International Journal of Biomaterials最新文献

The high degree of chemical modification of the chitosan chains due to protonated amine groups allows them to react with many negatively charged surfaces as anionic polymers and cell membranes, resulting in an attractive material for medical and pharmaceutics applications. Incorporating ionic iodine (I^- and IO₃ ^-) on chitosan chains is a direct way to successfully obtain chitosan-iodine nanoparticles (CSNPs-I and CSNPs-IO₃) through ionic gelation. The nanoparticles (NPs) present a hemispherical morphology with sizes around 30-70 nm for CSNPs-I and CSNPs-IO₃, similar to chitosan NPs, in accordance with SEM and DLS techniques. The XRD characterization did not show noticeable differences in the crystallinity index (CI) for CSNPs and CSNPs-I, 48.4 and 49.3%, respectively, but for CSNPs-IO₃, the CI decreased to 43.85%. The cytotoxic effects on human tumor cells of chitosan and iodine-modified chitosan nanoparticles (CSNPs-I and CSNPs-IO₃) were evaluated for 24 h in a range from 0.15 mg/mL to 0.95 mg/mL concentrations, where CSNPs-IO₃ presented the lower viability for lung cancer A549, followed by cervical cancer HeLa cell and finally breast cancer MDA-MB-231, with a weight content of iodate ion in a range of 8.7 to 15 μg. This work presents the possibility of exploring chitosan-iodine NPs in medical applications.

Bone tissue engineering necessitates the development of scaffolds with optimal properties to provide a suitable microenvironment for cell adhesion, proliferation, and osteogenic differentiation. The selection of appropriate scaffold materials remains a critical challenge in this field. In this study, we aimed to address this challenge by evaluating and comparing the performance of hydrogel scaffolds reinforced with β-tricalcium phosphate (β-TCP), allograft, and a combination of allograft and strontium hydroxyapatite (SrHA). In this study, scaffolds containing the following compounds with a weight ratio of 75 : 25 : 50 were made using a 3D printer: group (1) alginate + gelatin + β-TCP (TCP), group (2) alginate + gelatin + allograft (Allo), and group (3) alginate + gelatin + allograft + strontium hydroxyapatite (Str). Stem cells extracted from rat bone marrow (rBMSCs) were cultured on scaffolds, and cell proliferation and differentiation tests were performed. Also, the physical and chemical properties of the scaffolds were investigated. The two/one-way analysis of variance (ANOVA) by Tukey's post hoc test was performed. There was no significant difference between scaffolds with pore size and porosity. TCP scaffolds' mechanical strength and degradation rate were significantly lower than the other two groups (P < 0.05). Also, the swelling ratio of Allo scaffolds was higher than in other samples. The amount of cell proliferation in the samples of the TCP group was lower than the other two, and the Allo samples had the best results in this concern (P < 0.01). However, the scaffolds containing strontium hydroxyapatite had significantly higher bone differentiation compared to the other two groups, and the lowest results were related to the scaffolds containing β-TCP. Hydrogel scaffolds reinforced with allograft or its combination with strontium showed better physicochemical and biological behavior compared to those reinforced with β-TCP. Besides, adding strontium had a limited impact on the physicochemical features of allograft-containing scaffolds while improving their potential to induce osteogenic differentiation.

Objectives: This study aimed to assess the effect of addition of bioactive glass (BG) on the setting time and antibacterial activity of mineral trioxide aggregate (MTA) against Enterococcus faecalis (E. faecalis).

Materials and methods: In this in vitro study, BG was synthesized by the sol-gel technique and added to MTA powder in certain ratios. Three groups of specimens were fabricated from pure MTA, MTA mixed with 10wt% BG, and MTA mixed with 20wt% BG. The setting time of specimens was measured according to ISO9917-2007. Direct contact test was used to assess the antimicrobial activity of the three groups against E. faecalis. Data were analyzed by repeated measures ANOVA (alpha = 0.05).

Results: Addition of BG (in both concentrations) to MTA decreased its setting time and improved its antibacterial activity against E. faecalis (p < 0.05). By an increase in concentration of BG (20%), the antimicrobial activity further improved (p < 0.05).

Conclusion: Addition of BG to MTA in 10wt% and 20wt% concentrations decreased its setting time and improved its antibacterial activity against E. faecalis.

