Proliferation Of Osteogenic Cells Research Articles

Advancements in biomedical coatings: A comprehensive review of DC magnetron sputtering on Ti–6Al–4V alloy

This study investigates the application of DC magnetron sputtering (MS) technology for producing TiN and ion-substituted Ca-P coatings on dental implant materials, demonstrating ultimate tensile strength (UTS) of 887 MPa, a modulus of elasticity of 11.3 × 106 MPa. The influence of various physical vapor deposition (PVD-MS) parameters—such as substrate temperature, post-heat treatment, deposition duration, discharge power, and bias voltage—on the characteristics of these coatings is examined. The research evaluates the advantages and limitations of PVD-MS in fabricating TiN and Ca-P coatings, with an emphasis on their impact on surface topography and chemical composition, which are critical factors influencing cellular behavior. The study reveals that while ion-substituted HA coatings can enhance cell adhesion, they may also exhibit cytotoxic effects, potentially limiting cell growth. It compares osteogenic cell proliferation rates between low-crystalline HA coatings and highly crystalline variants on Ti-based substrates, highlighting significant performance disparities. Additionally, PVD-MS demonstrates robust adhesion capabilities and facilitates the incorporation of therapeutic ions, effectively replicating bioapatite properties. The addition of coating on the substrate promotes additional strengthening mechanisms of the layers, leading to improved wear resistance compared to an alloyed substrate. Estimated values for hardness range between 7.2 and 8.4 GPa, and for Young's modulus, they range from 126 to 162 GPa. The study highlights the potential of PVD-MS in creating nanostructured Ca-P coatings on biodegradable metals, alloys, and polymeric biomaterials. This technology improves corrosion resistance, biocompatibility, chemical stability, wear resistance, and overall performance in various biomedical applications.

3D chitosan/hydroxyapatite scaffolds containing mesoporous SiO2-HA particles: A new step to healing bone defects

Biocompatible scaffolds with high mechanical strengths that contain biodegradable components could boost bone regeneration compared with nondegradable bone repair materials. In this study, porous chitosan (CS)/hydroxyapatite (HA) scaffolds containing mesoporous SiO2-HA particles were fabricated through the freeze-drying process. According to field emission scanning electron microscopy (FESEM) results, combining mesoporous SiO2-HA particles in CS/HA scaffolds led to a uniform porous structure. It decreased pore sizes from 320 ± 1.1 μm to 145 ± 1.4 μm. Moreover, the compressive strength value of this scaffold was 25 ± 1.2 MPa. The in-vitro approaches exhibited good sarcoma osteogenic cell line (SAOS-2) adhesion, spreading, and proliferation, indicating that the scaffolds provided a suitable environment for cell cultivation. Also, in-vivo analyses in implanted defect sites of rats proved that the CS/HA/mesoporous SiO2-HA scaffolds could promote bone regeneration via enhancing osteoconduction and meliorating the expression of osteogenesis gene to 19.31 (about 5-fold higher compared to the control group) by exposing them to the bone-like precursors. Further, this scaffold's new bone formation percentage was equal to 90 % after 21 days post-surgery. Therefore, incorporating mesoporous SiO2-HA particles into CS/HA scaffolds can suggest a new future tissue engineering and regeneration strategy.

Comparative evaluation of the effect of 2% graphene oxide and 5% hydroxyapatite nanoparticles in isolation and in combination on micro tensile bond strength of 5th generation adhesive

Background Graphene is the thinnest, strongest, and stiffest imaginable material. The biocompatible property of graphene oxide can initiate and facilitate cell adhesion, proliferation, and differentiation of periodontal ligament, osteogenic, and oral epithelial cells. Furthermore, the antibiofilm and anti-adhesion properties of graphene oxide in the prevention of dental biofilm infections, dental caries, and dental erosion as well as for implant surface modification and as an anti-quorum sensing agent. Composites are the most often utilized materials for restoration in the field of dentistry due to adhesive resins' improved mechanical and cosmetic properties. To safeguard the dentin and prevent dental cavities, dentin adhesives are utilized to affix hydrophobic resin composites to hydrophilic dentin tissue. Materials and Method Dental adhesives have a harder time adhering to dentin because it contains more water and is less mineralized than enamel. This makes the method more sensitive. Result As a result, it was chosen to assess and contrast the impact of 5% Hydroxyapatite nanoparticles and 2% Graphene oxide nanoparticles, both separately and together, on the Micro tensile bond strength of 5th generation adhesive. Conclusion Graphene oxide is the most versatile form of Graphite in structural and functional configuration. Graphene oxide possesses extraordinary physical, chemical, optical, electrical and mechanical properties. Among the graphene family nanomaterials, the reduced form of Graphite adding the oxygenated functional group to the structure increases the surface area and therefore exhibits enviable excellent interaction ability with metal and ions as well as organic species. Graphene oxide in dentistry has provided outstanding results in antimicrobial action, regenerative dentistry, bone tissue engineering, drug delivery, physicochemical properties, enhancement of dental biomaterials and oral cancer treatment.

