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BACKGROUND: The process of bone healing is complex and involves the participation of osteogenic stem cells, extracellular matrix, and angiogenesis. The advancement of bone regeneration materials provides a promising opportunity to tackle bone defects. This study introduces a composite hydrogel that can be injected and cured using UV light. RESULTS: Hydrogels comprise bioactive glass (BG) and PCL@GelMA coaxial nanofibers. The addition of BG and PCL@GelMA coaxial nanofibers improves the hydrogels mechanical capabilities (353.22 ± 36.13 kPa) and stability while decreasing its swelling (258.78 ± 17.56%) and hydration (72.07 ± 1.44%) characteristics. This hydrogel composite demonstrates exceptional biocompatibility and angiogenesis, enhances osteogenic development in bone marrow mesenchymal stem cells (BMSCs), and dramatically increases the expression of critical osteogenic markers such as ALP, RUNX2, and OPN. The composite hydrogel significantly improves bone regeneration (25.08 ± 1.08%) in non-healing calvaria defects and promotes the increased expression of both osteogenic marker (OPN) and angiogenic marker (CD31) in vivo. The expression of OPN and CD31 in the composite hydrogel was up to 5 and 1.87 times higher than that of the control group at 12 weeks. CONCLUSION: We successfully prepared a novel injectable composite hydrogel, and the design of the composite hydrogels shows significant potential for enhancing biocompatibility, angiogenesis, and improving osteogenic and angiogenic marker expression, and has a beneficial effect on producing an optimal microenvironment that promotes bone repair.

Durable and conductive interfaces that enable chronic and high-resolution recording of neural activity are essential for understanding and treating neurodegenerative disorders. These chronic implants require long-term stability and small contact areas. Consequently, they are often coated with a blend of conductive polymers and are crosslinked to enhance durability despite the potentially deleterious effect of crosslinking on the mechanical and electrical properties. Here the grafting of the poly(3,4 ethylenedioxythiophene) scaffold, poly(styrenesulfonate)-b-poly(poly(ethylene glycol) methyl ether methacrylate block copolymer brush to gold, in a controlled and tunable manner, by surface-initiated atom-transfer radical polymerization (SI-ATRP) is described. This "block-brush" provides high volumetric capacitance (120 F cm─3), strong adhesion to the metal (4 h ultrasonication), improved surface hydrophilicity, and stability against 10 000 charge-discharge voltage sweeps on a multiarray neural electrode. In addition, the block-brush film showed 33% improved stability against current pulsing. This approach can open numerous avenues for exploring specialized polymer brushes for bioelectronics research and application.

The mechanical interactions among integrated cellular structures in soft tissues dictate the mechanical behaviors and morphogenetic deformations observed in living organisms. However, replicating these multifaceted attributes in synthetic soft materials remains a challenge. In this work, we develop a smart hydrogel system featuring engineered stiff cellular patterns that induce strain-driven heterogeneous subdomains within the hydrogel film. These subdomains arise from the distinct mechanical responses of the pattern and film domains under applied mechanical forces. Unlike previous studies that incorporate reinforced inclusions into soft matrices to tailor material properties, our method manipulates the localization, integration, and interaction of these subdomain building blocks within the soft film. This enables extensive tuning of both local and global behaviors. Notably, we introduce a subdomain-interface mechanism that allows for the concurrent customization and decoupling of mechanical properties and shape transformations within a single material system-an achievement rarely accomplished with current synthetic soft materials. Additionally, our use of in-situ imaging characterizations, including full-field strain mapping via digital imaging correlation and reciprocal-space patterns through fast Fourier transform analysis of real-space pattern domains, provides rapid real-time monitoring tools to uncover the underlying principles governing tailored multiscale heterogeneities and intricate behaviors.

Timely and effective interventions after tracheal mucosal injury are lack in clinical practices, which elevate the risks of airway infection, tracheal cartilage deterioration, and even asphyxiated death. Herein, we proposed a biomaterial-based strategy for the repair of injured tracheal mucosal based on a copper hydrogen phosphate nanosheets (CuHP NSs) functionalized commercial hydrogel (polyethylene glycol disuccinimidyl succinate-human serum albumin, PH). Such CuHP/PH hydrogel achieved favorable injectability, stable gelation, and excellent adhesiveness within the tracheal lumen. Moreover, CuHP NSs within the CuHP/PH hydrogel effectively stimulate the proliferation and migration of endothelial/epithelial cells, enhancing angiogenesis and demonstrating excellent tissue regenerative potential. Additionally, it exhibited significant inhibitory effects on both bacteria and bacterial biofilms. More importantly, when injected injured site of tracheal mucosa under fiberoptic bronchoscopy guidance, our results demonstrated CuHP/PH hydrogel adhered tightly to the tracheal mucosa. The therapeutic effects of the CuHP/PH hydrogel were further confirmed, which significantly improved survival rates, vascular and mucosal regeneration, reduced occurrences of intraluminal infections, tracheal stenosis, and cartilage damage complications. This research presents an initial proposition outlining a strategy employing biomaterials to mitigate tracheal mucosal injury, offering novel perspectives on the treatment of mucosal injuries and other tracheal diseases.

Spinal cord injury (SCI) is a life-altering event, which often results in loss of sensory and motor function below the level of trauma. Biomaterial therapies have been widely investigated in SCI to promote directional regeneration but are often limited by their pre-constructed size and shape. Herein, the design parameters of microporous annealed particles (MAPs) are investigated with tubular geometries that conform to the injury and direct axons across the defect to support functional recovery. MAP tubes prepared from 20-, 40-, and 60-micron polyethylene glycol (PEG) beads are generated and implanted in a T9-10 murine hemisection model of SCI. Tubes attenuate glial and fibrotic scarring, increase innate immune cell density, and reduce inflammatory phenotypes in a bead size-dependent manner. Tubes composed of 60-micron beads increase the cell density of the chronic macrophage response, while neutrophil infiltration and phenotypes do not deviate from those seen in controls. At 8 weeks postinjury, implantation of tubes composed of 60-micron beads results in enhanced locomotor function, robust axonal ingrowth, and remyelination through both lumens and the inter-tube space. Collectively, these studies demonstrate the importance of bead size in MAP construction and highlight PEG tubes as a biomaterial therapy to promote regeneration and functional recovery in SCI.

Bacterial nanocellulose (BNC) is a durable, flexible, and dynamic biomaterial capable of serving a wide variety of fields, sectors, and applications within biotechnology, healthcare, electronics, agriculture, fashion, and others. BNC is produced spontaneously in carbohydrate-rich bacterial culture media, forming a cellulosic pellicle via a nanonetwork of fibrils extruded from certain genera. Herein, we demonstrate engineering BNC-based scaffolds with tunable physical and mechanical properties through postprocessing. Human skeletal muscle myoblasts (HSMMs) were cultured on these scaffolds, and in vitro electrical stimulation was applied to promote cellular function for tissue engineering applications. We compared physiologic maturation markers of human skeletal muscle myoblast development using a 2.5-dimensional culture paradigm in fabricated BNC scaffolds, compared to two-dimensional (2D) controls. We demonstrate that the culture of human skeletal muscle myoblasts on BNC scaffolds developed under electrical stimulation produced highly aligned, physiologic morphology of human skeletal muscle myofibers compared to unstimulated BNC and standard 2D culture. Furthermore, we compared an array of metrics to assess the BNC scaffold in a rigorous head-to-head study with commercially available, clinically approved matrices, Kerecis Omega3 Wound Matrix (Marigen) and Phoenix as well as a gelatin methacryloyl (GelMA) hydrogel. The BNC scaffold outcompeted industry standard matrices as well as a 20% GelMA hydrogel in durability and sustained the support of human skeletal muscle myoblasts in vitro. This work offers a robust demonstration of BNC scaffold cytocompatibility with human skeletal muscle cells and sets the basis for future work in healthcare, bioengineering, and medical implant technological development.

