Search Results (262)

Innovation in oral implantology is constantly on the move, with a constant search for new biomaterials to overcome many of the limitations of the biomaterials used in current implantable medical devices. This study explores the biocompatibility of an innovative 5% calcium-to-zirconia (Ca-SZ) coating deposited by PVD on TA6V substrates for use in oral implantology. In order to determine the contribution of the Ca-SZ coating, an in vitro biocompatibility study was carried out to assess the potential influence of the Ca-SZ coating (1) on the viability and proliferation of saos-2 and HaCaT cells over a short-term exposure period of 96 h, (2) on the synthesis of pro-inflammatory cytokines, and (3) on the synthesis of osteogenic differentiation markers over a long-term exposure period of 21 days, in comparison with reference biomaterials. The sampling consisted of n = 3 biological replicates, and a p-value of <0.05 was used as the threshold for statistical significance. Viability and proliferation kinetics to WST-1 and CyQUANT NF, respectively, showed improved viability/proliferation of Ca-SZ exposed to both cell lines independently. The TNF-alpha and IL-6 assays revealed reduced levels of cytokines compared with the reference biomaterials, including the control groups. In parallel, in Saos-2 cells exposed to Ca-SZ for 21 days under osteogenic conditions increased expression of osteogenic markers, such as the synthesis of soluble collagens, alkaline phosphatase (ALP), osteopontin, and osteocalcin, reflecting dynamic and facilitated osteoblastic differentiation, which was supported by the formation of hydroxyapatite (HA) crystals observed by SEM micrograph and confirmed by EDS mapping. In conclusion, Ca-SZ demonstrates an overall better biocompatibility compared with reference biomaterials, linked to a bioactive interaction of calcium, promoting cell proliferation and differentiation for optimal osteointegration, underlining its potential as a relevant innovation for next-generation implants. Full article

The human bone is a dynamic, highly vascularized tissue composed of 60–70% minerals, which include mainly calcium phosphate (CaP) in the form of hydroxyapatite (HA) crystals, 30% organic matrix composed of type I collagen fibers, and less than 5% water and lipids. The crystals are formed inside the matrix vesicles (MVs) and are then released in the organic collagen-based fibrous matrix. Extracellular matrix (ECM) formation and mineralization processes, named osteogenesis, are associated with human mesenchymal stem cells (hMSCs) undergoing differentiation into osteoblasts (osteoblastogenesis). Osteogenesis is regulated by multiple intracellular signaling and genetic pathways and by environmental factors. Calcium flow is finely regulated and plays a key role in both osteoblastogenesis and osteogenesis. The formation and accumulation of CaP, the biogenesis of MVs, their secretion, and the deposition of HA crystals to fill the organic bone matrix are the fundamental events in the biomineralization process. In this paper, I will describe and discuss the recent findings and hypothesis on the molecular mechanism regulating this process. Full article

Saltwater crocodile (SC; Crocodylus porosus) bone, an underutilized by-product, can be converted into high-value bio-calcium (Biocal), serving as a potential source of calcium and minerals. This study aimed to produce SC bone Biocal as functional gel enhancer for fish bologna development and to increase calcium intake. The resulting bone powder was evaluated for physicochemical, microbiological, and molecular properties. Additionally, the textural, physicochemical, structural, and sensorial properties of the formulated fish bologna incorporating Biocal at varying levels (0–10% w/w) were also evaluated. Biocal, obtained as a fine white powder, had a 16.83% yield. Mineral analysis showed 26.25% calcium and 13.72% phosphorus, with no harmful metals or pathogens detected. X-ray diffraction confirmed hydroxyapatite with 69.92% crystallinity, while calcium bioavailability was measured at 22.30%. Amino acid analysis indicated high levels of glycine, proline, and hydroxyproline, essential for collagen support. The findings confirmed that SC bone Biocal is beneficial and safe for food fortification. Incorporating SC Biocal (2–10% w/w) significantly affected the fish bologna characteristics (p < 0.05). As the Biocal level increased, the gel strength, hardness, and shear force also increased. The addition of 6% (w/w) Biocal significantly improved the textural property, without a detrimental effect on the sensory attributes of the bologna gel (p < 0.05). SDS-PAGE analysis showed TGase-enhanced myosin heavy chain (MHC) cross-linking, particularly in combination with Biocal. Moreover, the enriched Biocal–bologna gel exhibited a finer and denser microstructure. Thus, SC Biocal, particularly at 6% (w/w), can serve as a functional gel enhancer in surimi-based products, without compromising organoleptic quality. Full article

