Journal of biomedical materials research. Part B, Applied biomaterials最新文献

Suture selection influences wound healing, patient comfort, and infection risk in implant surgery. Although monofilament sutures are commonly recommended for implant surgery, the comparative clinical performance of different types of monofilament sutures remains underexplored. This study compared the clinical and microbiological performance of polyamide and polytetrafluoroethylene (PTFE) sutures. A split-mouth design was used in 19 patients (38 implant sites) to compare wound healing, patient comfort, and bacterial adherence associated with polyamide and PTFE sutures. Wound healing was assessed using the early wound healing score (EHS, 0–10 scale), patient comfort via a visual analog scale (VAS, 1–10), and bacterial colonization using real-time quantitative PCR (qPCR) analysis of seven oral pathogens. Knot retention was recorded on days 0 and 7. Mean early wound healing scores were similar between PTFE (6.47 ± 0.52) and polyamide (6.63 ± 0.63) (p > 0.05). No significant differences were found between the two groups regarding surrounding tissue irritation (p > 0.05). However, knot stability decreased significantly for both materials, with polyamide showing higher knot loss (44.4% vs. 22.2%, p = 0.008). A significant number of Porphyromonas gingivalis were detected in PTFE compared to polyamide, which demonstrated enhanced reepithelialization and minimal tissue reaction. Both suture types achieved satisfactory healing and patient comfort, but their distinct microbial adhesion patterns may influence long-term peri-implant outcomes. Polyamide demonstrated lower P. gingivalis colonization and better re-epithelialization, suggesting potential clinical advantages.

Microgels are increasingly recognized as versatile building blocks for granular cell scaffolds, offering advantages over bulk hydrogels for a variety of biomedical applications. While existing methods for scaffold fabrication often require multistep processes involving separate microgel formation and assembly, here we introduce a streamlined, one-pot approach that achieves microgel formation and scaffold assembly in minutes. This developed method is robust, reproducible, user-friendly, and requires no specialized equipment, making it broadly accessible. Specifically, aqueous two-phase separation (ATPS) was utilized to form ~2 μm gelatin methacrylate (GelMA) microgels in sodium sulfate salt solution, which rapidly “clicked” to form macroporous scaffolds under UV light. Various parameters were modulated to observe the effect on scaffold formation including timing of UV exposure, salt concentration, photoinitiator concentration, and polymer concentration. Our results indicated a mechanically stable scaffold able to quickly imbibe water due to its interconnected macropores. U-87 glioblastoma, NIH 3T3 fibroblast, and ATDC5 chondrocyte cells were successfully encapsulated within these granular scaffolds and exhibited an elongated morphology at 24 h and > 90% viability over 14–21 days of culture. The ability to produce microgel scaffolds containing living cells in one step opens new routes to the production of cell-laden porous scaffolds.

This study aimed to biologically modify polyetheretherketone (PEEK) using cell sheets after chemical modification, with the goal of enhancing its bioactivity and improving its integration with dental tissue. To achieve this, sulfonated PEEK (SPEEK) and/or boron-doped nanohydroxyapatite (B-nHAp)-coated SPEEK (SPEEK-B-nHAp) materials were combined with periodontal ligament (PDL) or PDL-co-human umbilical vein endothelial (HUVEC) cell sheets. PDL and PDL-co-HUVEC cell sheets were obtained from 12-well plates over a 4-day period using L-ascorbic acid induction (100 μg/mL) and a concentrated cell density of 1.0 × 10⁵ cells/cm². Both PDL and co-culture cell sheets adhered well to and proliferated on the surfaces of SPEEK and SPEEK-B-nHAp. However, the co-culture cell sheet groups showed faster growth compared to the PDL cell sheet groups on both SPEEK and SPEEK-B-nHAp materials at each time point. Western blot and RT-PCR analyses revealed a significant increase in early- and mid-term osteogenic markers in PDL cell sheets on both SPEEK and SPEEK-B-nHAp surfaces. Additionally, late-stage osteogenic and angiogenic markers were enhanced in the co-culture cell sheets on both SPEEK and SPEEK-B-nHAp samples. This study concluded that PDL-co-HUVEC cell sheets covering SPEEK-B-nHAp surfaces can effectively support bone-implant integration and represent a promising modification approach for PEEK dental implants.

Urethral stricture is the narrowing of the urethra caused by the growth of aberrant tissue after an injury. Actual post-operative treatment requires the placement of a Foley catheter for external urinary drainage after surgery. However, it requires a second intervention for removal, and the contact with the external environment and non-biodegradable composition even aggravates urinary tract infections (UTIs) in 7.12% of patients. Thus, we developed a completely biodegradable intraurethral device (BID) as an alternative to catheterization. BID is a continuous-walled hollow tubular stent with outer wall corrugations composed of poly(d,l-lactide-co-ε-caprolactone) copolymer synthesized by ring-opening polymerization, using a bismuth-based catalyst. Complying with EU Medical Device Regulation 2017/745, BID was manufactured by injection molding following ISO 13485 and irradiated by e-beam, according to ISO 11137 and 11737. Physico-chemical characterization was evaluated following ISO 10993, showing a scalable synthetic procedure with reproducible composition, high molecular weight, adequate thermal properties, and metal content below its cytotoxic level. Scanning electron microscopic analysis confirmed consistent dimensions and no detrimental effect in the device after irradiation. Additionally, hydrolytic degradation studies (static and dynamic) showed complete degradation of BID after 90 days, obtained by the tailored composition of the synthesized copolymer and aligned with the tissue regeneration process. Mechanical properties confirmed a consistent tubular shape up to 28 days and no migration of the device even at a maximum urine flow of 1500 mL/min thanks to the tailored corrugated design of BID. These findings position BID as a promising alternative in post-operative urethral stricture management, addressing critical limitations of current practices. Hopefully, our BID might provide a biodegradable solution, minimizing UTIs and migration, and eliminating the current second intervention for catheter removal.