The role of bone morphogenic protein 2 in composite scaffolds in tissue engineering: Narrative review

Background: Tissue engineering is currently used as an alternative treatment to accelerate bone tissue regeneration. Composite scaffolds play a role in osteoinduction and can enhance cell proliferation. The addition of bone morphogenetic protein-2 (BMP-2) to the scaffold can promote cell migration, cell proliferation, and the differentiation of genes related to osteogenesis. Methods: This paper employs a narrative review and searches through PubMed, Sage Journal, and Science Direct for studies published in the last 5 years, using keywords such as "Bone Morphogenetic Protein-2," "BMP-2," "Composite Scaffold," and "Tissue Engineering," resulting in the identification of 20 relevant journals. Discussion: The release of BMP-2 on composite scaffolds enhances osteogenic differentiation and cell proliferation to accelerate bone tissue regeneration. Osteogenic differentiation occurs through the activation of the WNT/β-catenin pathway by BMP-2, which then promotes the migration of endothelial cells and osteoblasts to the surrounding tissue, thereby speeding up bone formation. Conclusion: The application of BMP-2 on composite scaffolds can be used for tissue engineering.

RanGAP1 maintains chromosome stability in limb bud mesenchymal cells during bone development

BackgroundBone development involves the rapid proliferation and differentiation of osteogenic lineage cells, which makes accurate chromosomal segregation crucial for ensuring cell proliferation and maintaining chromosomal stability. However, the mechanism underlying the maintenance of chromosome stability during the rapid proliferation and differentiation of Prx1-expressing limb bud mesenchymal cells into osteoblastic precursor cells remains unexplored. MethodsA transgenic mouse model of RanGAP1 knockout of limb and head mesenchymal progenitor cells was constructed to explore the impact of RanGAP1 deletion on bone development by histomorphology and immunostaining. Subsequently, G-banding karyotyping analysis and immunofluorescence staining were used to examine the effects of RanGAP1 deficiency on chromosome instability. Finally, the effects of RanGAP1 deficiency on chromothripsis and bone development signaling pathways were elucidated by whole-genome sequencing, RNA-sequencing, and qPCR. ResultsThe ablation of RanGAP1 in limb and head mesenchymal progenitor cells expressing Prx1 in mice resulted in embryonic lethality, severe cartilage and bone dysplasia, and complete loss of cranial vault formation. Moreover, RanGAP1 loss inhibited chondrogenic or osteogenic differentiation of mesenchymal stem cells (MSCs). Most importantly, we found that RanGAP1 loss in limb bud mesenchymal cells triggered missegregation of chromosomes, resulting in chromothripsis of chromosomes 1q and 14q, further inhibiting the expression of key genes involved in multiple bone development signaling pathways such as WNT, Hedgehog, TGF-β/BMP, and PI3K/AKT in the chromothripsis regions, ultimately disrupting skeletal development. ConclusionsOur results establish RanGAP1 as a critical regulator of bone development, as it supports this process by preserving chromosome stability in Prx1-expressing limb bud mesenchymal cells.

A distinct "repair" role of regulatory T cells in fracture healing.

