Carbon Dot-Based Photo-Cross-Linked Gelatin Methacryloyl Hydrogel Enables Dental Pulp Regeneration: A Preliminary Study.

An essential factor in tooth nutritional deficits and aberrant root growth is pulp necrosis. Removing inflammatory or necrotic pulp tissue and replacing it with an inert material are the most widely used therapeutic concepts of endodontic treatment. However, pulp loss can lead to discoloration, increased fracture risk, and the reinfection of the damaged tooth. It is now anticipated that the pulp-dentin complex will regenerate through a variety of application methods based on human dental pulp stem cells (hDPSC). In order to create a photo-cross-linked gelatinized methacrylate hydrogel, GelMA/EUO-CDs-E (ECE), that is biodegradable and injectable for application, we created a novel nanoassembly of ECE based on eucommia carbon dots (EUO-CDs) and epigallocatechin gallate (EGCG). We then loaded it onto gelatin methacryloyl (GelMA) hydrogel. We have evaluated the material and examined its in vivo and in vitro angiogenesis-promoting potential as well as its dentin differentiation-enabling characteristics. The outcomes of the experiment demonstrated that GelMA/ECE was favorable to cell proliferation and enhanced hDPSC's capacity for angiogenesis and dentin differentiation. The regeneration of vascular-rich pulp-like tissues was found to occur in vivo when hDPSC-containing GelMA/ECE was injected into cleaned human root segments (RS) for subcutaneous implantation in nude mice. This suggests that the injectable bioscaffold is appropriate for clinical use in pulp regenerative medicine.

Exosome-based engineering strategies for the diagnosis and treatment of oral and maxillofacial diseases.

Oral and maxillofacial diseases are one of the most prevalent diseases in the world, which not only seriously affect the health of patients' oral and maxillofacial tissues, but also bring serious economic and psychological burdens to patients. Therefore, oral and maxillofacial diseases require effective treatment. Traditional treatments have limited effects. In recent years, nature exosomes have attracted increasing attention due to their ability to diagnose and treat diseases. However, the application of nature exosomes is limited due to low yield, high impurities, lack of targeting, and high cost. Engineered exosomes can be endowed with better comprehensive therapeutic properties by modifying exosomes of parent cells or directly modifying exosomes, and biomaterial loading exosomes. Compared with natural exosomes, these engineered exosomes can achieve more effective diagnosis and treatment of oral and maxillary system diseases, and provide reference and guidance for clinical application. This paper reviews the engineering modification methods of exosomes and the application of engineered exosomes in oral and maxillofacial diseases and looks forward to future research directions.

The Potential of Novel Synthesized Carbon Dots Derived Resveratrol Using One-Pot Green Method in Accelerating in vivo Wound Healing.

Background: Carbon dots (CDs), a novel nanomaterial, have gained significant attention over the past decade due to their remarkable fluorescence properties, low toxicity, and biocompatibility. These characteristics make them promising in various applications, especially in biomedicine. However, most CDs are currently synthesized using chemical materials, and their biocompatibility falls short of natural compounds. Research on extracting CDs from natural sources is limited, and their potential in biomedicine remains largely unexplored. Methods: We extracted CDs from resveratrol, a natural plant compound, and enhanced their water solubility using citric acid. Characterization of resveratrol-based carbon dots (RES-CDs) was carried out using various techniques, including UV-Vis, SEM, TEM, FTIR, XRD, and fluorescence spectroscopy. Extensive biocompatibility tests, wound healing assays, cell migration studies, and angiogenesis experiments were conducted using human umbilical vein endothelial cells (HUVEC). In addition, we investigated the biocompatibility and wound healing potential of RES-CDs in an in vivo rat model of inflammation. Results: RES-CDs exhibited stable yellow-green fluorescence under 365-nanometer ultraviolet light and demonstrated excellent biocompatibility. In wound healing experiments, RES-CDs outperformed resveratrol in terms of cell scratch healing, migration, and tube formation. In a rat skin defect model, RES-CDs promoted wound healing and stimulated the formation of blood vessels and tissue regeneration near the wound site, as evidenced by increased CD31 and VEGF expression. Conclusion: Resveratrol-derived CDs with enhanced water solubility show superior performance in tissue healing compared to resveratrol. This discovery opens new possibilities for the clinical application of resveratrol-based carbon dots.