Diamond-like Carbon (DLC) has been used as a coating material of choice for a variety of technological applications owing to its favorable bio-tribo-thermo-mechanical characteristics. Here, the possibility of bringing DLC into orthopedic joint implants is examined. With ever increasing number of patients suffering from osteoarthritis as well as with the ingress of the osteoarthritic joints malaise into younger and more active demographics, there is a pressing need to augment the performance and integrity of conventional total joint replacements (TJRs). Contemporary joint replacement devices use metal-on-polymer articulations to restore function to worn, damaged or diseased cartilage. The wear of polymeric components has been addressed using crosslinking and antioxidants; however, in the context of the metallic components, complications pertaining to corrosion and metal ion release inside the body still persist. Through this review article, we explore the use of DLC coatings on metallic bearing surfaces and elucidate why this technology might be a viable solution for ongoing electrochemical challenges in orthopedics. The different characteristics of DLC coatings and their feasibility in TJRs are examined through assessment of tribo-material characterization methods. A holistic characterization of the coating-substrate interface and the wear performance of such systems are discussed. As with all biomaterials used in TJRs, we need mindful consideration of potential in-vivo challenges. We present a few caveats for DLC coatings including delamination, hydrophobicity, and other conflicting as well as outdating findings in the literature. We recommend prudently exploring DLC films as potential coatings on metallic TJR components to solve the problems pertaining to wear, metal ion release, and corrosion. Ultimately, we advise bringing DLC into clinical use only after addressing all challenges and concerns outlined in this article.

Urethral conditions affect children and adults, increasing the risk of urinary tract infections, voiding and sexual dysfunction, and renal failure. Current tissue replacements differ from healthy urethral tissues in structural and mechanical characteristics, causing high risk of postoperative complications. 3D bioprinting can overcome these limitations through the creation of complex, layered architectures using materials with location-specific biomechanical properties. This review highlights prior research and describes the potential for these emerging technologies to address ongoing challenges in urethral tissue engineering, including biomechanical and structural mismatch, lack of individualized repair solutions, and inadequate wound healing and vascularization. In the future, the integration of 3D bioprinting technology with advanced biomaterials, computational modeling, and 3D imaging could transform personalized urethral surgical procedures.

The current paradigm of medicine is mostly designed to block or prevent pathological events. Once the disease-led tissue damage occurs, the limited endogenous regeneration may lead to depletion or loss of function for cells in the tissues. Cell therapy is rapidly evolving and influencing the field of medicine, where in some instances attempts to address cell loss in the body. Due to their biological function, engineerability, and their responsiveness to stimuli, cells are ideal candidates for therapeutic applications in many cases. Such promise is yet to be fully obtained as delivery of cells that functionally integrate with the desired tissues upon transplantation is still a topic of scientific research and development. Main known impediments for cell therapy include mechanical insults, cell viability, host's immune response, and lack of required nutrients for the transplanted cells. These challenges could be divided into three different steps: 1) Prior to, 2) during the and 3) after the transplantation procedure. In this review, we attempt to briefly summarize published approaches employing biomaterials to mitigate the above technical challenges. Biomaterials are offering an engineerable platform that could be tuned for different classes of cell transplantation to potentially enhance and lengthen the pharmacodynamics of cell therapies.

Peripheral artery disease is an atherosclerotic disease associated with limb ischemia that necessitates limb amputation in severe cases. Cell therapies comprised of adult mononuclear or stromal cells have been clinically tested and show moderate benefits. Bioengineering strategies can be applied to modify cell behavior and function in a controllable fashion. Using mechanically tunable or spatially controllable biomaterials, we highlight examples in which biomaterials can increase the survival and function of the transplanted cells to improve their revascularization efficacy in preclinical models. Biomaterials can be used in conjunction with soluble factors or genetic approaches to further modulate the behavior of transplanted cells and the locally implanted tissue environment in vivo. We critically assess the advances in bioengineering strategies such as 3-dimensional bioprinting and immunomodulatory biomaterials that can be applied to the treatment of peripheral artery disease and then discuss the current challenges and future directions in the implementation of bioengineering strategies.

An emerging cellular engineering method creates synthetic polymer matrices inside cells. By contrast with classical genetic, enzymatic, or radioactive techniques, this materials-based approach introduces non-natural polymers inside cells, thus modifying cellular states and functionalities. Here, we cover various materials and chemistries that have been exploited to create intracellular polymer matrices. In addition, we discuss emergent cellular properties due to the intracellular polymerization, including nonreplicating but active metabolism, maintenance of membrane integrity, and resistance to environmental stressors. We also discuss past work and future opportunities for developing and applying synthetic cells that contain intracellular polymers. The materials-based approach will usher in new applications of synthetic cells for broad biotechnological applications.

(1) Background: Collagen, a natural polymer, is widely used in the fabrication of membranes for guided bone regeneration (GBR). These membranes are sourced from various tissues, such as skin, pericardium, peritoneum, and tendons, which exhibit differences in regenerative outcomes. Therefore, this study aimed to evaluate the morphological and chemical properties of porcine collagen membranes from five different tissue sources: skin, pericardium, dermis, tendons, and peritoneum. (2) Methods: The membrane structure was analyzed using energy-dispersive X-ray spectrometry (EDX), variable pressure scanning electron microscopy (VP-SEM), Fourier transform infrared spectroscopy (FTIR), and thermal stability via thermogravimetric analysis (TGA). The absorption capacity of the membranes for GBR was also assessed using an analytical digital balance. (3) Results: The membranes displayed distinct microstructural features. Skin- and tendon-derived membranes had rough surfaces with nanopores (1.44 ± 1.24 µm and 0.46 ± 0.1 µm, respectively), while pericardium- and dermis-derived membranes exhibited rough surfaces with macropores (78.90 ± 75.89 µm and 64.89 ± 13.15 µm, respectively). The peritoneum-derived membrane featured a rough surface of compact longitudinal fibers with irregular macropores (9.02 ± 3.70 µm). The thickness varied significantly among the membranes, showing differences in absorption capacity. The pericardium membrane exhibited the highest absorption, increasing by more than 10 times its initial mass. In contrast, the skin-derived membrane demonstrated the lowest absorption, increasing by less than 4 times its initial mass. Chemical analysis revealed that all membranes were primarily composed of carbon, nitrogen, and oxygen. Thermogravimetric and differential scanning calorimetry analyses showed no significant compositional differences among the membranes. FTIR spectra confirmed the presence of collagen, with characteristic peaks corresponding to Amide A, B, I, II, and III. (4) Conclusions: The tissue origin of collagen membranes significantly influences their morphological characteristics, which may, in turn, affect their osteogenic properties. These findings provide valuable insights into the selection of collagen membranes for GBR applications. [ABSTRACT FROM AUTHOR]