Regulatory T cells (Tregs) suppress immune responses and inflammation. Here, we described the distinct nonimmunological role of Tregs in fracture healing. The recruitment from the circulation pool, peripheral induction, and local expansion rapidly enriched Tregs in the injured bone. The Tregs in the injured bone displayed superiority in direct osteogenesis over Tregs from lymphoid organs. Punctual depletion of Tregs compromised the fracture healing process, which leads to increased bone nonunion. In addition, bone callus Tregs showed unique T-cell receptor repertoires. Amphiregulin was the most overexpressed protein in bone callus Tregs, and it can directly facilitate the proliferation and differentiation of osteogenic precursor cells by activation of phosphatidylinositol 3-kinase/protein kinase B signaling pathways. The results of loss- and gain-function studies further evidenced that amphiregulin can reverse the compromised healing caused by Treg dysfunction. Tregs also enriched in patient bone callus and amphiregulin can promote the osteogenesis of human pre-osteoblastic cells. Our findings indicate the distinct and nonredundant role of Tregs in fracture healing, which will provide a new therapeutic target and strategy in the clinical treatment of fractures.

Comparative evaluation of the effect of 2% graphene oxide and 5% hydroxyapatite nanoparticles in isolation and in combination on micro tensile bond strength of 5th generation adhesive

Background Graphene is the thinnest, strongest, and stiffest imaginable material. The biocompatible property of graphene oxide can initiate and facilitate cell adhesion, proliferation, and differentiation of periodontal ligament, osteogenic, and oral epithelial cells. Furthermore, the antibiofilm and anti-adhesion properties of graphene oxide in the prevention of dental biofilm infections, dental caries, and dental erosion as well as for implant surface modification and as an anti-quorum sensing agent. Composites are the most often utilized materials for restoration in the field of dentistry due to adhesive resins' improved mechanical and cosmetic properties. To safeguard the dentin and prevent dental cavities, dentin adhesives are utilized to affix hydrophobic resin composites to hydrophilic dentin tissue. Materials and Method Dental adhesives have a harder time adhering to dentin because it contains more water and is less mineralized than enamel. This makes the method more sensitive. Result As a result, it was chosen to assess and contrast the impact of 5% Hydroxyapatite nanoparticles and 2% Graphene oxide nanoparticles, both separately and together, on the Micro tensile bond strength of 5th generation adhesive. Conclusion Graphene oxide is the most versatile form of Graphite in structural and functional configuration. Graphene oxide possesses extraordinary physical, chemical, optical, electrical and mechanical properties. Among the graphene family nanomaterials, the reduced form of Graphite adding the oxygenated functional group to the structure increases the surface area and therefore exhibits enviable excellent interaction ability with metal and ions as well as organic species. Graphene oxide in dentistry has provided outstanding results in antimicrobial action, regenerative dentistry, bone tissue engineering, drug delivery, physicochemical properties, enhancement of dental biomaterials and oral cancer treatment.

Reuterin isolated from the probiotic Lactobacillus reuteri promotes periodontal tissue regeneration by inhibiting Cx43-mediated the intercellular transmission of endoplasmic reticulum stress.

The present study aimed to evaluate the effects of reuterin, a bioactive isolated from the probiotic Lactobacillus reuteri (L. reuteri) on periodontal tissue regeneration, and provide a new strategy for periodontitis treatment in the future. Data discussing the present state of the field: Probiotics are essential for maintaining oral microecological balance. Our previous study confirmed that probiotic L. reuteri extracts could rescue the function of mesenchymal stem cells (MSCs) and promote soft tissue wound healing by neutralizing inflammatory Porphyromonas gingivalis-LPS. Periodontitis is a chronic inflammatory disease caused by bacteria seriously leading to tooth loss. In this study, we isolated and purified reuterin from an extract of L. reuteri to characterize from the extracts of L. reuteri to characterize its role in promoting periodontal tissue regeneration and controlling inflammation in periodontitis. Chromatographic analysis was used to isolate and purify reuterin from an extract of L. reuteri, and HNMR was used to characterize its structure. The inflammatory cytokine TNFα was used to simulate the inflammatory environment. Periodontal ligament stem cells (PDLSCs) were treated with TNFα and reuterin after which their effects were characterized using scratch wound cell migration assays to determine the concentration of reuterin, an experimental periodontitis model in rats was used to investigate the function of reuterin in periodontal regeneration and inflammation control invivo. Real-time PCR, dye transfer experiments, image analysis, alkaline phosphatase activity, Alizarin red staining, cell proliferation, RNA-sequencing and Western Blot assays were used to detect the function of PDLSCs. In vivo, local injection of reuterin promoted periodontal tissue regeneration of experimental periodontitis in rats and reduced local inflammatory response. Moreover, we found that TNFα stimulation caused endoplasmic reticulum (ER) stress in PDLSCs, which resulted in decreased osteogenic differentiation. Treatment with reuterin inhibited the ER stress state of PDLSCs caused by the inflammatory environment and restored the osteogenic differentiation and cell proliferation functions of inflammatory PDLSCs. Mechanistically, we found that reuterin restored the functions of inflammatory PDLSCs by inhibiting the intercellular transmission of ER stress mediated by Cx43 in inflammatory PDLSCs and regulated osteogenic differentiation capacity. Our findings identified reuterin isolated from extracts of the probiotic L. reuteri, which improves tissue regeneration and controls inflammation, thus providing a new therapeutic method for treating periodontitis.