It is well known that soft tissue quality and quantity around dental implants is of paramount importance for later peri-implant health. For this purpose, the clinical and histological outcomes of the peri-implant mucosa, following soft tissue augmentation for soft tissue improvement with a novel prehydrated porcine acellular dermal matrix graft (PPADMG) in conjunction with simultaneous implant placement, were evaluated in this case series. Twenty-two patients were included in the study. They underwent a late implant placement protocol combined with PPADMG for soft tissue augmentation. A punch biopsy was taken at the time of uncovery of the submerged healed implant after a mean of 157 days healing time. Supracrestal soft tissue height (STH) was measured at the time of implant placement and uncovery. All sites showed a clinical increase in STH. The histological structure of the biopsies resembled a similar structure as found in the healthy oral mucosa. No unexpected tissue reactions could be found. Within the limits of this clinical and histological study, it may be concluded that STH improvement with this novel porcine-derived acellular dermal matrix, in combination with simultaneous implant placement, is a viable option to create a peri-implant tissue thickness and stability.

This study aimed to evaluate the mechanical behaviors of thermoformed and 3D-printed retainers with different thicknesses. Thermoformed retainers (Duran) and 3D-printed retainers (Dental LT Clear V2 and NextDent Ortho Flex) were fabricated at thicknesses of 0.5, 0.75, and 1 mm. Five samples of each material were subjected to compression, tensile, and flexural testing with the universal testing machine (Instron Ltd., Buckinghamshire, England). The results revealed that the mechanical behaviors were significantly influenced by thickness in each type of material. The increased thickness tended to increase strength and modulus in all three tests. However, Dental LT Clear V2 and Duran showed that flexural strength and modulus were inversely related to thickness. The compressive test revealed significantly greater compressive resistance in 3D-printed groups, except for the NextDent Ortho Flex at 0.5 mm. The tensile test showed that Dental LT Clear V2 at all thicknesses demonstrated significantly higher tensile strength and modulus, while NextDent Ortho Flex was significantly lowest at any thickness in tensile and flexural properties. In conclusion, the thickness significantly influenced the mechanical behaviors of the 3D-printed retainers. The 0.75 mm thickness of Dental LT Clear V2 could be considered as an alternative to fabricated retainers due to its similar mechanical properties compared with the thermoformed material.

Three-dimensional (3D) printing is becoming more prevalent in the dental sector due to its potential to save time for dental practitioners, streamline fabrication processes, enhance precision and consistency in fabricating prosthetic models, and offer cost-effective solutions. However, the effect of aging in artificial saliva of this type of material has not been explored. To assess the physical and mechanical properties of the two types of 3D-printed materials before and after being subjected to artificial saliva, a total of 219 acrylic resin specimens were produced. These specimens were made with two types of 3D-printed materials, namely, NextDent (ND) and Formlabs (FLs), and a Schottlander heat-cured (HC) resin material that was used as a control. Water sorption and solubility specimens (n = 5) were tested after three months of storage in artificial saliva. Moreover, the Vickers hardness, Martens hardness, flexural strength/modulus, and impact strength were evaluated both under dry conditions and after three months of storage in artificial saliva. The degree of conversion (DC), elemental analysis, and filler content were also investigated. The ANOVA showed that 3D-printed resins had significantly greater sorption than the control group (p < 0.05). However, the flexural strength values of the 3D-printed materials were significantly greater (p < 0.05) than those of the heat-cured material. The DC of the 3D-printed resins was lower than that of the control group, but the difference was not significant (p > 0.05). The 3D-printed materials contained significantly more filler than the control (p < 0.05). Moreover, the artificial saliva had a significant effect on the Vickers hardness for all tested groups and on the Martens hardness for the control group only (p < 0.05). Compared with conventional heat-cured materials, 3D-printed denture base materials demonstrated relatively poorer performance in terms of sorption, solubility, and DC but exhibited either comparable or superior mechanical properties. The aging process also influenced the Vickers and Martens' hardness. The strength of the 3D-printed materials was in compliance with ISO recommendations, and the materials could be used alongside conventional heat-cured materials.

Introduction: Periodontitis therapy employing nanomaterials with submicron sizes holds promise for enhancing osteogenesis and facilitating periodontal cell proliferation. This study aims to assess the potential of nanoparticle-based rice husk liquid smoke (n-RHLS) in an animal model of periodontitis by evaluating the expression of osteoprotegerin (OPG), receptor activator of nuclear factor-kβ (RANK), and receptor activator of nuclear factor-kβ ligand (RANKL).

