Search Results (1,973)

We present a novel method for preparing bioactive and biomineralized calcium phosphate (mCP)-loaded biopolymer composite scaffolds with a porous structure. Two types of polymers were investigated as matrices: one natural, cellulose acetate (CA), and one synthetic, polycaprolactone (PCL). Biomineralized calcium phosphate particles were synthesized via wet chemical precipitation, followed by the addition of organic biominerals, such as magnesium gluconate and zinc gluconate, to enhance the bioactivity of the pure CP phase. We compared the morphological and chemical characteristics of the two types of composites and assessed the effect of biomineralization on the particle structure of pure CP. The precipitated CP primarily consisted of nanocrystalline apatite, and the addition of organic trace elements significantly influenced the morphology by reducing particle size. FE-SEM elemental mapping confirmed the successful incorporation of mCP particles into both CA and PCL polymer matrices. Short-term immersion tests revealed that the decomposition rate of both composites is slow, with moderate and gradual ionic dissolution observed via ICP-OES measurements. The weight loss of the PCL-based composite during immersion was minimal, decreasing by only 0.5%, while the CA-based composite initially exhibited a slight weight increase before gradually decreasing over time. Full article

Mandibular bone defect reconstruction remains a significant challenge for surgeons worldwide. Among multiple biodegradable biopolymers, allogeneic bone scaffolds derived from human sources have been used as an alternative to autologous bone grafts, providing optimal conditions for cell recruitment, adhesion, and proliferation and demonstrating significant osteogenic properties. This study aims to investigate the bone microstructure of the human scapula as a source for allogeneic bone scaffold fabrication for mandibular tissue engineering purposes. We created color-coded anatomical maps of the scapula and the mandible, reflecting the best anatomical and geometrical match. In this pilot study, we hypothesized a microstructural similarity of these bone structures and evaluated the human scapula’s bone tissue engineering potential for mandibular bone tissue engineering by focusing on the microstructural characteristics. Lyophilized human scapular and mandibular bioimplants were manufactured and sterilized. Experimental bone samples from the scapula’s acromion, coracoid, and lateral border from the mandibular condyle, mandibular angle, and mental protuberance were harvested and analyzed using micro-CT and quantitative morphometric analysis. This pilot study demonstrates significant microstructural qualitative and quantitative intra-group differences in the scapular and mandibular experimental bone samples harvested from the various anatomical regions. The revealed microstructural similarity of the human scapular and mandibular bone samples, to a certain extent, supports the stated hypothesis and, thus, allows us to suggest the human scapula as an alternative off-the-shelf allogeneic scaffold for mandibular reconstruction and bone tissue engineering applications. Full article

With the development of 3D bioprinting and the creation of innovative biocompatible materials, several new approaches have brought advantages to patients and surgical teams. Increasingly more bone defects are now treated using 3D-bioprinted prostheses and implementing new solutions relies on the ability of engineers and medical teams to identify methods of anchoring 3D-printed prostheses and to reveal the potential influence of bioactive materials on surrounding tissues. In this paper, we described why limb salvage surgery based on 3D bioprinting is a reliable and effective alternative to amputations, and why this approach is considered the new standard in modern medicine. The preliminary results of 3D bioprinting in one of the most challenging fields in surgery are promising for the future of machine-based medicine, but also for the possibility of replacing various parts from the human body with bioactive-based constructs. In addition, besides the materials and constructs that are already tested and applied in the human body, we also reviewed bioactive materials undergoing in vitro or in vivo testing with great potential for human applications in the near future. Also, we explored the recent advancements in clinically available 3D-bioprinted constructs and their relevance in this field. Full article