Preparation and properties of a 3D printed nHA/PLA bone tissue engineering scaffold loaded with a β-CD-CHX combined dECM hydrogel.

Jaw defects, which can result from a multitude of causes, significantly affect the physical well-being and psychological health of patients. The repair of these infected defects presents a formidable challenge in the clinical and research fields, owing to their intricate and diverse nature. This study aims to develop a personalized bone tissue engineering scaffold that synergistically offers antibacterial and osteogenic properties for treating infected maxillary defects. This study engineered a novel temperature-sensitive, sustained-release hydrogel by amalgamating β-cyclodextrin (β-CD) with chlorhexidine (CHX) and a decellularized extracellular matrix (dECM). This hydrogel was further integrated with a polylactic acid (PLA)-nano hydroxyapatite (nHA) scaffold, fabricated through 3D printing, to form a multifaceted composite scaffold (nHA/PLA/dECM/β-CD-CHX). Drug release assays revealed that this composite scaffold ensures prolonged and sustained release. Bacteriological studies confirmed that the β-CD-CHX loaded scaffold exhibits persistent antibacterial efficacy, thus effectively inhibiting bacterial growth. Moreover, the scaffold demonstrated robust mechanical strength. Cellular assays validated its superior biocompatibility, attributed to dECM and nHA components, significantly enhancing the proliferation, adhesion, and osteogenic differentiation of osteogenic precursor cells (MC3T3-E1). Consequently, the nHA/PLA/dECM/β-CD-CHX composite scaffold, synthesized via 3D printing technology, shows promise in inducing bone regeneration, preventing infection, and facilitating the repair of jaw defects, positioning itself as a potential breakthrough in bone tissue engineering.

Morphological aspects and distribution of granules composed of deproteinized bovine bone or human dentin into a putty mixture: an in vitro study

ObjectiveThe main aim of this study was to evaluate the morphological aspects and distribution of granules composed of deproteinized bovine bone mineral (DBBM) and human dentin-derived bone graft (HDBG) into a putty consistency mixture.Materials and methodsDBBM or HDBG were mixed with an alginate-based hydrogel at two different granule/hydrogel ratio (1:1 and 1:3) and divided into four test groups while two control groups were composed of DBBM or HDBG free of hydrogel. Groups of specimens were cross-sectioned for morphological evaluation by scanning electron microscopy (SEM) at backscattered electrons mode. Details on the dimensions and pores’ size of DBBM and HDBG were evaluated after mixing different amounts of particles and alginate-based hydrogels.ResultsMicroscopic analyses revealed a size of DBBM granules ranging from 750 up to 1600 μm while HDBG particles showed particle size ranging from 375 up to 1500 μm. No statistical differences were identified regarding the size of granules (p > 0.5). The mean values of pores’ size of DBBM particles were noticed at around 400 μm while HDBG particles revealed micro-scale pores of around 1–3 μm promoted by the dentin tubules (p < 0.05). The lowest distance between particles was at 125 μm for HDBG and 250 μm for DBBM when the particle content was increased. On decreasing the particles’ content, the distance between particles was larger for DBBM (~ 1000 μm) and HDBG (~ 1100 μm). In fact, statistically significant differences were found when the content of granules increased (p < 0.05).ConclusionsThe increased content of bioactive ceramic granules in a putty consistency mixture with hydrogel decreased the space among granules that can promote a high ceramic density and stimulate the bone growth over the healing process. Macro-scale pores on bovine bone mineral granules stimulate the formation of blood vessels and cell migration while the micro-scale pores of dentin-derived granules are proper for the adsorption of proteins and growth of osteogenic cells on the bone healing process.Clinical significanceA high amount of bioactive ceramic granules should be considered when mixing with hydrogels as a putty material since that result in small spaces among granules maintaining the bone volume over the bone healing process. Deproteinized bovine bone mineral granules have macro-scale pores providing an enhanced angiogenesis while dentin-derived granules possess only micro-scale pores for the adsorption of proteins and proliferation of osteogenic cells on the bone healing process. Further studies should evaluate the combination of different bioactive ceramic materials for enhanced bone healing.