Methods: Twenty-eight male Wistar rats were inoculated with 10⁹ CFU/ml of Porphyromonas gingivalis in the sulcus mandibular incisor region to create periodontitis and subsequently treated with n-RHLS while the control with saline. Immunohistochemical staining was performed on the mandibular incisor to assess OPG, RANK, and RANKL expression 2 and 7 days after treatment.

Results: OPG expression exhibited a significant increase at both 2 and 7 days, while RANKL expression decreased notably after 7 days of treatment using n-RHLS (p < 0.05). In contrast, RANK expression did not show significant differences compared to the control groups (p > 0.05).

Conclusion: Nanostructured liquid smoke derived from rice husk nanoparticles (n-RHLS) demonstrates potential as a therapeutic agent for periodontitis, especially on OPG/RANK/RANKL expression, by modulating OPG and RANKL expression to support periodontal tissue health.

Cancer and bacterial infections are major global health concerns driving the need for innovative medicines. This study investigated alginate nanoparticles loaded with essential oils (EOs) from Cuminum cyminum and Zataria multiflora as potential drug delivery systems. The nanoparticles were comprehensively characterized using techniques such as gas chromatography-mass spectrometry (GC-MS), dynamic light scattering (DLS), zetasizer, attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and ultraviolet-visible spectroscopy (UV-Vis). Their biological properties against two human skin cancer cell lines (A-375 and A-431) and three bacteria (Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus) were also evaluated. Alginate nanoparticles containing C. cyminum and Z. multiflora EOs exhibited sizes of 160 ± 8 nm and 151 ± 10 nm, respectively. Their zeta potentials and encapsulation efficiencies were -18 ± 1 mV and 79 ± 4%, as well as -27 ± 2 mV and 86 ± 5%, respectively. The IC₅₀ values against the tested cell lines and bacteria revealed superior efficacy for nanoparticles containing Z. multiflora EO. Considering the proper efficacy of the proposed nanoparticles, the straightforward preparation method and low cost suggest their potential for further in vivo studies.

Polyurethanes (PUs) are versatile polymers used in medical applications due to their high flexibility and fatigue resistance. PUs are widely used for synthetic blood vessels, wound dressings, cannulas, and urinary and cardiovascular catheters. Many scientific reports indicate that surface wettability is crucial for biocompatibility and bacterial adhesion. The use of oxygen plasma to modify PUs is advantageous because of its effectiveness in introducing oxygen-containing functional groups, thereby altering surface wettability. The purpose of this study was to investigate the effect of the modification of the oxygen plasma of polyurethane on its biocompatibility with lung tissue (A549 cell line) and the adhesion of Gram-positive bacteria (S. aureus and S. epidermidis). The results showed that the modification of polyurethane by oxygen plasma allowed the introduction of functional groups containing oxygen (-OH and -COOH), which significantly increased its hydrophilicity (change from 105° ± 2° to 9° ± 2°) of PUs. Surface analysis by atomic force microscopy (AFM) showed changes in PU topography (change in maximum height from ∼110.3 nm to ∼32.1 nm). Moreover, biocompatibility studies on A549 cells showed that on the PU-modified surface, the cells exhibited altered morphology (increases in cell surface area and length, and thus reduced circularity) without concomitant effects on cell viability. However, serial dilution and plate count and microscopic methods confirmed that plasma modification significantly increased the adhesion of S. aureus and S. epidermidis bacteria. This study indicate the important role of surface hydrophilicity in biocompatibility and bacterial adhesion, which is important in the design of new medical biomaterials.

The process of decellularization is crucial for producing a substitute for the absent tracheal segment, and the choice of agents and methods significantly influences the outcomes. This paper aims to systematically review the efficacy of diverse tracheal decellularization agents and methods using the PRISMA flowchart. Inclusion criteria encompassed experimental studies published between 2018 and 2023, written in English, and detailing outcomes related to histopathological anatomy, DNA quantification, ECM evaluation, and biomechanical characteristics. Exclusion criteria involved studies related to 3D printing, biomaterials, and partial decellularization. A comprehensive search on PubMed, NCBI, and ScienceDirect yielded 17 relevant literatures. The integration of various agents and methods has proven effective in the process of tracheal decellularization, highlighting the distinct advantages and drawbacks associated with each agent and method.