The rapid advancement of 3D printing technology has revolutionized the fabrication of microneedle arrays (MNAs), which hold great promise in biomedical applications such as drug delivery, diagnostics, and therapeutic interventions. This review uniquely explores advanced materials used in the production of 3D-printed MNAs, including photopolymer resins, biocompatible materials, and composite resins, designed to improve mechanical properties, biocompatibility, and functional performance. Additionally, it introduces emerging trends such as 4D printing for programmable MNAs. By analyzing recent innovations, this review identifies critical challenges and proposes future directions to advance the field of 3D-printed MNAs. Unlike previous reviews, this paper emphasizes the integration of innovative materials with advanced 3D printing techniques to enhance both the performance and sustainability of MNAs. [ABSTRACT FROM AUTHOR]

The aim of this systematic review was to assess the antimicrobial effectiveness of silver nanoparticles (AgNPs) incorporated to different orthodontic bonding systems. Additionally, the review investigated the impact of AgNPs on the bonding properties of these materials. The hypothesis posed that the addition of AgNPs would enhance the antimicrobial efficacy of orthodontic bonding systems while maintaining their bonding properties. The systematic review employed a PICO-based search strategy, targeting in vitro studies focusing on the integration of nano silver particles into orthodontic bonding systems with potential antimicrobial activity. The intervention involved the use of nano silver in orthodontic bonding systems, with a comparison to systems lacking nano silver. The primary outcomes assessed were antimicrobial activity and shear bond strength (SBS). The search process, conducted without publication date restrictions, yielded 551 potential articles: 34 from PubMed, 360 from PubMed Central, 42 from Embase, 54 from Scopus, and 61 from Web of Science. Ultimately, a qualitative synthesis was conducted on 13 papers. The PRISMA diagram, visually represented the search strategy, screening process, and inclusion criteria. The study protocol was registered in PROSPERO CRD42023487656 to enhance transparency and adherence to systematic review guidelines. Quality assessment of the included studies was performed using the Newcastle-Ottawa Scale, revealing that the 13 articles meeting the inclusion criteria demonstrated a high level of evidence. Seven studies were included in the meta-analysis regarding shear bond strength. In summary, the synthesized findings from these studies strongly underscore the promising potential of orthodontic materials modified with AgNPs. These materials exhibit effective resistance against cariogenic bacteria without compromising bonding properties below clinical acceptability. Such innovative materials hold significant implications for advancing oral health within the realm of orthodontics. [ABSTRACT FROM AUTHOR]

In recent years, there has been extensive research into drug delivery systems aimed at enhancing drug utilization while minimizing drug toxicities. Among these systems, oral patches/films have garnered significant attention due to their convenience, noninvasive administration, ability to bypass hepatic first‐pass metabolism, thereby enhancing drug bioavailability, and their potential to ensure good compliance, particularly among special patient populations. In this review, from the perspective of the anatomical characteristics of the oral cavity and the advantages and difficulties of oral drug delivery, we illustrate the design ideas, manufacturing techniques, research methodologies, and the essential attributes of an ideal oral patch/film. Furthermore, the applications of oral patches/films in both localized and systemic drug delivery were discussed. Finally, we offer insights into the future prospects of the oral patch/film, aiming to provide valuable reference for the advancement of oral localized drug delivery systems. [ABSTRACT FROM AUTHOR]

Abstract The aim of this systematic review was to assess the antimicrobial effectiveness of silver nanoparticles (AgNPs) incorporated to different orthodontic bonding systems. Additionally, the review investigated the impact of AgNPs on the bonding properties of these materials. The hypothesis posed that the addition of AgNPs would enhance the antimicrobial efficacy of orthodontic bonding systems while maintaining their bonding properties. The systematic review employed a PICO-based search strategy, targeting in vitro studies focusing on the integration of nano silver particles into orthodontic bonding systems with potential antimicrobial activity. The intervention involved the use of nano silver in orthodontic bonding systems, with a comparison to systems lacking nano silver. The primary outcomes assessed were antimicrobial activity and shear bond strength (SBS). The search process, conducted without publication date restrictions, yielded 551 potential articles: 34 from PubMed, 360 from PubMed Central, 42 from Embase, 54 from Scopus, and 61 from Web of Science. Ultimately, a qualitative synthesis was conducted on 13 papers. The PRISMA diagram, visually represented the search strategy, screening process, and inclusion criteria. The study protocol was registered in PROSPERO CRD42023487656 to enhance transparency and adherence to systematic review guidelines. Quality assessment of the included studies was performed using the Newcastle-Ottawa Scale, revealing that the 13 articles meeting the inclusion criteria demonstrated a high level of evidence. Seven studies were included in the meta-analysis regarding shear bond strength. In summary, the synthesized findings from these studies strongly underscore the promising potential of orthodontic materials modified with AgNPs. These materials exhibit effective resistance against cariogenic bacteria without compromising bonding properties below clinical acceptability. Such innovative materials hold significant implications for advancing oral health within the realm of orthodontics.

Biomaterial wound dressings, such as hydrogels, interact with host cells to regulate tissue repair. This study investigates how crosslinking of gelatin-based hydrogels influences immune and stromal cell behavior and wound healing in female mice. We observe that softer, lightly crosslinked hydrogels promote greater cellular infiltration and result in smaller scars compared to stiffer, heavily crosslinked hydrogels. Using single-cell RNA sequencing, we further show that heavily crosslinked hydrogels increase inflammation and lead to the formation of a distinct macrophage subpopulation exhibiting signs of oxidative activity and cell fusion. Conversely, lightly crosslinked hydrogels are more readily taken up by macrophages and integrated within the tissue. The physical properties differentially affect macrophage and fibroblast interactions, with heavily crosslinked hydrogels promoting pro-fibrotic fibroblast activity that drives macrophage fusion through RANKL signaling. These findings suggest that tuning the physical properties of hydrogels can guide cellular responses and improve healing, offering insights for designing better biomaterials for wound treatment.

The field of hybrid engineered living materials seeks to pair living organisms with synthetic materials to generate biocomposite materials with augmented function since living systems can provide highly-programmable and complex behavior. Engineered living materials have typically been fabricated using techniques in benign aqueous environments, limiting their application. In this work, biocomposite fabrication is demonstrated in which spores from polymer-degrading bacteria are incorporated into a thermoplastic polyurethane using high-temperature melt extrusion. Bacteria are engineered using adaptive laboratory evolution to improve their heat tolerance to ensure nearly complete cell survivability during manufacturing at 135 °C. Furthermore, the overall tensile properties of spore-filled thermoplastic polyurethanes are substantially improved, resulting in a significant improvement in toughness. The biocomposites facilitate disintegration in compost in the absence of a microbe-rich environment. Finally, embedded spores demonstrate a rationally programmed function, expressing green fluorescent protein. This research provides a scalable method to fabricate advanced biocomposite materials in industrially-compatible processes.