Single-cell RNA landscape of osteoimmune microenvironment in osteoporotic vertebral compression fracture and Kümmell's disease.

Background: Single-cell RNA sequencing (scRNA-seq) enables specific analysis of cell populations at single-cell resolution; however, there is still a lack of single-cell-level studies to characterize the dynamic and complex interactions between osteoporotic vertebral compression fractures (OVCFs) and Kümmell's disease (KD) in the osteoimmune microenvironment. In this study, we used scRNA-seq analysis to investigate the osteoimmune microenvironment and cellular composition in OVCFs and KD. Methods: ScRNA-seq was used to perform analysis of fractured vertebral bone tissues from one OVCF and one KD patients, and a total of 8,741 single cells were captured for single-cell transcriptomic analysis. The cellularity of human vertebral bone tissue was further analyzed using uniform manifold approximation and projection. Pseudo-time analysis and gene enrichment analysis revealed the biological function of cell fate and its counterparts. CellphoneDB was used to identify the interactions between bone cells and immune cells in the osteoimmune microenvironment of human vertebral bone tissue and their potential functions. Results: A cellular profile of the osteoimmune microenvironment of human vertebral bone tissue was established, including mesenchymal stem cells (MSCs), pericytes, myofibroblasts, fibroblasts, chondrocytes, endothelial cells (ECs), granulocytes, monocytes, T cells, B cells, plasma cells, mast cells, and early erythrocytes. MSCs play an immunoregulatory function and mediate osteogenic differentiation and cell proliferation. The differentiation trajectory of osteoclasts in human vertebral bone tissue was also revealed. In addition, ECs actively participate in inflammatory infiltration and coupling with bone cells. T and B cells actively participate in regulating bone homeostasis. Finally, by identifying the interaction of ligand-receptor pairs, we found that immune cells and osteoclasts have bidirectional regulatory characteristics, have the effects of regulating bone resorption by osteoclasts and promoting bone formation, and are essential for bone homeostasis. It is also highlighted that CD8-TEM cells and osteoclasts might crosstalk via CD160-TNFRSF14 ligand-receptor interaction. Conclusion: Our analysis reveals a differential landscape of molecular pathways, population composition, and cell-cell interactions during OVCF development into KD. OVCFs exhibit a higher osteogenic differentiation capacity, owing to abundant immune cells. Conversely, KD results in greater bone resorption than bone formation due to depletion of MSCs and a relatively suppressed immune system, and this immune imbalance eventually leads to vertebral avascular necrosis. The site of action between immune cells and osteoclasts is expected to be a new therapeutic target, and these results may accelerate mechanistic and functional studies of osteoimmune cell types and specific gene action in vertebral avascular necrosis and pathological bone loss diseases, paving the way for drug discovery.

Octacalcium phosphate phase forming cements as an injectable bone substitute materials: Preparation and in vitro structural study

In the realm of regenerating damaged or degenerated bones through minimally invasive techniques, injectable materials have emerged as exceptionally promising. Among these, calcium phosphate bone cements (CPCs) have garnered significant interest due to their remarkable bioactivity, setting it apart from non-degradable alternatives such as polymethyl methacrylate cements. α-Tricalcium phosphate (α-TCP) is a widely used solid phase component in CPCs. It can transform into calcium-deficient hydroxyapatite (CDHAp) when it comes in contact with water. In this study, we aimed to create an injectable, self-setting bone cement using low-temperature synthesized α-TCP powder as a single precursor of the powder phase. We found that changes in the pH of the liquid phase (pH 6.0, pH 6.2, pH 7.0 and pH 7.4) significantly altered the cement's setting, handling, and mechanical properties. The formation of the octacalcium phosphate (OCP) phase was identified in our study, which positively affects the osteoblastic cell response. Hardened OCP-forming bone cements prepared using a liquid phase with pH 7.0 and 7.4 showed better osteogenic cell attachment and proliferation than those prepared with pH 6.0 and 6.2. Our study suggests that changes in the pH of the liquid phase can significantly affect the properties of α-TCP-based bone cement, and the presence of the OCP phase is crucial for optimal cement performance.