Natural biomaterials have gained significant attention in modern dentistry due to their biocompatibility, biodegradability, and low immunogenicity. These materials, including alginate, cellulose, chitosan, collagen, and hydroxyapatite, have been widely explored for their applications in stomatology. They play a crucial role in periodontal disease treatment, caries prevention, and implantology, providing an alternative to synthetic materials. Natural polymers such as chitosan and cellulose are utilized in drug delivery systems and tissue regeneration, while hydroxyapatite serves as a bone substitute due to its osteoconductive properties. Collagen-based scaffolds and coatings enhance periodontal and bone tissue regeneration. Additionally, bioengineered and chemically modified biomaterials offer improved mechanical and biological characteristics, expanding their clinical applications. This review aims to provide a comprehensive analysis of the biological properties, advantages, and limitations of selected natural biomaterials in dentistry. It explores their applications in various aspects of stomatology, including periodontal disease prevention and regeneration, dental caries prevention, bone substitutes in implantology, and dental implant coating. Although natural biomaterials exhibit promising properties, further research is necessary to refine their performance, enhance stability, and ensure long-term safety. Advancements in nanotechnology and bioengineering continue to drive the development of innovative natural biomaterials, paving the way for more effective and biocompatible dental therapies. Full article

Bone diseases represent a growing healthcare challenge due to population aging and lifestyle changes. Although bone has a natural regenerative capacity, approximately 10% of fractures fail to heal properly, requiring advanced therapeutic approaches. Bone tissue engineering (BTE) has advanced the use of osteoinductive and osteoconductive biomaterials to support bone regeneration. Among them, Bio-Oss^® Collagen, a composite of bovine hydroxyapatite and collagen, has shown excellent biocompatibility and bioactivity properties. This study analyzes the effect of Bio-Oss^® Collagen on human bone marrow-derived mesenchymal stem cells (hBMSCs), assessing its osteoinductive and immunomodulatory potential. After 7 days of culture, the biomaterial modulated the expression of key genes involved in osteogenesis and chondrogenesis, which are known for their role in bone formation and maturation. At the same time, a downregulation of genes associated with bone resorption was observed. Secretome analysis revealed a controlled release of pro-regenerative cytokines, suggesting a role of the biomaterial in modulating inflammation to promote bone regeneration. Furthermore, immunofluorescence confirmed the high expression of osteocalcin and osteopontin, which are key markers of bone mineralization. These findings indicate that Bio-Oss^® Collagen supports osteogenesis and modulates the immune response, creating a microenvironment favorable for bone regeneration. Full article

The expansion of fisheries and aquaculture in recent decades has led to a substantial increase in fish by-products. This study investigates the extraction and characterization of calcium phosphates from the by-products of representative species in these industries, aiming to identify potential sources for biotechnological and pharmaceutical applications. Clean bones obtained by enzyme hydrolysis from the heads, central skeletons, and/or tails of Atlantic horse mackerel, blue whiting, hake, mackerel, and farmed turbot were subjected to calcination to obtain calcium phosphates. The clean bone content in terms of nitrogen, lipids, organic matter, total protein, and amino acids was evaluated together with the chemical bonds, structures, and elemental composition of calcium phosphates. Results indicated a significantly higher yield of wet bone recovery (23%, p < 0.05) for the central skeleton of Atlantic horse mackerel and the highest mineral fraction for the heads of Atlantic horse mackerel (73.2%), followed by that of blue whiting (72.6%). Hake and turbot presented the lowest mineral fractions and, therefore, the highest protein content (27–31%, p < 0.05), with significant levels of collagen-related amino acids (p < 0.05). X-ray diffraction (XRD) and Fourier-transform Raman spectroscopy (FT-Raman) confirmed the biphasic calcium phosphate composition for most samples based on hydroxyapatite with contributions of whitlockite/β-tricalcium phosphate. The highest contribution to the non-apatite phase was made by the central skeletons of both mackerel and Atlantic horse mackerel. Full article

Bone tissue engineering aims to restore lost bone and create an environment conducive to new bone formation. To address this challenge, we developed a novel biomimetic hydrogel that combines maleic anhydride–modified type I collagen (ColME) with maleic anhydride–modified demineralized and decellularized porcine bone matrix particles (mDBMp), forming a composite ColME–mDBMp (CMB) hydrogel. Chemical modification of collagen resulted in a high degree of substitution, thereby enhancing its photocrosslinkability. Integration of mDBMp into the ColME hydrogel via photocrosslinking resulted in enhanced physiological stability, reduced shrinkage, and improved mechanical strength compared to gelatin methacrylate (GelMA)-based hydrogels. Moreover, mineralization of the CMB hydrogel promoted the formation of pure hydroxyapatite (HAp) crystals, providing superior stiffness while maintaining ductility relative to GelMA-based hydrogels. In vitro, human bone marrow mesenchymal stem cells (hBMSCs) encapsulated in CMB hydrogels exhibited enhanced proliferation, cell–matrix interactions, and osteogenic differentiation, as evidenced by increased calcium deposition and histological analysis. These results demonstrate that the CMB hydrogel, enriched with extracellular matrix (ECM) components, shows considerable promise over current GelMA-based hydrogels for bone tissue engineering. Full article