Bioelectronic Medicine stands as an emerging field that rapidly evolves and offers distinctive clinical benefits, alongside unique challenges. It consists of the modulation of the nervous system by precise delivery of electrical current for the treatment of clinical conditions, such as post-stroke movement recovery or drug-resistant disorders. The unquestionable clinical impact of Bioelectronic Medicine is underscored by the successful translation to humans in the last decades, and the long list of preclinical studies. Given the emergency of accelerating the progress in new neuromodulation treatments (i.e., drug-resistant hypertension, autoimmune and degenerative diseases), collaboration between multiple fields is imperative. This work intends to foster multidisciplinary work and bring together different fields to provide the fundamental basis underlying Bioelectronic Medicine. In this review we will go from the biophysics of the cell membrane, which we consider the inner core of neuromodulation, to patient care. We will discuss the recently discovered mechanism of neurotransmission switching and how it will impact neuromodulation design, and we will provide an update on neuronal and glial basis in health and disease. The advances in biomedical technology have facilitated the collection of large amounts of data, thereby introducing new challenges in data analysis. We will discuss the current approaches and challenges in high throughput data analysis, encompassing big data, networks, artificial intelligence, and internet of things. Emphasis will be placed on understanding the electrochemical properties of neural interfaces, along with the integration of biocompatible and reliable materials and compliance with biomedical regulations for translational applications. Preclinical validation is foundational to the translational process, and we will discuss the critical aspects of such animal studies. Finally, we will focus on the patient point-of-care and challenges in neuromodulation as the ultimate goal of bioelectronic medicine. This review is a call to scientists from different fields to work together with a common endeavor: accelerate the decoding and modulation of the nervous system in a new era of therapeutic possibilities.

Hollow vaterite microspheres are important materials for biomedical applications such as drug delivery and regenerative medicine owing to their biocompatibility, high specific surface area, and ability to encapsulate a large number of bioactive molecules and compounds. We demonstrated that hollow vaterite microspheres are produced by an Escherichia coli strain engineered with a urease gene cluster from the ureolytic bacteria Sporosarcina pasteurii in the presence of bovine serum albumin. We characterized the 3D nanoscale morphology of five biogenic hollow vaterite microspheres using 3D high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) tomography. Using automated high-throughput HAADF-STEM imaging across several sample tilt orientations, we show that the microspheres evolved from a smaller more ellipsoidal shape to a larger more spherical shape while the internal hollow core increased in size and remained relatively spherical, indicating that the microspheres produced by this engineered strain likely do not contain the bacteria. The statistical 3D morphology information demonstrates the potential for using biogenic calcium carbonate mineralization to produce hollow vaterite microspheres with controlled morphologies. STATEMENT OF SIGNIFICANCE: The nanoscale 3D structures of biomaterials determine their physical, chemical, and biological properties, however significant efforts are required to obtain a statistical understanding of the internal 3D morphology of materials without damaging the structures. In this study, we developed a non-destructive, automated technique that allows us to understand the nanoscale 3D morphology of many unique hollow vaterite microspheres beyond the spectroscopy methods that lack local information and microscopy methods that cannot interrogate the full 3D structure. The method allowed us to quantitatively correlate the external diameters and aspect ratios of vaterite microspheres with their hollow internal structures at the nanoscale. This work demonstrates the opportunity to use automated transmission electron microscopy to characterize nanoscale 3D morphologies of many biomaterials and validate the chemical and biological functionality of these materials.

The biofunctionalization of synthetic materials has extensive utility for biomedical applications, but approaches to bioconjugation typically show insufficient efficiency and controllability. We recently developed an approach by building synthetic DNA scaffolds on biomaterial surfaces that enables the precise control of cargo density and ratio, thus improving the assembly and organization of functional cargos. We used this approach to show that the modulation and phenotypic adaptation of immune cells can be regulated using our precisely functionalized biomaterials. Here, we describe the three key procedures, including the fabrication of polymeric particles engrafted with short DNA scaffolds, the attachment of functional cargos with complementary DNA strands, and the surface assembly control and quantification. We also explain the critical checkpoints needed to ensure the overall quality and expected characteristics of the biological product. We provide additional experimental design considerations for modifying the approach by varying the material composition, size or cargo types. As an example, we cover the use of the protocol for human primary T cell activation and for the identification of parameters that affect ex vivo T cell manufacturing. The protocol requires users with diverse expertise ranging from synthetic materials to bioconjugation chemistry to immunology. The fabrication procedures and validation assays to design high-fidelity DNA-scaffolded biomaterials typically require 8 d.

Abstract Background The deformation of oral and maxillofacial region leads to not only the damage of morphology and function, but also a series of aesthetic and psychological problems, severely affecting the quality of life of patients. Oral tissue engineering refers to developing biomaterials for repair or regeneration, with the application of tissue engineering technologies. This has become an area of increasing prominence. Current biologically inert materials are insufficient to fulfill clinical requirements. Therefore, tissue-engineered biomaterials with bioactive, even bionic properties are desperately needed. Main body The complexity of the anatomy and the diversity of tissue types of oral and maxillofacial region pose great challenges to the regeneration, in the aspects of both biomaterials and manufacturing technologies. Biomaterials in clinical practice or research have evolved from natural materials to synthetic materials, from homogeneous materials to multiple composite materials. And now composite materials have increasingly demonstrated their advantages in terms of physicochemical and biological properties over conventional materials. In terms of manufacturing, traditional coating, sintering, and milling technologies can no longer satisfy the requirements for high-precision bionic structures of oral-tissue-engineering biomaterials. Scientists have turned to biofabrication technologies such as microfluidics and additive manufacturing. Short conclusion This review aims to summarize the noteworthy advancements made in biomaterials of oral tissue engineering. We outlined the current biomaterials and manufacturing technologies and focused on various applications of these materials that may be connected to clinical treatment and research. We also suggested the future direction of development for biomaterials in oral tissue engineering. In future, biomaterials characterized by precision, functionalization, and individualization will be manufactured through digital, microfluidic, and 3D printing technologies. Graphical abstract

The drive for minimally invasive endodontic treatment strategies has shifted focus from technically complex and destructive root canal treatments towards more conservative vital pulp treatment. However, novel approaches to maintaining dental pulp vitality after disease or trauma will require the development of innovative, biologically-driven regenerative medicine strategies. For example, cell-homing and cell-based therapies have recently been developed in vitro and trialled in preclinical models to study dental pulp regeneration. These approaches utilise natural and synthetic scaffolds that can deliver a range of bioactive pharmacological epigenetic modulators (HDACis, DNMTis, and ncRNAs), which are cost-effective and easily applied to stimulate pulp tissue regrowth. Unfortunately, many biological factors hinder the clinical development of regenerative therapies, including a lack of blood supply and poor infection control in the necrotic root canal system. Additional challenges include a need for clinically relevant models and manufacturing challenges such as scalability, cost concerns, and regulatory issues. This review will describe the current state of bioactive-biomaterial/scaffold-based engineering strategies to stimulate dentine-pulp regeneration, explicitly focusing on epigenetic modulators and therapeutic pharmacological inhibition. It will highlight the components of dental pulp regenerative approaches, describe their current limitations, and offer suggestions for the effective translation of novel epigenetic-laden bioactive materials for innovative therapeutics.