Comparative evaluation of the effect of 2% graphene oxide and 5% hydroxyapatite nanoparticles in isolation and in combination on micro tensile bond strength of 5th generation adhesive

Graphene is the thinnest, strongest, and stiffest imaginable material. The biocompatible property of graphene oxide can initiate and facilitate cell adhesion, proliferation, and differentiation of periodontal ligament, osteogenic, and oral epithelial cells. Furthermore, the antibiofilm and anti-adhesion properties of graphene oxide in the prevention of dental biofilm infections, dental caries, and dental erosion as well as for implant surface modification and as an anti-quorum sensing agent. Composites are the most often utilized materials for restoration in the field of dentistry due to adhesive resins' improved mechanical and cosmetic properties. To safeguard the dentin and prevent dental cavities, dentin adhesives are utilized to affix hydrophobic resin composites to hydrophilic dentin tissue. Dental adhesives have a harder time adhering to dentin because it contains more water and is less mineralized than enamel. This makes the method more sensitive. As a result, it was chosen to assess and contrast the impact of 5% Hydroxyapatite nanoparticles and 2% Graphene oxide nanoparticles, both separately and together, on the Micro tensile bond strength of 5th generation adhesive. Graphene oxide is the most versatile form of Graphite in structural and functional configuration. Graphene oxide possesses extraordinary physical, chemical, optical, electrical and mechanical properties. Among the graphene family nanomaterials, the reduced form of Graphite adding the oxygenated functional group to the structure increases the surface area and therefore exhibits enviable excellent interaction ability with metal and ions as well as organic species. Graphene oxide in dentistry has provided outstanding results in antimicrobial action, regenerative dentistry, bone tissue engineering, drug delivery, physicochemical properties, enhancement of dental biomaterials and oral cancer treatment.

Effect of Rotary Swaging on Mechanical and Operational Properties of Zn–1%Mg and Zn–1%Mg–0.1%Ca Alloys

A study of microstructure, phase composition, mechanical properties, corrosion processes, and biocompatibility in vitro of the Zn–1%Mg and Zn–1%Mg–0.1%Ca alloys in an annealed state and after rotary swaging (RS) is presented. Partially recrystallized microstructure is formed in the studied alloys after RS at 200 °C. RS reduces the mass fraction of intermetallic phases in comparison with annealed states of the alloys. RS at 200 °C increases the strength of the Zn–1%Mg and Zn–1%Mg–0.1%Ca alloys up to 248 ± 9 and 249 ± 9 with the growth of ductility up to 10.3 ± 3% and 14.2 ± 0.9%, respectively. The structure after RS at 200 °C does not lead to a change in the corrosion resistance of the studied alloys. However, an increase in the incubation period of the alloys in a growth medium slows down the degradation process due to the formation of a film consisting of degradation products. Rotary swaging does not impair the biocompatibility of the Zn–1%Mg and Zn–1%Mg alloys, maintaining the viability and integrity of blood cells, preventing hemolysis, and ensuring the adhesion and proliferation of osteogenic cells on the surface of samples.

Effect of different calcium-magnesium ratios on the properties of amorphous calcium pyrophosphate

In this paper, the property effect of different calcium-magnesium ratios on amorphous calcium pyrophosphate (ACPP) was studied. Three calcium-magnesium ratios (Ca-Mg = 1–2, Ca-Mg = 2, Mg = 0) was selected to prepare ACPP. To compare the changes in morphology, microstructure, phase and component, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive Spectroscopy (EDS), X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Brunauer–Emmett–Teller (BET) were carried out. Then, Inductively Coupled Plasma (ICP) was conducted to investigate the ion release. Finally, to compare the osteogenic activity, cell proliferation, adhesion, migration and osteogenic differentiation experiments were performed. The results showed that Mg2+ was inserted into the particle and adsorbed on the surface at Ca-Mg = 2. For Ca-Mg = 1–2, Mg2+ was mainly in a form of Mg-O-P. As a result, Ca-Mg = 2 had denser microstructure and better Ca2+ and Mg2+ release. Thus, Ca-Mg = 2 behaved superior osteogenic activity and differentiation ability.