Three-dimensional (3D) models with improved biomimicry are essential to reduce animal experimentation and drive innovation in tissue engineering. In this study, we investigate the use of alginate-based materials as polymeric inks for 3D bioprinting of osteogenic models using human bone marrow stem/stromal cells (hBMSCs). A composite bioink incorporating alginate, nano-hydroxyapatite (nHA), type I collagen (Col) and hBMSCs was developed and for extrusion-based printing. Rheological tests performed on crosslinked hydrogels confirm the formation of solid-like structures, consistently indicating a superior storage modulus in relation to the loss modulus. The swelling behavior analysis showed that the addition of Col and nHA into an alginate matrix can enhance the swelling rate of the resulting composite hydrogels, which maximizes cell proliferation within the structure. The LIVE/DEAD assay outcomes demonstrate that the inclusion of nHA and Col did not detrimentally affect the viability of hBMSCs over seven days post-printing. PrestoBlue^TM revealed a higher hBMSCs viability in the alginate-nHA-Col hydrogel compared to the remaining groups. Gene expression analysis revealed that alginate-nHA-col bioink favored a higher expression of osteogenic markers, including secreted phosphoprotein-1 (SPP1) and collagen type 1 alpha 2 chain (COL1A2) in hBMSCs after 14 days, indicating the pro-osteogenic differentiation potential of the hydrogel. This study demonstrates that the incorporation of nHA and Col into alginate enhances osteogenic potential and therefore provides a bioprinted model to systematically study osteogenesis and the early stages of tissue maturation in vitro. Full article

In recent years, the demand for orthopedic implants has surged due to increased life expectancy, necessitating the need for materials that better mimic the biomechanical properties of human bone. Traditional metal implants, despite their mechanical superiority and biocompatibility, often face challenges such as mismatched elastic modulus and ion release, leading to complications and implant failures. Polyetheretherketone (PEEK), a semi-crystalline polymer with an aromatic backbone, presents a promising alternative due to its adjustable elastic modulus and compatibility with bone tissue. This study explores the functionalization of sandblasted 3D-printed PEEK disks with the bioactive peptides Aoa-GBMP1α and Aoa-EAK to enhance human osteoblast response. Aoa-GBMP1α reproduces 48–69 trait of Bone Morphogenetic Protein 2 (BMP-2), whereas Aoa-EAK is a self-assembling peptide mimicking extracellular matrix (ECM) fibrous structure. Superficial characterization included X-ray photoelectron spectroscopy (XPS), white light interferometer analysis, static water contact angle (S-WCA), and force spectroscopy (AFM-FS). Biological assays demonstrated a significant increase in human osteoblast (HOB) proliferation, calcium deposition, and expression of osteogenic genes (RUNX2, SPP1, and VTN) on functionalized PEEK compared to non-functionalized controls. The findings suggest that dual peptide-functionalized PEEK holds significant potential for advancing orthopedic implant technology. Full article

Background/Objectives: The development of new materials incorporating bioactive molecules for tissue regeneration is a growing area of interest. The objective of this study was to develop a new complex specifically designed for bone and skin tissue engineering, combining chitosan, ascorbic acid-2-magnesium phosphate (ASAP), and β-tricalcium phosphate (β-TCP). Methods: Chitosan and the complexes chitosan/ASAP and chitosan/ASAP/β-TCP were prepared in membrane form, macerated to a particulate format, and then subjected to characterization through Fourier transform infrared (FTIR) spectroscopy, optical and scanning electron microscopy (SEM), zeta potential, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). Cell viability was evaluated through a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and with fluorescein diacetate (FDA) and propidium iodide (PI) staining in stem cells obtained from deciduous teeth. Statistical analyses were performed using analysis of variance (ANOVA), followed by Tukey’s test. Results: The FTIR results indicated the characteristic bands in the chitosan group and the complexation between chitosan, ASAP, and β-TCP. Microscopic characterization revealed a polydisperse distribution of micrometric particles. Zeta potential measurements demonstrated a reduction in surface charge upon the addition of ASAP and β-TCP to the chitosan matrix. TGA and DSC analyses further indicated complexation between the three components and the successful formation of a cross-linked structure in the chitosan matrix. Stem cells cultured with the particulate biomaterials demonstrated their biocompatibility. Statistical analysis revealed a significant increase in cell viability for the chitosan/ASAP and chitosan/ASAP/β-TCP groups compared to the chitosan control. Conclusions: Therefore, the chitosan/ASAP complex demonstrated potential for skin regeneration, while the chitosan/ASAP/β-TCP formulation showed promise as a biomaterial for bone regeneration due to the presence of β-tricalcium phosphate. Full article

