Healing of bone fractures highly depends on the biocompatibility, stability in biological conditions, biodegradability, technical functionality, and shelf‐life of biomaterials. Metallic biomaterials offer excellent mechanical properties and biocompatibility. However, metallic bone implants result in stress shielding, release of toxic ions, excessive wear, and corrosion. Polymer materials are being explored for bone implants due to their light‐weight, biocompatibility, biodegradability, and absence of stress shielding. In the new era, additive manufacturing (AM) is being preferred due to its capability of fabricating customer specific implants with minimum material wastage. However, AM based polymer implants lack in mechanical strength and biological properties. Surface modification of polymeric substrates using coatings and incorporation of bioadditives have been regarded as alternatives for improvement of mechanical and biological properties. This review discusses about various coating techniques and gives an overview about coatings and bioadditives that can be used for enhancement of properties. From the review, it is evident that reinforcement of hydroxyapatite to polylactic acid resulted in prevention of crack growth during shape recovery cycles which can be used for self‐fitting implants. Coatings have been successful in enhancing hydrophilicity, mechanical properties, anti‐biofouling, antibacterial and anti‐coagulative properties, adhesion, proliferation, and differentiation of cells on the coated surface. This review also discusses the challenges that need to be overcome for progression in this field.
Dopamine mainly consists of catechol and amine groups in high concentrations that are mainly responsible for interfacial adhesion of dopamine with the substrate and possesses the ability of oxidation through self‐polymerization that results in the formation of polydopamine. The weak mechanical properties of poly lactic acid (PLA) limit its applications in a variety of applications. Polydopamine is widely known for its deposition on a variety of organic and inorganic surfaces. The present study is aimed at studying the effect of the polydopamine coating on mechanical properties of PLA structures fabricated at varying infill density and coated at different concentrations of coating solution immersed for 4 and 7 h. The deposition of polydopamine coating on various PLA structures was confirmed with the help of scanning electron microscopy/energy dispersive spectroscopy analysis. Significant improvement in tensile and compression strengths was found, which was in agreement with the change in weight percentage analysis. The application of polydopamine coating led to improvement in hydrophilicity and degree of crystallinity with the increase in surface roughness of the polymer. The findings from this study will help in utilization of polydopamine‐coated PLA as an alternative over PLA with weak mechanical properties for biomedical applications involving high‐strength biomedical implants and bone tissue engineering.
Anthracyclines drugs are used as a treatment regime to combat cancer owing to their great chemotherapeutic potential. They are characterized by the presence of a wide range of derivatives, the most famous are doxorubicin and daunorubicin. The proposed action mechanism of anthracyclines and their derivatives to exert cytotoxic effect involves the intercalation of the drug molecule into nucleic acid and inhibition of the activity of topoisomerases. These events consequences in halting DNA replication and transcription mechanisms of the cell. Understanding of the structural and conformational changes associated with nucleic acid after binding with drugs provides significant knowledge for the development of more effective drugs. A comprehensive elucidation of the molecular mechanism(s) of action of anthracyclines drugs plays a significant role in the rational drug designing to obtain an effective, selective, and safe anti-cancer drugs.
Purpose The implications of metallic biomaterials involve stress shielding, bone osteoporosis, release of toxic ions, poor wear and corrosion resistance and patient discomfort due to the need of second operation. This study aims to use additive manufacturing (AM) process for fabrication of biodegradable orthopedic small locking bone plates to overcome complications related to metallic biomaterials. Design/methodology/approach Fused deposition modeling technique has been used for fabrication of bone plates. The effect of varying printing parameters such as infill density, layer height, wall thickness and print speed has been studied on tensile and flexural properties of bone plates using response surface methodology-based design of experiments. Findings The maximum tensile and flexural strengths are mainly dependent on printing parameters used during the fabrication of bone plates. Tensile and flexural strengths increase with increase in infill density and wall thickness and decrease with increase in layer height and wall thickness. Research limitations/implications The present work is focused on bone plates. In addition, different AM techniques can be used for fabrication of other biomedical implants. Originality/value Studies on application of AM techniques on distal ulna small locking bone plates have been hardly reported. This work involves optimization of printing parameters for development of distal ulna-based bone plate with high mechanical strength. Characterization of microscopic fractures has also been performed for understanding the fracture behavior of bone plates.
Distal fractures are the most commonly experienced type of fractures that require fixation of bone plates for healing of fractured bones. Poly Lactic Acid (PLA)‐based bone plates are porous and light in weight. However, they lack mechanical properties that limit their application in biomedical field. Polydopamine coating has been witnessed to undergo covalent interactions, enhancing the mechanical properties of the substrate. The present study is based on the fabrication of PLA‐based bone plates using Fused Filament Fabrication with varying infill patterns. The infill patterns in the study include octet, cubic, grid, concentric, lines, and gyroid. Thereafter, polydopamine coating was deposited on these bone plates using direct immersion coating method. In the study, the effect of infill pattern on coating deposition and modification of mechanical properties has been studied. The microscopic images of fractured bone plates were captured. It was concluded that polydopamine coating was successful in improving mechanical properties for all infill patterns. The findings suggested that a concentric pattern should be used for applications that require both high mechanical strength and maximum elongation at break because elongation at break is higher for concentric patterns than gyroid patterns. Also, for applications requiring only high mechanical strength, a gyroid pattern should be used.
Polylactic acid (PLA)‐based implants fabricated by 3D Printing process are biocompatible, porous in nature and light in weight. These biomimetic implants can be used as an alternative to metallic implants. However, such PLA‐based implants lack mechanical strength, limiting their application in biomedical field. In the present study, direct immersion coating technique has been used for application of polydopamine coating followed by studying the effect of input process parameters such as infill density, immersion time, speed of incubator shaker and concentration of coating solution using response surface methodology (RSM)‐based approach. Analysis of variance (ANOVA) has been applied for prediction of statistical models with respect to ultimate tensile and flexural strengths. The effect of individual process parameters has been discussed using main effect plots and the interactions occurring between significant parameters has been discussed using response surface and contour plots. From the findings, it was evident that infill density was highly significant parameter followed by immersion time, speed of incubator shaker and concentration of coating solution. Also, the mechanical properties improved with increase in infill density and immersion time. However, they initially increased and then decreased with increase in speed of incubator shaker and concentration of coating solution.
No abstract
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.