Periprosthetic joint infection (PJI) is a devastating complication of total joint arthroplasty, often necessitating two-stage revision surgery with antibiotic-loaded bone cement (ALBC) spacers, which cannot maintain therapeutic local antibiotic concentrations over time. This study evaluated the long-term stability, antimicrobial efficacy, and biocompatibility of an alternative material, submicron gentamicin sulfate-loaded ultrahigh molecular weight polyethylene (SM-GS/UHMWPE), in vitro and in vivo by using a subcutaneous rat model. SM-GS/UHMWPE implants containing 6 wt% and 10 wt% gentamicin sulfate (GS) were fabricated and tested in vitro and simultaneously in vivo by subcutaneous implantation in rats for 4, 8, and 26 weeks. Gentamicin stability was assessed using nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography-mass spectrometry (LC–MS/MS). Antimicrobial efficacy against Staphylococcus aureus was determined via bacterial culture assays. Mechanical integrity was evaluated using tensile testing in vitro. Systemic toxicity was assessed through liver and kidney function markers, and histological analysis of kidney and skin tissues was performed. NMR and LC–MS/MS confirmed that gentamicin remained chemically stable over 26 weeks in vivo and in vitro. Antimicrobial testing showed sustained bacterial inhibition, with implants containing 10% GS achieving a 3.5-log reduction in bacterial counts for 6 months. Mechanical testing demonstrated minimal changes in tensile properties over time. Serum biochemical markers remained within normal ranges, and histological evaluation showed no significant inflammation or tissue damage. Gentamicin elution profiles indicated sustained release, maintaining intraarticular levels above 100 times the minimum inhibitory concentration (MIC) of S. aureus for 6 months. SM-GS/UHMWPE implants demonstrated prolonged antibiotic release while maintaining mechanical integrity, antimicrobial efficacy, and biocompatibility. These findings support the potential use of SM-GS/UHMWPE as a next-generation antibiotic-eluting spacer for PJI treatment, offering an alternative to ALBC for sustained drug release and reduced systemic toxicity risks.

Poly(ε-caprolactone) (PCL) is a biodegradable polyester known for its low melting point and high flexibility, making it ideal for various medical device applications. In this study, we introduce a conductive nanocarbon black-blended PCL as a reinforced ink for fabricating flexible and degradable piezoresistive bioelectrodes. This approach enables the creation of a piezoresistive bioelectrode optimized for precise biomechanical sensing. The bioelectrode exhibits exceptional mechanoelectrical stability under high tension (> 350%), repeated drawing (> 40%, 100 cycles), long-term bending (> 7000 cycles), extrusion (> 10,000 cycles), and torsion (> 90°). When assembled into flexible piezoresistive sensors, the sensor achieves a high sensitivity (2.66 kPa⁻¹ in the range of 0–3 kPa), along with excellent repeatability and durability (10,000 cycles at 5 N). The sensor has promising applications in human health monitoring, including finger, wrist, and elbow activity tracking, as well as knee joint space sensing for guiding precise surgical operations.

Chronic wounds, often complicated by microbial growth and insufficient regeneration, pose a significant challenge. To address these issues, we developed a hydrogel dressing made from natural polymers, tragacanth gum (TG) and chitosan (CS), incorporated synthesized copper oxide nanoparticles (CuO NPs) to promote wound healing and inhibit microorganisms at the wound site. We synthesized CuO NPs using a reduction method with pomegranate peel extract and analyzed their characteristics. The TG/CS hydrogel was then prepared and loaded with the synthesized NPs, followed by relevant physicochemical analysis. The hydrogel's degradation rate and antibacterial activity were determined, and its effects on cell migration and viability in skin fibroblasts were evaluated using suitable methods. The synthesized CuO NPs showed nanometer dimensions (about 30–50 nm) with a consistent spherical morphology, and compositional analysis confirmed the presence of their constituent elements. The TG/CS hydrogel incorporating CuO NPs displayed a smooth and uniform appearance with a porous structure featuring interconnected micrometer-sized pores. Infrared spectroscopy confirmed the functional groups of the hydrogel components and the presence of the NPs. Moreover, this hydrogel demonstrated high liquid absorption, porosity, and stable degradation over several days. It significantly inhibited the growth of both Gram-positive and Gram-negative bacteria. The hydrogel containing 10 wt% CuO NPs stimulated fibroblast cell growth and, most importantly, accelerated wound healing by inducing cell migration and filling the scratch gap within 48 h. Overall, the natural TG/CS hydrogel containing CuO NPs has a high potential to expedite wound healing as a multifunctional wound dressing.