The high biocompatibility and the key role of collagen in bone extracellular matrix make it useful for tissue engineering. However, the high demand, costs, and challenges of extracting good-quality collagen have led to the use of collagen derivatives and search for non-human alternatives. This study investigates fish and bovine collagen peptides (Coll_f and Coll_b, respectively) as sustainable sources for 3D-printed bone scaffolds by developing and characterizing peptide-incorporated alginate/hydroxyapatite-based bioinks. The chemical analysis revealed structural similarities between the peptides, while rheological tests showed a slightly higher viscosity of Coll_f-based inks, which improved shape fidelity during the printing process. Upon oscillating rheological tests, both the Coll_f and Coll_b-based ink formulations demonstrated a solid-like behavior at frequencies higher than 0.4 Hz, which is crucial for maintaining the printed structure integrity during extrusion. Although Coll_b-based inks exhibited better pore printability, Coll_f-based inks achieved superior resolution and geometry retention. Macro-porous structures printed from both inks showed good accuracy, with minimal shrinkage attributed to hydroxyapatite. Both the produced inks had a high gel fraction and swelling behavior, with Coll_b-based outperforming Coll_f-based inks. Finally, both ink formulations resulted to be cytocompatibile with human dermal fibroblasts. These findings position Coll_f- and Coll_b-based inks as promising alternatives for bone tissue scaffolds, offering a sustainable balance between performance and structural stability in 3D printing applications. Full article

Based on the potential of DPSCs as the most promising candidates for bone tissue engineering, we comprehensively investigated the time-dependent cellular and molecular changes that occur during their osteodifferentiation. To analyze this area in-depth, we used both cellular and molecular approaches. Morphological changes were monitored using bright-field microscopy, while the production of mineral deposits was quantified spectrophotometrically. The expression of a key mesenchymal stem cell marker, CD90, was assessed via flow cytometry. Finally, protein-level changes in whole cells were examined by fluorescence microscopy. Our results show successful long-term osteodifferentiation of the patient’s DPSCs within 25 days. In differentiated cells, mineralized extracellular matrix production gradually increased; in contrast, the expression of the specific stem cell marker CD90 significantly decreased. We observed dynamic changes in intracellular and extracellular proteins when collagen1 A1 and osteopontin appeared as earlier markers of osteogenesis, while apolipoprotein A2, bone morphogenetic protein 9, dentin sialophosphoprotein, and matrix metalloproteinase 8 were produced mainly in the late stages of this process. A decrease in actin microfilament expression indicated a reduction in cell proliferation, which could be used as another marker of osteogenic initiation. Our results suggest a coordinated process in vitro in which cells synthesize the necessary proteins and matrix components to regulate the growth of hydroxyapatite crystals and form the bone matrix. Full article

The lack of bone grafts represents a major issue in the orthopedic field, reconstructive surgery, and dentistry. There are several bone conditions that often demand the use of grafts, such as fractures, infections, and bone cancer. The number of bone cancer cases increased in the past few decades and along with it, the need for bone grafting materials. To avoid the use of autografts and allografts there has been an increased interest towards synthetic grafts. This research aims to develop some collagen/hydroxyapatite (Coll/HAp) scaffolds cross-linked with three different agents that could be used in bone tissue engineering (BTE). These scaffolds were obtained with a freeze-drying method after the in situ formation of hydroxyapatite inside the collagen matrix. They were structurally and morphologically characterized and evaluated in terms of antimicrobial activity on E. coli and S. aureus bacterial strains. The results revealed that the scaffolds have porous structures with interconnected pores of suitable dimensions and well-distributed inorganic phases. Coll/HAp samples showed great antibacterial activity even without the use of typically used antibacterial agents. These findings allow us to conclude that these scaffolds are promising candidates for use in BTE and bone cancer treatment after the incorporation of specific antitumoral drugs. Full article

