial activity of specimens under dynamic contact conditions to overcome difficulties in ensuring contact of inoculum to the specimen surface. The test was conducted using Staphylococcus aureus ATCC6538 as a bacterial strain.

Results: Two experimental sets were performed to evaluate the antimicrobial properties of the specimens against two different Staphylococcus aureus concentrations. The first preliminary test (a) verified the antibacterial property at 0, 1, 2, and 4 h of contact time; the second confirmatory test (b) was repeated to verify the antibacterial property at 0, 4, 8 h. In the first experiment, after the first hour of contact, the bacterial inoculum was reduced by 7.96% compared to "inoculum only," which increased to 26.11% at the second hour, and up to 52.33% after 4 h. In the second experiment, the confirmation test showed that bacterial growth reaches maximum inhibition after 4 h of contact. At 4 h, there was a higher bacterial reduction of 72.93%, which decreased at 8 h (36.45%).

Conclusion: Analyzing the growth trend of viable microorganisms under Dynamic Contact Conditions it can be seen that PHA cranioplasty appears to inhibit exponential growth by inducing bacterial stasis in the early hours of contact, reaching a maximum reduction within 4 h, in this adopted experimental condition.

The use of adjunct chemical substances in the early postoperative period of periodontal surgical procedures is recommended due to the potential risk of trauma in the operated area. Chlorhexidine digluconate mouthwash is widely used but can cause adverse effects. Phthalocyanine derivatives are being studied as an alternative, demonstrating good antimicrobial activity, especially in the self-activated form, which does not require additional light or chemicals. The objective of this study is to compare the cytotoxicity of different concentrations of a phthalocyanine (PHY) with chlorhexidine (CHX) and assess their influence on fibroblast cell migration. Different concentrations of CHX and PHY (0.0075%-0.12%) were evaluated using NIH 3T3 fibroblasts. Cell viability was assessed by the MTT and crystal violet (CV) assay; CHX and PHY (0.0075% and 0.12%) were also evaluated by in vitro wound healing assay. PHY was less cytotoxic compared to CHX, based on cell viability assays. PHY did not interfere with experimental healing, allowing cell migration similar to the positive control with both concentrations (PHY 0.0075% and 0.12%) and only 0.0075% CHX allowed cell migration. In a comparative analysis, PHY showed less cytotoxicity than CHX and PHY concentrations of 0.0075% and 0.015% was non-toxic even after 48 h of contact with the cells. This in vitro evaluation demonstrated that PHY was less cytotoxic to NIH 3T3 fibroblasts compared to CHX. Furthermore, the different concentrations of PHY did not interfere negatively in the healing of experimental wounds.

Commercially available Dacron (woven polyester) grafts are used for routine open surgical repair of thoracic aortic aneurysms. Despite durable and biocompatible, these grafts do not reproduce the natural mechanical properties of the aorta. Therefore, the aim of this project was to develop an innovative graft that additionally exhibits physiological aortic compliance. To achieve this result, multi-layered tubular aortic grafts were created by electrospinning of a thermoplastic polyurethane. To reduce permeability, a gelatin-coating was added. Three groups (G_1-3; n = 5) with varying layer designs were evaluated regarding the main mechanical properties of vascular grafts such as suture retention strength, permeability and static and dynamic compliance. G₃, which combined electrospinning with a stable silicone-coated inlay was chosen for the fabrication of medical grade thermoplastic polyurethane grafts (G_m; n = 6). Dynamic compliance values of 19.68 ± 11.5%/100 mmHg (50-90 mmHg), 15.18 ± 8.7%/100 mmHg (80-120 mmHg) and 14.56 ± 7.4%/100 mmHg (110-150 mmHg) were achieved. The compliance was higher than for Dacron and ePTFE grafts and comparable to the normal sized ascending aorta of around 16%/100 mmHg in a healthy human and porcine aortic compliance of 14.3%/100 mmHg. Static compliance was successfully tested up to 350 mmHg. No significant changes in graft diameter or delaminations of the graft layers were detected after compliance testing. Therefore, by combining electrospinning with a durable inlay, both elasticity and recoverability are obtained, resulting in a promising alternative to the gold-standard in open-surgical treatment of thoracic aortic pathologies.