Abstract Mineral Trioxide Aggregate (MTA) is the gold standard for vital pulp treatment (VPT), but its superiority over novel calcium silicate-based cements in permanent teeth lacks systematic evidence. This study aimed to compare the efficacy of these materials in VPT through a network meta-analysis. A systematic search was conducted in MEDLINE, EMBASE, Cochrane Library, and Web of Science until January 20, 2024. The inclusion criteria were randomized controlled trials involving VPT with biomaterials and reversible or irreversible pulpitis diagnoses in mature permanent teeth. The primary outcome was the odds ratio (OR) of failure rates with 95% confidence intervals. In the 21 eligible trials, failure rates were significantly higher with calcium-hydroxide than MTA at six (OR 2.26 [1.52-3.36]), 12 (OR 2.53 [1.76-3.62]), and 24 months (OR 2.46 [1.60-3.79]). Failure rates for Totalfill at six (OR 1.19 [0.55-2.58]) and 12 months (OR 1.43 [0.71-2.92]), and Biodentine at six (OR 1.09 [0.66-1.78]), 12 (OR 1.21 [0.74-1.96]), and 24 months (OR 1.47 [0.81-2.68]) were not significantly different from MTA. The results were similar in the direct pulp capping subgroup, whereas, in the partial and full pulpotomy subgroup, there was not enough evidence to achieve significant differences. MTA, Biodentine, and Totalfill are the most efficient materials for VPT. However, calcium-hydroxide-based materials are not recommended in VPT.

ABSTRACT Background Aims Methods Results Conclusions Hyaluronic acid (HA) fillers are widely used in aesthetic medicine, but their in vivo behavior and long‐term effects are not fully understood.To review the decomposition and changes occurring in the body following HA filler injections, focusing on crosslinking agents, degradation processes, and tissue responses.This review analyzed oxidative and enzymatic degradation processes of HA fillers, evaluated the impact of 1,4‐Butanediol Diglycidyl Ether (BDDE) crosslinking, and examined histological changes post‐injection.Uncrosslinked HA degrades rapidly due to endogenous hyaluronidase, while crosslinked HA undergoes slower degradation via free radicals and hyaluronidase. Complete cross‐linking (C‐MoD) showed better durability compared to partially cross‐linked BDDE (P‐MoD). The concept of modification efficiency (MoE) was proposed to optimize filler safety and viscoelastic properties. Histological analysis revealed collagen capsule formation and autologous tissue replacement, affecting long‐term outcomes. The degree of chemical modification (MoD) influences filler durability and safety, with concerns raised about potential delayed immune reactions from accumulated pendent BDDE.Clinicians should consider injection site, tissue conditions, and filler properties for safe and effective HA filler use. Emphasizing thorough BDDE removal and optimal crosslinking can enhance treatment safety and efficacy. The balance between achieving desired viscoelastic properties and minimizing potential risks is crucial. Future studies should include diverse ethnic groups to validate findings and further explore long‐term tissue responses to HA fillers. [ABSTRACT FROM AUTHOR]

Clear aligner therapy is a rapidly developing orthodontic treatment. 3D-printing technology, which enables the creation of complex geometric structures with high precision, has been used in dentistry. This article aims to summarize the various aspects of 3D-printing clear aligners and give an outlook on their future development. The traditional thermoforming technology is introduced and the principle and application of 3D-printed clear aligners and materials are introduced, as well as the application prospects of 3D-printed clear aligners. According to PRISMA statement, the relevant literature of 3D-printing clear aligner was searched in PubMed, Web of Science, Embase and other databases. We searched the related words in the MESH database and then carried out advanced searches. We read systematic review and conference papers to find the articles related to the subject and manually added and excluded articles by reading the title and abstract. The production of clear aligners combines computer-aided 3D analysis, personalized design and digital molding technology. The thickness and edges of the 3D-printed clear aligner can be digitally controlled, which allows appliance more efficiently fitted. Presently, the array of clear resins suitable for 3D-printing include photo polymeric clear methacrylate-based resin (Dental LT) (Form Labs, Somerville, Mass), aliphatic vinyl ester-polyurethane polymer (Tera Harz TC-85) (Graphy, Seoul, South Korea). They all have good biocompatibility. But no such material is currently approved on the market. Developing biocompatible resins and further improving the material's mechanical properties will be critical for the combination of 3Dprinting and clear aligners. However, the literature on 3D-printed clear aligners is limited and lacks clinical application. Further in vivo and in vitro tests, as well as additional exploration in conjunction with corresponding cytological tests, are required for the research on available materials and machinery for 3D-printing clear aligners. [ABSTRACT FROM AUTHOR]

Background: The deformation of oral and maxillofacial region leads to not only the damage of morphology and function, but also a series of aesthetic and psychological problems, severely affecting the quality of life of patients. Oral tissue engineering refers to developing biomaterials for repair or regeneration, with the application of tissue engineering technologies. This has become an area of increasing prominence. Current biologically inert materials are insufficient to fulfill clinical requirements. Therefore, tissue-engineered biomaterials with bioactive, even bionic properties are desperately needed. Main body: The complexity of the anatomy and the diversity of tissue types of oral and maxillofacial region pose great challenges to the regeneration, in the aspects of both biomaterials and manufacturing technologies. Biomaterials in clinical practice or research have evolved from natural materials to synthetic materials, from homogeneous materials to multiple composite materials. And now composite materials have increasingly demonstrated their advantages in terms of physicochemical and biological properties over conventional materials. In terms of manufacturing, traditional coating, sintering, and milling technologies can no longer satisfy the requirements for high-precision bionic structures of oral-tissue-engineering biomaterials. Scientists have turned to biofabrication technologies such as microfluidics and additive manufacturing. Short conclusion: This review aims to summarize the noteworthy advancements made in biomaterials of oral tissue engineering. We outlined the current biomaterials and manufacturing technologies and focused on various applications of these materials that may be connected to clinical treatment and research. We also suggested the future direction of development for biomaterials in oral tissue engineering. In future, biomaterials characterized by precision, functionalization, and individualization will be manufactured through digital, microfluidic, and 3D printing technologies. [ABSTRACT FROM AUTHOR]

Introduction: Calcium silicate-based sealers are an alternative to be used into root canal, mainly to their biological properties. However, some biological parameters need to be determined in an in vivo animal research model. So, the aim of the present study was to evaluate in vivo the tissue biocompatibility of a calcium silicate-based sealer (EndoSequence BC Sealer) and an epoxy resin-based sealer (AH-Plus). Materials and Methods: Polyethylene tubes were filled with freshly mixed sealers and implanted in connective subcutaneous tissue of 25 rats (5/euthanasia day) (Rattus norvegicus albinus). Empty tubes were used as controls and no tubes as sham. Histopathological (hematoxylin eosin) and histochemical (Picrosirius red) examinations were conducted at 3, 7, 15, 30 and 60 days (five rats/day) after the implantation procedure (n=5/group). The type/intensity of inflammation and collagenesis was analyzed statistically with Friedman or Kruskal-Wallis/Dunn tests (P<0.05). Results: The profile of inflammation induced by AH-Plus (Median=2, Range=2-3) was significantly greater than that by Endosequence BC Sealer (Median=1, Range=1-1) during the 15-day experimentation period (P=0.018). After 30 days, both materials produced similar tissue reaction (P>0.05). AH-Plus and Endosequence BC Sealer (Median=2, Range=1-2) induced a high level of fibrosis after 60-day than control (Median=1, Range=1-1) and sham (Median=0, Range=0-0) groups (P<0.001) of fibrosis based in type I collagen increase (P=0.025 and P=0.021, respectively). Tissue necrosis was not observed and the bioceramic sealer showed significant signs of endocytosed (Median=1, Range=1-1) material after 7 days than other groups (Median=0, Range=0-0) (P<0.05). The calcium silicate-based sealer induced tissue repair faster than the epoxy resin-based sealer tested. However, both materials showed adequate biocompatibility and tolerance by subcutaneous tissues, with few differences in inflammatory profiles, formation of granulation tissue, and collagenesis. Conclusions: It may be concluded that calcium silicate-based sealer (EndoSequence BC Sealer) and an epoxy resin-based sealer (AH-Plus) presented suitable biocompatibility. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to systematically review the safety and effectiveness of the injectable biostimulators dermal fillers calcium hydroxyapatite (CaHA) and polycaprolactone (PCL) in facial esthetic procedures. Materials and Methods: Comprehensive electronic searches were executed across six academic databases. The primary outcome focused on safety by examining studies that reported the incidence of adverse events (AEs). The secondary outcome gauged the satisfaction of the patients and injectors by validated esthetic scales. To evaluate biases, the Joanna Briggs Institute Checklist tools were employed. Results: We included a total of 79 studies. In the quantitative assessment of the CaHA, out of 5032 injected patients, 21.8% manifested early AEs, 0.85% experienced delayed reactions, and 0.27% had severe complications. Within the PCL group, consisting of 1119 patients, 83.3% exhibited early AEs, 5.6% had delayed reactions, and none had serious complications. Regarding esthetic satisfaction outcome, both products presented favorable results, but a limited number of studies assessed these data. In the studies evaluated qualitatively, a broad array of AEs were cataloged. Conclusions: The occurrence of serious AEs associated with CaHA and PCL fillers is relatively low. Both CaHA and PCL fillers exhibit favorable safety profiles, with most AEs being transient in nature. [ABSTRACT FROM AUTHOR]