Comparative evaluation of the effect of 2% graphene oxide and 5% hydroxyapatite nanoparticles in isolation and in combination on micro tensile bond strength of 5th generation adhesive

Graphene is the thinnest, strongest and stiffest imaginable material. The biocompatible property of graphene oxide can initiate and facilitate cell adhesion, proliferation and differentiation of periodontal ligament, osteogenic and oral epithelial cells. Furthermore, the antibiofilm and anti-adhesion properties of graphene oxide in prevention of dental biofilm infections, dental caries, dental erosion as well as for implant surface modification and as anti-quorum sensing agent. Composites are most often utilised materials for restoration in the field of dentistry due to adhesive resins' improved mechanical and cosmetic properties. To safeguard the dentin and prevent dental cavities, dentin adhesives are utilised to affix hydrophobic resin composites to hydrophilic dentin tissue. Dental adhesives have a harder time adhering to dentin because it contains more water and is less mineralized than enamel. This makes the method more sensitive. As a result, it was chosen to assess and contrast the impact of 5% Hydroxyapatite nanoparticles and 2% Graphene oxide nanoparticles, both separately and together, on the Micro tensile bond strength of 5th generation adhesive. Graphene oxide is the most versatile form of Graphite in structural and functional configuration. Graphene oxide possess extraordinary physical, chemical, optical, electrical and mechanical properties. Among the graphene family nanomaterials, the reduced form of Graphite adding the oxygenated functional group to the structure increases the surface area and therefore exhibits enviable excellent interaction ability with metal and ions as well as organic species. Graphene oxide in dentistry has provided outstanding results in antimicrobial action, regenerative dentistry, bone tissue engineering, drug delivery, physicochemical property, enhancement of dental biomaterials and oral cancer treatment.

Osteogenic cell proliferation and antibacterial properties of CaCu–NaTaO3 on biomedical tantalum

Tantalum (Ta) has been utilized used in hard tissue grafts because of its high mechanical strength, excellent corrosion resistance, and biocompatibility. However, due to its low bioactivity, inability to stimulate new bone formation, and lack of antimicrobial activity, its clinical application is limited. Ca2+ can efficiently enhance cell activity and stimulate cell differentiation to form new bone; Cu2+ is an antibacterial ion that is both biologically active and non-resistant at appropriate concentrations. A hydrothermal-molten salt-hydrothermal method was used in this study to create Ca2+ and Cu2+ co-doped NaTaO3. The findings demonstrate that the amount of Ca2+ and Cu2+ doped in the co-doped sample is significantly influenced by the doping sequence and the concentration of Cu2+ solution. The doping sequence of first doping Ca2+ and then doping Cu2+ can further increase the doping amount of the two ions. The change of doping sequence affects the surface morphology, interplanar spacing, and doping concentration. The optimum doping concentration of Ca2+ and Cu2+ in CaCu–NaTaO3 is 3.09 at.% and 2.31 at.%, and the film thickness is about 1.5 μm. ICP, cell, and antibacterial experiments proved that the CaCu–NaTaO3 film has biological and antibacterial activity.

Comparative evaluation of osteogenic cell growth on titanium surface and titanium coated with boron nitride surface: An in vitro study.