Synthesis of multicolor luminescent carbon dots based on carboxymethyl chitosan for cell imaging and wound healing application: In vitro and in vivo studies.

The construction of biomaterials that can facilitate wound healing is significantly challenging in the medical field, and bacterial infections increase this complexity. In this study, we selected the biomacromolecule carboxymethyl chitosan as a carbon source and citric acid as an auxiliary carbon source. We prepared carbon quantum dots with multicolor luminescence properties and higher quantum yields (QYs) using a facile one-pot hydrothermal method. We characterized them to select carbon dots (CDs) suitable for cell growth. Subsequently, their biocompatibility with L929 cells, antibacterial properties against Staphylococcus aureus, and efficiency in promoting wound healing in vivo were investigated. Our experimental results showed that CDs at an appropriate concentration had excellent bioimaging ability, were suitable for cell growth, and accelerated the healing of infected wounds. We believe these bioactive CDs have great potential in promoting wound healing.

Applications of Bacterial Cellulose-Based Composite Materials in Hard Tissue Regenerative Medicine.

BACKGROUND: Cartilage, bone, and teeth, as the three primary hard tissues in the human body, have a significant application value in maintaining physical and mental health. Since the development of bacterial cellulose-based composite materials with excellent biomechanical strength and good biocompatibility, bacterial cellulose-based composites have been widely studied in hard tissue regenerative medicine. This paper provides an overview of the advantages of bacterial cellulose-based for hard tissue regeneration and reviews the recent progress in the preparation and research of bacterial cellulose-based composites in maxillofacial cartilage, dentistry, and bone. METHOD: A systematic review was performed by searching the PubMed and Web of Science databases using selected keywords and Medical Subject Headings search terms. RESULTS: Ideal hard tissue regenerative medicine materials should be biocompatible, biodegradable, non-toxic, easy to use, and not burdensome to the human body; In addition, they should have good plasticity and processability and can be prepared into materials of different shapes; In addition, it should have good biological activity, promoting cell proliferation and regeneration. Bacterial cellulose materials have corresponding advantages and disadvantages due to their inherent properties. However, after being combined with other materials (natural/ synthetic materials) to form composite materials, they basically meet the requirements of hard tissue regenerative medicine materials. We believe that it is worth being widely promoted in clinical applications in the future. CONCLUSION: Bacterial cellulose-based composites hold great promise for clinical applications in hard tissue engineering. However, there are still several challenges that need to be addressed. Further research is needed to incorporate multiple disciplines and advance biological tissue engineering techniques. By enhancing the adhesion of materials to osteoblasts, providing cell stress stimulation through materials, and introducing controlled release systems into matrix materials, the practical application of bacterial cellulose-based composites in clinical settings will become more feasible in the near future.

Biosafety evaluation of BaSi2O2N2:Eu2+/PDMS composite elastomers.

In recent years, mechanoluminescent (ML) materials have shown great potential in stress sensing, mechanical energy collection and conversion, so they have attracted wide attention in the field of stomatology. In the early stage of this study, BaSi2O2N2:Eu2+ ML phosphors were synthesized by two-step high temperature solid state method, and then mixed with Polydimethylsiloxane (PDMS) in different proportions to obtain BaSi2O2N2:Eu2+/PDMS ML composites with different mass fractions (10%,20%,30%,40%,50%). Then its biosafety was evaluated by Cell Counting Kit-8 (CCK-8), Calcein-AM/PI fluorescence staining, hemolysis, oral mucosal irritation, acute and subacute systemic toxicity tests. The experimental results show that the biosafety of BaSi2O2N2:Eu2+/PDMS ML composite elastomers with different mass fraction is in line with the existing standards, and other related properties can be further studied.