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Bone defects resulting from trauma or diseases that lead to bone loss have created a growing need for innovative materials suitable for treating bone-related conditions. The purpose of this study is, therefore, to synthesize and analyse the synergistic effects of cerium (Ce) and cerium–silver (Ce–Ag) doping of borosilicate bioactive glass (BBG) on the bioactivity, antibacterial properties, and biocompatibility for potential applications in bone tissue engineering. This study utilized a sol–gel Stöber method to synthesize doped BBGs based on S49B4. Characterization techniques were utilized to evaluate the thermal stability, elemental composition, structural integrity, and morphological properties of the synthesized Ce and AgCe-BBGs. Cytotoxicity was evaluated using a GMSM-K gingival cell line, while antimicrobial tests were conducted using clinical isolates of Escherichia coli and Staphylococcus aureus. The characterization results confirmed the successful incorporation of Ce and Ag, resulting in elongated pineal to spherical nanosized BG particles (33–68 nm). Thermal analysis indicated that silver exhibited lower thermal stability compared to cerium. Bioactivity tests indicated that while silver has intrinsic bioactive qualities, elevated cerium levels above 0.5 wt% may inhibit or delay apatite formation by generating insoluble cerium phosphate ions. Lactate dehydrogenase assays demonstrated that among other BBGs, SBAgCe1 showed the highest LDH activity, suggesting mild cytotoxicity. The co-doped BBG exhibited strong antibacterial activity through a complex interaction between Ag and Ce ionic exchange. Nonetheless, a careful balance of Ce and Ag concentrations is critical, as high levels can compromise bioactivity and increase cytotoxicity. The results highlight the potential of SBAgCe0.5 as a candidate for bone tissue engineering applications due to its favourable bioactivity, and antibacterial and cytocompatible properties, emphasizing the importance of optimizing dopant concentrations for therapeutic applications in favour of good health and the well-being of humanity. [ABSTRACT FROM AUTHOR]

The evolution of three dimensional (3D) printed porous metallic biomaterials and their clinical applications are currently receiving much consideration. Many research works have been focused on the shaping by 3D printing of lightweight metal implants with improved mechanical properties. In the same way, the effect of surface finishes on roughness and porosity distribution on biological properties is still debated. Therefore, several factors need to be addressed and revisited in this context. This review focuses on the importance of porous metallic implant design and its relationship with biological and mechanical properties. First, the additive manufacturing (AM) techniques for bio-inert metals and alloys will be discussed. The review will then introduce the most efficient surface treatments and coating approaches for biomedical porous metals to enhance bone tissue regeneration, prevent corrosion, reduce revision surgery and improve implant lifetime. A critical study of the various parameters impacting the biological properties will also be carried out in this review. [ABSTRACT FROM AUTHOR]

Autoclave curing is a manufacturing process for high-performance parts based on carbon fiber–reinforced polymers (CFRPs) used for large aircraft parts. Today, this manufacturing process is the reference in terms of quality and, therefore, the manufactured parts' mechanical performance and robustness. However, several parameters can impact the quality of the parts resulting from this process, which requires optimizing key manufacturing parameters. In this study, the effect of autoclave process parameters (i.e., temperature, pressure, and vacuum-pressure) on the glass transition temperature (Tg), laminate compressive modulus (LCM), laminate compressive strength (LCS), and interlaminar shear strength (ILSS) was investigated using three factors, three-level Box–Behnken design (BBD) and response surface methodology (RSM). In addition, the interactions of processing parameters with Tg, LCM, LCS, and ILSS were investigated, making this study an essential investigation for accurately selecting processing parameters. Thus, there is a functionally non-linear relationship between the interaction of the autoclave process parameters. Therefore, these parameters were optimized using RSM with the maximum Tg, LCM, LCS, and ILSS. The optimization and validation of the obtained models were carried out with an average relative error below 3% for all thermomechanical and mechanical properties, indicating that the BBD and optimization were correct. Because of this, the established regression models can accurately predict the Tg, LCM, LCS, and ILSS in autoclaved epoxy/carbon composite laminates. [ABSTRACT FROM AUTHOR]

Coating surfaces with bioactive glass can be defined as depositing fine bioactive glasses on biomaterial substrates. Cobalt-chromium is a viable alternative to stainless steel for long-term applications with superior ductility. The mechanical properties of cobalt-chromium alloys are high strength with elastic modulus of 220-2300 GPa, more significant than the 30 GPa of bones. Combining metals and bioactive glass results in high biocompatibility and improved bioactivity of implant surfaces. In addition, it triggers new bone tissue to regenerate through osteogenesis and mineralisation. However, implantation failure still occurs and requires surgery revision due to a lack of adequate bone bonding and delamination at the coating surface of the implant. The current review summarises the adhesion between bioactive glass coatings and cobalt-chromium substrates applied through electrophoretic deposition (EPD). [ABSTRACT FROM AUTHOR]

The improved bulk and surface function of manufactured implants has advanced implantation procedures, leading to a decline in surgical risks. Many current techniques discussed in the literature are related to additive manufacturing (AM) of lightweight implants based on reliable, precise, flexible scaffolds and capable of mimicking bone properties while incorporating other useful features. These techniques have evolved for the production of a variety of biocompatible materials. AM has progressed beyond prototype to full-scale manufacturing of metals, polymers and ceramic products. However, metallic implants often fail in vivo due to biocorrosion and deterioration, limiting implant longevity. This study reviews current trends and approaches to enhancing the surface corrosion resistance of porous metallic implants and the effect of interfacial films on biological activity. The art of porous metallic implants manufactured by AM and their biocorrosion behaviour are discussed. This review also evaluates future trends and perspectives in additively manufactured synthetic orthopaedic implants porous with enhanced surface morphology. [ABSTRACT FROM AUTHOR]

Process parameters for the autoclave cure method are critical to controlling manufacturing-induced microstructure and composite laminates' physical and mechanical properties. The effect of temperature, pressure, and vacuum on the degree of cure, density, fiber volume fraction, and void content of laminated composites was investigated by response surface methodology (RSM) and Box–Behnken Design (BBD), along with the application of analysis of variance (ANOVA), to examine the importance of regression models. The results showed that the degree of cure highly depends on the temperature. At the same time, for density, the linear effect of the pressure was the most significant term, followed by the interaction between the temperature and pressure, the quadratic terms of vacuum and pressure, and the linear terms of temperature and vacuum. All the linear terms, quadratic terms of pressure and vacuum, and interaction between temperature and pressure were significant for fiber volume fraction. However, void content has only five significant terms (the linear effect of the pressure followed by all the quadratic terms and the linear term of vacuum). The predicted responses using quadratic models were in good concordance with the experimental values (R 2 values were above 98% for all responses). [ABSTRACT FROM AUTHOR]