To promote better biological response and osseointegration continuous research is going on to modify the titanium (Ti) implant surface for successful implant treatment modality. This study aims to evaluate the osteogenic cell growth upon the uncoated Ti discs and boron nitride (BN) coated Ti to assess osseointegration and clinical success of dental implants. This is an descriptive experimental study which includes coating of uncoated titanium alloy suraface with boron nitride in the form of hexagonal boron nitride sheets. Than comparative evaluation of osteogenic cell growth upon both coated and uncoated titanium surfaces was done using specific cell growth determinants. In this descriptive experimental study, both BN-coated and uncoated Ti discs were assessed for osteogenic cell growth using 3-(4, 5-dimethyl thiazolyl-2)-2, 5-diphenyltetrazolium bromide assay, 4',6-diamidino-2-phenylindole, is a fluorescent stain assay, and cell adhesion assay. As this study is a descriptive experimental analysis between two variables only so there is no need of statistical analysis or p-value. Overall good cell adhesion, cell differentiation, and cell proliferation occurred in the BN-coated Ti discs as compared to uncoated Ti discs. To promote osseointegration of dental implants, surface coating with BN proved to be an effective approach toward better osseointegration and long-duration success of dental implants as a single unit or implant-supported prosthesis BN which is a biocompatible graphene material with advantages in chemical and thermal stability. BN promoted better osteogenic cell adhesion, differentiation, and proliferation. Hence, it can be used as a new promising Ti implant surface-coating material.

Enhanced mechanical performance and bioactivity in strontium/copper co-substituted diopside scaffolds

Effective scaffolds for bone-tissue-engineering are those that combine adequate mechanical and chemical performance with osseointegrative, angiogenetic and anti-bacterial modes of bioactivity. To address these requirements via a combined approach, we additively manufactured square strut scaffolds by robocasting precipitation-derived strontium/copper co-substituted diopside. Microstructure, mechanical performance, bioactivity, biocompatibility, and antibacterial activity were examined. The results show that the presence of strontium and copper in the diopside lattice reduces the grain size and increases the density of the ceramics. The compressive strength, hardness, and fracture toughness of the diopside showed improvement, attributed to a finer microstructure and improved sintering. Scaffolds had excellent compressive strength with a high porosity (68–72 %), which is attributed to the structure of the stacked-square-struts. All materials showed good in vitro bioactivity and favorable proliferation of osteogenic sarcoma cells, while strontium/copper co-doped materials exhibited the strongest anti-Escherichia coli activity. We show that across multiple indicators this system offers pathways towards high-performance bone substitutes.

Systematic comparation of the biological and transcriptomic landscapes of human amniotic mesenchymal stem cells under serum-containing and serum-free conditions

BackgroundHuman amniotic mesenchymal stem cells (hAMSCs) are splendid cell sources for clinical application in the administration of numerous refractory and relapse diseases. Despite the preferable prospect of serum-free (SF) condition for cell product standardization and pathogenic contamination remission, yet the systematic and detailed impact upon hAMSCs at both cellular and transcriptomic levels is largely obscure.MethodsFor the purpose, we preconditioned hAMSCs under serum-containing (SC) and SF medium for 48 h and compared the biological signatures and biofunctions from the view of cell morphology, immunophenotypes, multi-lineage differentiation in vitro, cell vitality, cytokine expression, and immunosuppressive effect upon the subpopulations of T lymphocytes, together with the PI3K-AKT-mTOR signaling reactivation upon cell vitality. Meanwhile, we took advantage of RNA-SEQ and bioinformatic analyses to verify the gene expression profiling and genetic variation spectrum in the indicated hAMSCs.ResultsCompared with those maintained in SC medium, hAMSCs pretreated in SF conditions manifested conservation in cell morphology, immunophenotypes, adipogenic differentiation, and immunosuppressive effect upon the proliferation and activation of most of the T cell subpopulations, but with evaluated cytokine expression (e.g., TGF-β1, IDO1, NOS2) and declined osteogenic differentiation and cell proliferation as well as proapoptotic and apoptotic cells. The declined proliferation in the SF group was efficiently rescued by PI3K-AKT-mTOR signaling reactivation. Notably, hAMSCs cultured in SF and SC conditions revealed similarities in gene expression profiling and variations in genetic mutation at the transcriptome level. Instead, based on the differentially expressed genes and variable shear event analyses, we found those genes were mainly involved in DNA synthesis-, protein metabolism-, and cell vitality-associated biological processes and signaling pathways (e.g., P53, KRAS, PI3K-Akt-mTOR).ConclusionsCollectively, our data revealed the multifaceted cellular and molecular properties of hAMSCs under SC and SF conditions, which suggested the feasibility of serum-free culture for the preferable preparation of standardized cell products for hAMSC drug development and clinical application.