Poly-d,l-lactic acid (PDLLA) is a biodegradable and biocompatible polymer that has garnered significant attention in dermatology due to its unique properties and versatile applications. This literature review offers a comprehensive analysis of PDLLA's roles in various dermatological conditions and wound-healing applications. PDLLA demonstrates significant benefits in enhancing skin elasticity and firmness, reducing wrinkles, and promoting tissue regeneration and scar remodeling. Its biodegradable properties render it highly suitable for soft tissue augmentation, including facial and breast reconstruction. We discuss the critical importance of understanding PDLLA's physical and chemical characteristics to optimize its performance and safety, with a focus on how nano- and micro-particulate systems can improve delivery and stability. While potential complications, such as granuloma formation and non-inflammatory nodules, are highlighted, effective monitoring and early intervention strategies are essential. PDLLA's applications extend beyond dermatology into orthopedics and drug delivery, owing to its superior mechanical stability and biocompatibility. This review underscores the need for ongoing research to fully elucidate the mechanisms of PDLLA and to maximize its therapeutic potential across diverse medical fields. [ABSTRACT FROM AUTHOR]

Background: Numerous studies have focused on skin damage, the most prevalent physical injury, aiming to improve wound healing. The exploration of biomaterials, specifically eggshell membranes (ESMs), is undertaken to accelerate the recovery of skin injuries. The membrane must be separated from the shell to make this biomaterial usable. Hence, this investigation aimed to identify more about the methods for membrane isolation and determine the most efficient one for usage as a biomaterial. Methods and materials: For this purpose, ESM was removed from eggs using different protocols (with sodium carbonate, acetic acid, HCl, calcium carbonate, and using forceps for separation). Consequently, we have examined the membranes' mechanical and morphological qualities. Results: According to the analysis of microscopic surface morphology, the membranes have appropriate porosity. MTT assay also revealed that the membranes have no cytotoxic effect on 3T3 cells. The results indicated that the ESM had acquired acceptable coagulation and was compatible with blood. Based on the obtained results, Provacol 4 (0.5‐mol HCl and neutralized with 0.1‐mol NaOH) was better than other methods of extraction and eggshell separation because it was more cell‐compatible and more compatible with blood. Conclusion: This study demonstrates that ESMs can be used as a suitable biomaterial in medical applications. [ABSTRACT FROM AUTHOR]

The objective of the present study was to evaluate the carbon fiber obtained from textile PAN fiber, in its different forms, as a potential scaffolds synthetic bone. Thirty‐four adult rats were used (Rattus norvegicus, albinus variation), two critical sized bone defects were made that were 5 mm in diameter. Twenty‐four animals were randomly divided into four groups: control (C)—bone defect + blood clot, non‐activated carbon fiber felt (NACFF)—bone defect + NACFF, activated carbon fiber felt (ACFF)—bone defect + ACFF, and silver activated carbon fiber felt (Ag‐ACFF)—bone defect + Ag‐ACFF, and was observed by 15 and 60 days for histomorphometric, three‐dimensional computerized microtomography (microCT) and mineral apposition analysis. On histomorphometric and microCT analyses, NACFF were associated with higher proportion of neoformed bone and maintenance of bone structure. On fluorochrome bone label, there was no differences between the groups. NACFF has shown to be a promising synthetic material as a scaffold for bone regeneration. [ABSTRACT FROM AUTHOR]

Biocompatible Mg–2Zn–1Ca–0.3Mn is synthesized using the disintegrated metal deposition process and subjected to two types of cryogenic treatments (refrigeration [RF] at −20 and −196 °C using liquid nitrogen) with a target to improve microstructural, thermal, mechanical, and electrochemical responses. The material exhibits densification and grain refinement after these treatments, which improves the physical, thermal, compressive, and corrosion responses. While both RF and liquid nitrogen exposures improve the overall combination of properties, overall improvement in properties is best met with RF treatment at −20 °C. In the results of this work, the efficacy of low energy option (RF) is convincingly established rather than liquid nitrogen exposure (as conventionally practiced) to enhance microstructure and properties. [ABSTRACT FROM AUTHOR]

Mineral Trioxide Aggregate (MTA) is the gold standard for vital pulp treatment (VPT), but its superiority over novel calcium silicate-based cements in permanent teeth lacks systematic evidence. This study aimed to compare the efficacy of these materials in VPT through a network meta-analysis. A systematic search was conducted in MEDLINE, EMBASE, Cochrane Library, and Web of Science until January 20, 2024. The inclusion criteria were randomized controlled trials involving VPT with biomaterials and reversible or irreversible pulpitis diagnoses in mature permanent teeth. The primary outcome was the odds ratio (OR) of failure rates with 95% confidence intervals. In the 21 eligible trials, failure rates were significantly higher with calcium-hydroxide than MTA at six (OR 2.26 [1.52-3.36]), 12 (OR 2.53 [1.76-3.62]), and 24 months (OR 2.46 [1.60-3.79]). Failure rates for Totalfill at six (OR 1.19 [0.55-2.58]) and 12 months (OR 1.43 [0.71-2.92]), and Biodentine at six (OR 1.09 [0.66-1.78]), 12 (OR 1.21 [0.74-1.96]), and 24 months (OR 1.47 [0.81-2.68]) were not significantly different from MTA. The results were similar in the direct pulp capping subgroup, whereas, in the partial and full pulpotomy subgroup, there was not enough evidence to achieve significant differences. MTA, Biodentine, and Totalfill are the most efficient materials for VPT. However, calcium-hydroxide-based materials are not recommended in VPT. [ABSTRACT FROM AUTHOR]