Nanocomposites based on Fe₃O₄ and carbonaceous nanoparticles (CNPs), including carbon nanotubes (CNTs) and graphene derivatives (graphene oxide (GO) and reduced graphene oxide (RGO)), such as Fe₃O₄@GO, Fe₃O₄@RGO, and Fe₃O₄@CNT, have demonstrated considerable potential in a number of health applications, including tissue regeneration and innovative cancer treatments such as hyperthermia (HT). This is due to their ability to transport drugs and generate localized heat under the influence of an alternating magnetic field on Fe₃O₄. Despite the promising potential of CNTs and graphene derivatives as drug delivery systems, their use in biological applications is hindered by challenges related to dispersion in physiological media and particle agglomeration. Hence, a solid foundation has been established for the integration of various synthesis techniques for these nanocomposites, with the wet co-precipitation method being the most prevalent. Moreover, the dimensions and morphology of the composite nanoparticles are directly correlated with the value of magnetic saturation, thus influencing the efficiency of the composite in drug delivery and other significant biomedical applications. The current demand for this type of material is related to the loading of a larger quantity of drugs within the hybrid structure of the carrier, with the objective of releasing this amount into the tumor cells. A second demand refers to the biocompatibility of the drug carrier and its capacity to permeate cell membranes, as well as the processes occurring within the drug carriers. The main objective of this paper is to review the synthesis methods used to prepare hybrids based on Fe₃O₄ and CNPs, such as GO, RGO, and CNTs, and to examinate their role in the formation of hybrid nanoparticles and the correlation between their morphology, the dimensions, and optical/magnetic properties. Full article

Bone transplantation ranks second worldwide among tissue prosthesis surgeries. Currently, one of the most promising approaches is regenerative medicine, which involves tissue engineering based on polymer scaffolds with biodegradable properties. Once implanted, scaffolds interact directly with the surrounding tissues and in a fairly aggressive environment, which causes biodegradation of the scaffold material. The aim of this work is to experimentally investigate the changes in the effective mechanical properties of polylactide scaffolds manufactured using additive technologies. The mechanism and the rate of the degradation process depend on the chosen material, contact area, microstructural features, and overall architecture of sample. To assess the influence of each of these factors, solid samples with different dimensions and layers orientation as well as prototypes of functionally graded scaffolds were studied. The research methodology includes the assessment of changes in the mechanical properties of the samples, as well as their structural characteristics. Changes in the mechanical properties were measured in compression tests. Microcomputed tomography (micro-CT) studies were conducted to evaluate changes in the microstructure of scaffold prototypes. Changes caused by surface erosion and their impact on degradation were assessed using morphometric analysis. Nonlinear changes in mechanical properties were observed for both solid samples and lattice graded scaffold prototypes depending on the duration of immersion in NaCl solution and exposure to different temperatures. At the temperature of 37 °C, the decrease in the elastic modulus of solid specimens was no more than 16%, while for the lattice scaffolds, it was only 4%. For expedited degradation during a higher temperature of 45 °C, these ratios were 47% and 16%, respectively. The decrease in compressive strength was no more than 32% for solid specimens and 17% for scaffolds. The results of this study may be useful for the development of optimal scaffolds considering the impact of the degradation process on their structural integrity. Full article