Peripheral nerve tissue engineering is a field that uses cells, growth factors and biological scaffold material to provide a nutritional and physical support in the repair of nerve injuries. The specific properties of injectable human amniotic membrane-derived hydrogel including growth factors as well as anti-inflammatory and neuroprotective agents make it an ideal tool for nerve tissue repair, and metformin may also aid in nerve regeneration. The aim of this study was to investigate the effects of hydrogel derived from amniotic membrane (AM) along with metformin (MET) administration in the repair of sciatic nerve injury in male rats. We randomly divided 60 male rats into five groups. A control and four sciatic nerve compression groups including model; hydrogel; metformin and mix which received hydrogel and metformin. The recovery rate was assessed by Sciatic Functional Index (SFI), Static Sciatic Index (SSI) and von-frey test. Conduction velocity of the sciatic nerve was measured by Electrophysiological studies, and histological evaluations were performed 14 days after injury. SFI, SSI, latency time, remyelination rate and the expression of NF-200 and S-100β improved in hydrogel group. Response to mechanical stimulus, myelin density, axonal regeneration, and myelin sheath reconstruction improved in the mix group. The gastrocnemius muscle index was significantly reduced in the experimental groups while collagen fibers increased in these groups. These findings suggest that injection of hydrogel derived from decellularized amniotic membrane into the epineurium can be promoted reconstruction of peripheral nerve injury and improved functional nerve recovery. Also, metformin administration can reinforce the therapeutic effect of the hydrogel.

Eucalyptus species are known for their decongestant and antimicrobial properties, mainly due to their essential oil. However, significant challenges persist in maintaining the stability and durability of the essential oils' effectiveness. This study examines the use of polymeric hollow fibers for encapsulating Eucalyptus essential oil (EE) to improve its stability and effectiveness in treating nasal congestion. The EE was obtained by hydro-distillation method, and analyzed using gas chromatography-mass spectrometry (GC-MS). A dialysis cartridge containing polysulfone hollow fibers was used to load the EE, and their permeability, morphology, and stability were assessed. Fourier-transform infrared spectroscopy (FT-IR) and headspace sampling with gas chromatography-flame ionization detection (GC-FID) were employed to monitor EE release and the stability of EE-loaded hollow fibers. GC/MS analysis identified 20 major components with 1,8-cineole being the predominant compound at 59.32%. Physicochemical characterization of hollow fibers revealed complete permeability to EE. FT-IR spectra suggested potential interactions between EE and the fibers. Release studies indicated that over 80% of EE was released from the fibers within 180 min. Headspace analysis confirmed the presence and stability of 1,8-cineole in the loaded fibers. The stability test demonstrated no significant changes in the EE-loaded fibers over 6 days. This study indicated that the capillary properties of the EE-loaded hollow fibers facilitate oil loading, and headspace sampling provides a more efficient analysis. The successful and stable release of EE from the fibers, highlights the potential of hollow fibers for controlled drug delivery. However, conducting more accurate experiments can help deduce more logical results.

The aim of the study is to evaluate the effect of fluoride varnishes on both the color stability and surface microhardness of different fluoride-releasing restorative materials exposed to beverages commonly consumed by children . This study was conducted as an in vitro experimental study design. Three different restorative materials (Dyract XP, Beautifil II, and Cention N) and a colorless fluoride varnish were used. The solutions in which the samples were immersed were selected as beverages commonly preferred by children: cherry juice, chocolate milk, and cola. Color changes of the samples were measured using a spectrophotometer at 1, 7, 14, and 28 days and calculated according to the CIEDE2000 total color difference formula. Surface microhardness values were measured using a digital microhardness testing device at 1 and 28 days. To assess the effects of variables and their interactions in repeated observation designs, generalized linear models and generalized linear mixed models were fitted. Following model estimation, Tukey's-adjusted estimated marginal means were computed to identify significant pairwise differences. Fluoride-releasing restorative materials exhibited varying degrees of color change and decrease in surface microhardness when immersed in different staining solutions. Among the tested materials, Cention N demonstrated the greatest color stability (ΔE=1.01 for fluoride applied group, ΔE=1.45 for the group without fluoride application) and least reduction in surface microhardness. Fluoride application initially caused a slight discoloration immediately after application. However, following immersion in different solutions, fluoride application appeared to enhance color stability (ΔE=1.59 in the varnish-applied group, ΔE=2.21 in the group without varnish application), but did not have a statistically significant effect on the surface microhardness. A negative correlation was observed between color change and surface microhardness; as the surface microhardness decreased, the extent of color change increased. This study highlights the prominent role of intraoral environmental factors in influencing the durability and aesthetic properties of fluoride-releasing restorative materials. Topical fluoride application has a beneficial effect on the color stability with a more pronounced effect observed with Cention N.