Objectives: This study attempted to develop 2 biodegradable periodontal chips containing Salvadora persica (miswak) or benzyl isothiocyanate (BITC) extracts and evaluate their clinical effectiveness in managing periodontitis. Methods: This clinical trial was conducted at the Faculty of Dentistry, Universiti Teknologi MARA Shah Alam, Selangor, Malaysia, from September 2010 to April 2012. Periodontal chips were formulated using S. persica, benzyl isothiocyanate (BITC) and chitosan extracts. All patients were treated with full mouth scaling and root planing at baseline. Thereafter, the periodontal pockets (=5 mm in length) were divided into 4 groups: the control group; group 2 (plain chitosan chip); group 3 (S. persica extract); and group 4 (BITC extract). Plaque index (PI), bleeding on probing (BOP), periodontal probing pocket depth and clinical attachment levels were recorded at days 0 and 60 only. Results: A total of 12 patients participated in this study. Overall, 240 periodontal pockets were evaluated. The study revealed significant improvements in PI, BOP and reduction in periodontal pocket depth in all 4 groups (P <0.05). The improvement in clinical attachment level was significantly higher (P <0.001) among the group that received S. persica chips compared to the control and other chip-treated groups. Conclusion: Periodontal chips containing S. persica can be used as adjuncts to treat patients with periodontitis. [ABSTRACT FROM AUTHOR]

This manuscript describes the development and characterization of electrospun nanofibers incorporating bioactive hydrolysates obtained from the microbial bioconversion of feathers, a highly available agro-industrial byproduct. The electrospun nanofibers were characterized using different instrumental methods, and their antioxidant properties and toxicological potential were evaluated. Keratin hydrolysates (KHs) produced by Bacillus velezensis P45 were incorporated at 1, 2.5, and 5% (w/w) into poly-ε-caprolactone (PCL; 10 and 15%, w/v solutions) before electrospinning. The obtained nanofibers were between 296 and 363 nm in diameter, showing a string-like morphology and adequate structural continuity. Thermogravimetric analysis showed three weight loss events, with 5% of the mass lost up to 330 °C and 90% from 350 to 450 °C. Infrared spectroscopy showed typical peaks of PCL and amide bands corresponding to keratin peptides. The biological activity was preserved after electrospinning and the hemolytic activity was below 1% as expected for biocompatible materials. In addition, the antioxidant capacity released from the nanofibers was confirmed by DPPH and ABTS radical scavenging activities. The DPPH scavenging activity observed for the nanofibers was greater than 30% after 24 h of incubation, ranging from 845 to 1080 µM TEAC (Trolox equivalent antioxidant capacity). The antioxidant activity for the ABTS radical assay was 44.19, 49.61, and 56.21% (corresponding to 972.0, 1153.3, and 1228.7 µM TEAC) for nanofibers made using 15% PCL with 1, 2.5, and 5% KH, respectively. These nanostructures may represent interesting antioxidant biocompatible materials for various pharmaceutical applications, including wound dressings, topical drug delivery, cosmetics, and packaging. [ABSTRACT FROM AUTHOR]

An urgent issue is the preservation or reconstruction of the volume of bone tissue in planning and surgical treatment in the fields of medicine, such as traumatology, orthopedics, maxillofacial surgery and dentistry. After tooth extraction, resorption of the bone tissue of the alveolar crest of the jaws occurs, which must either be further eliminated by performing additional operations or using osteoplastic material for socket preservation at the extraction stage. Background and Objectives: The aim of the study was a comparative analysis of various osteoplastic materials used to preserve the volume of bone tissue in the preimplantation period. Materials and Methods: As part of the study, 80 patients were treated, who underwent socket preservation using xenografts, plasma enriched with growth factors, an autologous dentin matrix (ADM) and hydroxyapatite. Results: The results of the treatment 16 weeks after removal were comprehensively analyzed using a morphometric analysis of the bone's volume, cone beam tomography and morphological examination of burr biopsy specimens, as well as by determining the stability of the installed implant at different stages of treatment. Conclusions: The lowest level of bone tissue resorption according to the CBCT data was noted in the ADM and xenograft groups. It should be noted that the use of osteoplastic material in jaw surgery when reconstructing alveolar defects is an essential procedure for preventing the atrophy of bone tissue. [ABSTRACT FROM AUTHOR]

Cells are known to perceive their microenvironment through extracellular and intracellular mechanical signals. Upon sensing mechanical stimuli, cells can initiate various downstream signaling pathways that are vital to regulating proliferation, growth, and homeostasis. One such physiologic activity modulated by mechanical stimuli is osteogenic differentiation. The process of osteogenic mechanotransduction is regulated by numerous calcium ion channels-including channels coupled to cilia, mechanosensitive and voltage-sensitive channels, and channels associated with the endoplasmic reticulum. Evidence suggests these channels are implicated in osteogenic pathways such as the YAP/TAZ and canonical Wnt pathways. This review aims to describe the involvement of calcium channels in regulating osteogenic differentiation in response to mechanical loading and characterize the fashion in which those channels directly or indirectly mediate this process. The mechanotransduction pathway is a promising target for the development of regenerative materials for clinical applications due to its independence from exogenous growth factor supplementation. As such, also described are examples of osteogenic biomaterial strategies that involve the discussed calcium ion channels, calcium-dependent cellular structures, or calcium ion-regulating cellular features. Understanding the distinct ways calcium channels and signaling regulate these processes may uncover potential targets for advancing biomaterials with regenerative osteogenic capabilities.

All-liquid molding can be used to transform a liquid into free-form solid constructs, while maintaining internal fluidity. Traditional biological scaffolds, such as cured pre-gels, are normally processed in solid state, sacrificing flowability and permeability. However, it is essential to maintain the fluidity of the scaffold to truly mimic the complexity and heterogeneity of natural human tissues. Here, this work molds an aqueous biomaterial ink into liquid building blocks with rigid shapes while preserving internal fluidity. The molded ink blocks for bone-like vertebrae and cartilaginous-intervertebral-disc shapes, are magnetically manipulated to assemble into hierarchical structures as a scaffold for subsequent spinal column tissue growth. It is also possible to join separate ink blocks by interfacial coalescence, different from bridging solid blocks by interfacial fixation. Generally, aqueous biomaterial inks are molded into shapes with high fidelity by the interfacial jamming of alginate surfactants. The molded liquid blocks can be reconfigured using induced magnetic dipoles, that dictated the magnetic assembly behavior of liquid blocks. The implanted spinal column tissue exhibits a biocompatibility based on in vitro seeding and in vivo cultivating results, showing potential physiological function such as bending of the spinal column.

ABSTRACT Purpose: The surgical glue is widely used in closing cutaneous surgical wounds. Corticosteroids are indicated for their anti-inflammatory and immunomodulatory properties. The present work evaluated the pharmacological effects of triamcinolone (AT) incorporated into surgical glue (C) on the initial phase of the wound healing process in Wistar rats. Methods: Through in-vivo studies, the effects of the healing process, C or C+AT in the same rat were evaluated for seven and 14 days post-surgery. Results: The C+AT association did not change the physicochemical properties of the polymer. This association in wound healing confirmed the anti-inflammatory and immunomodulatory effects of the corticosteroid, with less neovascularization and fibrosis, in addition to the remodeling of the extracellular matrix carried out by the balance of myofibroblasts and less dense collagen fibers, culminating in tissue regeneration and possible reduction of side effects. Conclusion: This association is a powerful and innovative pharmacological tool, promising in translational medicine.