Angiogenesis, the formation of new blood vessels, is a fundamental process in both physiological repair mechanisms and pathological conditions, including cancer and chronic inflammation. Hydrogels are commonly used as in vitro models to mimic the extracellular matrix (ECM) and support endothelial cell behavior during angiogenesis. Mesenchymal stem cells further augment cell and tissue growth and are therefore widely used in regenerative medicine. Here we examined the combination of distinct hydrogel types—fibrin, collagen, and human platelet lysate (HPL)—on the formation of capillaries in a co-culture system containing human umbilical vein endothelial cells (HUVECs) and bone marrow-derived mesenchymal stem cells (BM-MSCs). The mechanical properties and structural changes of the hydrogels were characterized through scanning electron microscopy (SEM) and nanoindentation over 10 days. Fibrin and HPL gels sustained complex network formations, with HPL gels promoting even vascular tube formation of up to 10-fold capillary caliber. Collagen gels supported negligible angiogenesis. Our results suggest that HPL gels in combination with MSC-EC co-culture may be employed to obtain robust vascularization in tissue engineering. This study provides a comparative analysis of fibrin, collagen, and HPL hydrogels, focusing on their ability to support angiogenesis under identical conditions. Our findings demonstrate the superior performance of HPL gels in promoting robust vascular structures, highlighting their potential as a versatile tool for in vitro angiogenesis modeling. Full article

During the past decade, there has been a continued increase in the demand for bone defect repair and replacement resulting from long-term illnesses or traumatic incidents. To address these challenges, tissue engineering research has focused on biomedical applications. This field concentrated on the development of suitable materials to enhance biological functionality and bone integration. Toward this aim, it is necessary to develop a proper material that provides good osseointegration and mechanical behavior by combining biopolymers with ceramics, which increase their mechanical stability and mineralization process. Hydroxyapatite (HAp) is synthesized from natural resources owing to its unique properties; for example, it can mimic the composition of bones and teeth of humans and animals. Biopolymers, including chitosan and alginate, combined with HAp, offer good chemical stability and strength required for tissue engineering. Composite biomaterials containing hydroxyapatite could be a potential substitute for artificial synthetic bone grafts. Utilizing various polymers and fabrication methodologies would efficiently customize physicochemical properties and suitable mechanical properties in synergy with biodegradation, thus enhancing their potential in bone regeneration. This review summarizes the commonly used polymers in tissue engineering, emphasizing their advantages and limitations. This paper also highlights recent advances in the production and investigation of HAp-based polymer composites used in biomedical applications. Full article

Background: This study describes a novel biomaterial consisting of a mixture of biphasic bioceramic obtained from waste generated by the sugar industry (Carbocal) and a medical-grade epoxy resin adhesive called LOCTITE^® M31 CLTM. The objective was to demonstrate the possibility of coating non-bioactive and non-biodegradable metallic surfaces on implantable elements. Methods: After preparation, the mixture was applied to the surfaces of hip prostheses composed of two distinct materials: polyetherimide and grade 5 titanium. In both cases, adhesion tests produced favourable results. Additionally, cell cultures were conducted using human foetal osteoblastic cell lines (hFOB 1.19). Results: It was observed that the mixture did not affect the proliferation of bone cells. Conclusions: This composite material was found to promote the growth of bone cells, suggesting its potential for fostering bone tissue development. Full article

Designing scaffolds similar to the structure of trabecular bone requires specialised algorithms. Existing scaffold designs for bone tissue engineering have repeated patterns that do not replicate the random stochastic porous structure of the internal architecture of bones. In this research, the Voronoi tessellation method is applied to create random porous biomimetic structures. A volume mesh created from the shape of a Zygoma fracture acts as a boundary for the generation of random seed points by point spacing to create Voronoi cells and Voronoi diagrams. The Voronoi lattices were obtained by adding strut thickness to the Voronoi diagrams. Gradient Voronoi scaffolds of pore sizes (19.8 µm to 923 µm) similar to the structure of the trabecular bone were designed. A Finite Element Method-based computational fluid dynamics (CFD) simulation was performed on all designed Voronoi scaffolds to predict the pressure drops and permeability of non-Newtonian blood flow behaviour using the power law material model. The predicted permeability (0.33 × 10⁻⁹ m² to 2.17 × 10⁻⁹ m²) values of the Voronoi scaffolds from the CFD simulation are comparable with the permeability of scaffolds and bone specimens from other research works. Full article