The increasing prevalence of acute traumas, surgical wounds, and chronic skin wounds poses significant therapeutic challenges for wound treatment. One of the main concerns in wound care is the danger of infection, which is a significant barrier to healing and a cause of higher morbidity and mortality rates. The emergence of drug-resistant bacterial species is becoming more frequent every day. Antimicrobial dressings have become a viable strategy for wound healing and hospital expense savings. Several factors, such as the wound’s localization and state, microbial load, and cost, must be considered when choosing an appropriate antimicrobial dressing. One of the key goals of wound care is infection avoidance. This study addresses the therapeutic challenges of acute traumas, surgical wounds, and chronic skin wounds, focusing on infection prevention and combating drug-resistant bacterial strains. The research explores the development of novel composite wound dressings incorporating hydroxyapatite, known for its osteoconductive properties, and essential oils from basil and cinnamon, recognized for their antimicrobial activity. The study evaluates the impact of these additives on key properties such as surface morphology, water absorption, enzymatic degradation, and mechanical performance. Antimicrobial tests showed that two experimental samples (A1S and A1BS) exhibited significant activity against Escherichia coli but not on Staphylococcus aureus. The results highlight the dressings’ enhanced antimicrobial properties, mechanical strength, and controlled degradation, making them promising candidates for advanced wound healing. Tailored applications were identified, with each dressing composition offering unique benefits for specific wound-healing scenarios based on the balance between flexibility, structural support, and bioactivity. Full article

To overcome limitations of dentin bonding due to collagen degradation at a bonded interface, incorporating bioactive glass (BAG) into dentin adhesives has been proposed to enhance remineralization and improve bonding durability. This study evaluated sol–gel-derived BAGs (BAG79, BAG87, BAG91, and BAG79F) and conventional melt-quenched BAG (BAG45) incorporated into dentin adhesive to assess their remineralization and mechanical properties. The BAGs were characterized by using field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy for surface morphology. The surface area was measured by the Brunauer–Emmett–Teller method. X-ray diffraction (XRD) analysis was performed to determine the crystalline structure of the BAGs. Adhesive surface analysis was performed after approximating each experimental dentin adhesive and demineralized dentin by using FE-SEM. The elastic modulus of the treated dentin was measured after BAG-containing dentin adhesive application. The sol–gel-derived BAGs exhibited larger surface areas (by 400–600 times) than conventional BAG, with BAG87 displaying the largest surface area. XRD analysis indicated more pronounced and rapid formation of hydroxyapatite in the sol–gel BAGs. Dentin with BAG87-containing adhesive exhibited the highest elastic modulus. The incorporation of sol–gel-derived BAGs, especially BAG87, into dentin adhesives enhances the remineralization and mechanical properties of adhesive–dentin interfaces. Full article

Mild hypophosphatasia (HPP) can be difficult to distinguish from other bone disorders in the absence of typical symptoms such as the premature loss of primary teeth. Therefore, this study aimed to analyze the crystallinity of hydroxyapatite (HAp) and the three-dimensional structure of collagen in HPP teeth at the molecular level and to search for new biomarkers of HPP. Raman spectroscopy was used to investigate the molecular structure, composition, and mechanical properties of primary teeth from healthy individuals and patients with HPP. The results showed that the crystallinity of HAp decreased and the carbonate apatite content increased in the region near the dentin–enamel junction (DEJ) of HPP primary teeth. X-ray diffraction (XRD) analyses confirmed a decrease in HAp crystallinity near the DEJ, and micro-computed tomography (CT) scanning revealed a decrease in mineral density in this region. These results suggest incomplete calcification in HPP primary dentin and may contribute to the development of diagnostic and therapeutic agents. Full article

Background: The reparative regeneration of jawbone defects poses a significant challenge within the field of dentistry. Despite being the gold standard, autogenous bone materials are not without drawbacks, including a heightened risk of postoperative infections. Consequently, the development of innovative materials that can surpass the osteogenic capabilities of autologous bone has emerged as a pivotal area of research. Methods: Mesenchymal stem cells (MSCs), known for their multilineage differentiation potential, were isolated from human umbilical cords and transfected with miR-181a. The osteogenic differentiation of miR-181a/MSC was investigated. Then, physicochemical properties of miR-181a/MSC-loaded nano-hydroxyapatite (nHAC) scaffolds were characterized, and their efficacy and underlying mechanism in rat calvarial defect repair were explored. Results: miR-181a overexpression in MSCs significantly promoted osteogenic differentiation, as evidenced by increased alkaline phosphatase activity and expression of osteogenic markers. The miR-181a/MSC-loaded nHAC scaffolds exhibited favorable bioactivity and accelerated bone tissue repair and collagen secretion in vivo. Mechanistic studies reveal that miR-181a directly targeted the TP53/SLC7A11 pathway, inhibiting ferroptosis and enhancing the osteogenic capacity of MSCs. Conclusions: The study demonstrates that miR-181a/MSC-loaded nHAC scaffolds significantly enhance the repair of bone defects by promoting osteogenic differentiation and inhibiting ferroptosis. These findings provide novel insights into the molecular mechanisms regulating MSC osteogenesis and offer a promising therapeutic strategy for bone defect repair. 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