ABSTRACT Purpose: To evaluate the association of collagen gel with F18 bioactive glass (BG) in the healing of non-contaminated cutaneous wounds induced in healthy Wistar rats. Methods: One hundred twelve adult and healthy Wistar rats were randomly divided into four groups (n = 28): saline solution (0.9%); healing ointment based on allantoin and zinc oxide; collagen gel; and association of F18 BG powder and collagen gel. All the rats underwent the creation of a 3-cm diameter wound in their dorsal region. Macroscopic, thermographic, and tensiometric evaluations of the wound were performed. Results: The presence of granulation tissue varied significantly in and between the groups. The surface temperature assessed through thermography of wounds treated with saline solution (0.9%) increased significantly over time and between the groups. No difference was identified regarding tensiometry. Conclusions: Collagen gel associated with F18 BG induced beneficial healing effects on non-contaminated cutaneous wounds in Wistar rats, which included the induction of increased blood perfusion as assessed through thermography.

Abstract This study aimed to evaluate the efficacy of a xenogeneic collagen matrix (XCM) in treating gingival recessions (GR) in a thin gingival phenotype. This double-blind, planned, controlled, split-mouth clinical trial included 30 patients with bilateral recessions, randomly assigned to a test group (extended flap + XCM) and a control group (extended flap + connective tissue graft; CTG). Root coverage at 18 months was 1.75 ± 0.8 mm (72.9%) and 2.4 ± 0.51 mm (88.9%) in the test and the control groups, respectively. The upper limit of the confidence interval was not greater than the non-inferiority margin of 0.69 mm. The increase in gingival thickness was greater for autogenous graft (p = 0.003). Both treatments improved quality of life at 18 months. The keratinized tissue width (KTW) increased significantly in the grafted teeth, in both the test (p < 0.001) and the control groups (p < 0.001). Total root coverage was similar in both groups, reaching 70% and 66.7% in the control and test groups, respectively, with no significant differences observed for partial or complete root coverage (CRC). An association was observed in the quality of the gingival phenotype at 18 months according to the treatment group, i.e., a higher percentage of cases with a thicker phenotype was observed in the control group (86.7%), compared with the test group (53.3%) (p = 0.005). XCM was effective in treating GR, but CTG had better results because of significantly increased gingival thickness and phenotypic conversion.

Abstract Introduction For a successful implant-supported rehabilitation and long-term maintenance in the anterior maxilla, it is imperative that the patient possesses adequate bone quality and quantity. Objective The aim of this study was to assess bone gain and stability following reconstruction with titanium mesh in the anterior region of the maxilla, irrespective of the biomaterial used for bone augmentation. Material and method Patient follow-up data were obtained from the Faculty's follow-up database. The focus was on individuals who had undergone rehabilitation in the anterior maxilla, previously augmented with bone grafts and growth factors in conjunction with titanium mesh. This retrospective cohort study involved at least 10 patients who met the inclusion criteria. Following an initial review of medical records, the eligible patients were invited for evaluation appointments. Result Out of 39 patients who had undergone guided bone regeneration surgery using titanium mesh, 12 met the inclusion criteria. As such, 17 sites suitable for the study were obtained, from which total of 276 tomographic measurements were then taken. There was a noticeable increase in thickness at all assessment levels relative to the bone crest apex, both immediately (T1) and six months post-surgery (T2), compared to baseline measurements (T0). Moreover, bone thickness tended to increase with the proximity to the apical level. Conclusion The use of titanium mesh combined with various biomaterials has yielded favorable outcomes in terms of augmenting bone volume.

Advances in biomaterial science have allowed for unprecedented insight into the ability of material cues to influence stem cell function. These material approaches better recapitulate the microenvironment, providing a more realistic ex vivo model of the cell niche. However, recent advances in our ability to measure and manipulate niche properties in vivo have led to novel mechanobiological studies in model organisms. Thus, in this review, we will discuss the importance of material cues within the cell niche, highlight the key mechanotransduction pathways involved, and conclude with recent evidence that material cues regulate tissue function in vivo.

The field of regenerative engineering relies primarily on the dual technical platforms of cell selection/conditioning and biomaterial fabrication to support directed cell differentiation. As the field has matured, an appreciation for the influence of biomaterials on cell behaviors has resulted in engineered matrices that meet biomechanical and biochemical demands of target pathologies. Yet, despite advances in methods to produce designer matrices, regenerative engineers remain unable to reliably orchestrate behaviors of therapeutic cells in situ. Here, we present a platform named MATRIX whereby cellular responses to biomaterials can be custom defined by combining engineered materials with cells expressing cognate synthetic biology control modules. Such privileged channels of material-to-cell communication can activate synthetic Notch receptors and govern activities as diverse as transcriptome engineering, inflammation attenuation, and pluripotent stem cell differentiation, all in response to materials decorated with otherwise bioinert ligands. Further, we show that engineered cellular behaviors are confined to programmed biomaterial surfaces, highlighting the potential to use this platform to spatially organize cellular responses to bulk, soluble factors. This integrated approach of co-engineering cells and biomaterials for orthogonal interactions opens new avenues for reproducible control of cell-based therapies and tissue replacements.

Electrically conductive biomaterials direct cell behavior by capitalizing on the effect of bioelectricity in tissue homeostasis and healing. Many studies have leveraged conductive biomaterials to influence cells and improve tissue healing, even in the absence of external stimulation. However, most studies using electroactive materials neglect characterizing how the inclusion of conductive additives affects the material's mechanical properties, and the interplay between substrate electrical and mechanical properties on cell behavior is poorly understood. Furthermore, mechanisms dictating how electrically conductive materials affect cell behavior in the absence of external stimulation are not explicit. In this study, we developed a mechanically and electrically tunable conductive hydrogel using agarose and the conductive polymer PEDOT:PSS. Under certain conditions, we observed that the hydrogel physical and electrical properties were decoupled. We then seeded human mesenchymal stromal cells (MSCs) onto the hydrogels and observed enhanced adhesion and spreading of MSCs on conductive substrates, regardless of the hydrogel mechanical properties, and despite the gels having no cell-binding sites. To explain this observation, we measured protein interaction with the gels and found that charged proteins adsorbed significantly more to conductive hydrogels. These data demonstrate that conductivity promotes cell adhesion, likely by facilitating increased adsorption of proteins associated with cell binding, providing a better understanding of the mechanism of action of electrically conductive materials.

Currently, scientists search for new materials for temporary implants that can dissolve in the body, which leads to the fact that there is no need for repeated surgery. In the last decade, scientific interest has focused on zinc-based materials because, unlike other metals, it has suitable corrosion rates and good biocompatibility. The paper describes an experiment for the study of the influence of deformation on the microstructure, strength and corrosion properties of an alloy of the Zn–Fe–Mg system. The authors carried out energy dispersive analysis and calculation of the volume fraction of the second phase of the Zn–Fe–Mg zinc alloy. The corrosion properties of the Zn–Fe–Mg zinc alloy with different microstructures (before and after high-pressure torsion) were studied using the gravimetric method under conditions simulating conditions inside a living organism (temperature, corrosive environment composition). During the tests, the corrosion mechanism was determined, its rate and mass loss of the samples were calculated. The relief of the corrosion surface was studied using scanning electron microscopy. It has been found that the destruction of the material in a corrosive environment occurs through a matrix containing the active Mg metal. The results of calculations of the corrosion rate for the original sample and samples subjected to high-pressure torsion differed due to a more even distribution of second phase particles during severe plastic deformation. In this work, by alloying zinc with iron and magnesium, as well as using high-pressure torsion, it was possible to increase the microhardness of the samples to 239.6±8 HV, which is a high indicator for zinc alloys.