Background/Objectives: Cuminum cyminum L. has been utilized as a medicinal plant for centuries. This research sought to examine the effects of cumin methanolic extract (CMT) on the chondrogenic differentiation of human bone marrow-derived mesenchymal stem cells. Methods: Spheroids were generated using human stem cells and cultured with CMT at concentrations between 0 and 1 µg/mL. Morphological assessments and cell viability tests were conducted on days 1 and 3. Chondrogenic differentiation expression was evaluated through quantitative polymerase chain reaction, Western blot, and RNA sequencing. SOX9, FAM20B, COL2A1, and COL1A1 mRNA expression levels were determined using real-time polymerase chain reaction. Protein expression was analyzed via Western blot. Results: Throughout this study, the spheroids maintained their integrity and shape. No significant variations in spheroid diameter were observed among the groups. CMT treatment enhanced the expression of SOX9 and FAM20B. Conclusions: The methanolic extract of Cuminum cyminum facilitated chondrogenic differentiation in human bone marrow-derived mesenchymal stem cells by modulating SOX9 and FAM20B expression. This indicates its potential application in cartilage tissue engineering. Full article

A seven-month-old male Pomeranian presented with left forelimb lameness after a fall. Radiographic assessment confirmed proximal radial head and ulnar comminuted fracture. The initial surgical intervention involved the use of hybrid external skeletal fixation (ESF) to stabilize the radial head, concomitant with the application of a composite of bone morphogenetic protein type 2 (BMP-2)-loaded hydroxyapatite and gelatin microparticles at the fracture site. Although successful radial head healing was achieved, the ESF pinholes caused a defect in the proximal ulnar diaphysis. Subsequently, the ESF was removed, and a locking plate was applied in conjunction with the BMP-2-loaded collagen membrane to correct the radius defect. Clinical follow-up at 4.8 years postoperatively revealed a mildly decreased range of motion of the affected elbow joint, but no clinical symptoms such as lameness. Radiography revealed minimal degenerative changes and a radioulnar synostosis. Computed tomography revealed differences in the leg length and bone density. Gait analysis revealed that the left forelimb had a significant improvement in weight-bearing capacity based on weight distribution–peak vertical force metrics, compared with the right forelimb. Based on clinical outcomes, the combined application of hybrid ESF and bone tissue engineering techniques can be considered a feasible alternative treatment for radial head fractures. Full article

Cartilage degeneration is a key feature of aging and osteoarthritis, characterized by the progressive deterioration of joint function, pain, and limited mobility. Current treatments focus on symptom relief, not cartilage regeneration. Mesenchymal stromal cells (MSCs) offer a promising therapeutic option due to their capability to differentiate into chondrocytes, modulate inflammation, and promote tissue regeneration. This review explores the potential of MSCs for cartilage regeneration, examining their biological properties, action mechanisms, and applications in preclinical and clinical settings. MSCs derived from bone marrow, adipose tissue, and other sources can self-renew and differentiate into multiple cell types. In aging cartilage, they aid in tissue regeneration by secreting growth factors and cytokines that enhance repair and modulate immune responses. Recent preclinical studies show that MSCs can restore cartilage integrity, reduce inflammation, and improve joint function, although clinical translation remains challenging due to limitations such as cell viability, scalability, and regulatory concerns. Advancements in MSC delivery, including scaffold-based approaches and engineered exosomes, may improve therapeutic effectiveness. Potential risks, such as tumorigenicity and immune rejection, are also discussed, emphasizing the need for optimized treatment protocols and large-scale clinical trials to develop effective, minimally invasive therapies for cartilage regeneration. Full article