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Hydroxyapatite has the closest chemical composition to human bone. Despite this, the use of nano-hydroxyapatite (nHA) to produce biocomposite scaffolds from a mixture of polylactic acid (PLA) and polycaprolactone (PCL) using cold isostatic pressing has not been studied intensively. In this study, biocomposites were created employing nHA as an osteoconductive filler and a polymeric blend of PLA and PCL as a polymer matrix for prospective usage in the medical field. Cold isostatic pressing and subsequent sintering were used to create composites with different nHA concentrations that ranged from 0 to 30 weight percent. Using physical and mechanical characterization techniques such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and density, porosity, tensile, and flexural standard tests, it was determined how the nHA concentrations affected the biocomposite's general properties. In this study, the presence of PLA, PCL, and nHA was well identified using FTIR, XRD, and SEM methods. The biocomposites with high nHA content showed intense bands for symmetric stretching and the asymmetric bending vibration of PO43−. The incorporation of nHA into the polymeric blend matrix resulted in a rather irregular structure and the crystallization became more difficult. The addition of nHA improved the density and tensile and flexural strength of the PLA/PCL matrix (0% nHA). However, with increasing nHA content, the PLA/PCL/nHA biocomposites became more porous. In addition, the density, flexural strength, and tensile strength of the PLA/PCL/nHA biocomposites decreased with increasing nHA concentration. The PLA/PCL/nHA biocomposites with 10% nHA had the highest mechanical properties with a density of 1.39 g/cm3, a porosity of 1.93%, a flexural strength of 55.35 MPa, and a tensile strength of 30.68 MPa. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) and polycaprolactone (PCL) are synthetic polymers that are extensively used in biomedical applications. However, the PLA/PCL blend produced by ball milling, followed by pressure compaction and sintering, has not been extensively explored. The goal of this research is to investigate the effect of the composition of biomaterials derived from PLA and PCL prepared by ball milling, followed by pressure compaction and sintering, on mechanical and physical properties. PCL and PLA with various concentrations were blended utilizing a ball milling machine for 2 h at an 80-rpm rotation speed. The obtained mixture was placed in a stainless steel 304 mold for the compacting process, which uses a pressure of 30 MPa to create a green body. The sintering procedure was carried out on the green body created at 150 °C for 2 h using a digital oven. The obtained PLA/PCL blend was tested using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), density, porosity, and three-point bending. Following the interaction between PCL and PLA in the PLA/PCL blend, the FTIR spectra and XRD diffractograms obtained in this work revealed a number of modifications in the functional groups and crystal phase. The 90PLA specimen had the best mechanical properties, with a maximum force and displacement of 51.13 N and 7.21 mm, respectively. The porosity of the PLA/PCL blend decreased with increasing PLA concentration so that the density and flexural properties of the PLA/PCL blend increased. The higher PCL content decreased the stiffness of the PLA molecular chain, consequently reducing its flexural properties. [ABSTRACT FROM AUTHOR]

Titanium and hydroxyapatite are widely used as materials for implants. Titanium has good mechanical properties, good corrosion resistance, and a high modulus of elasticity. Hydroxyapatite has good biocompatibility, bioactivity, and significant osteoinductivity. In this study, powder metallurgy was used as a method to combine titanium and hydroxyapatite for use in implants. Shellac was used as a binder between ceramic and metal due to its lower melting point. The surface morphology and chemical properties were evaluated by scanning electron microscopy–energy dispersive X-ray (SEM-EDX), whereby the SEM revealed the appearance of micropores in the Ti-HA composites during the sintering process, and the EDX showed that the final product had high amounts of Ti and Ca and low P. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) analyses were used to achieve the chemical characterization of composites, whereby a weak diffraction peak was observed in the XRD spectrum of Ti-HA composites, and the FTIR analysis confirmed that the composites had carbonate (CO3)2−, phosphate (PO4)3−, and hydroxyl (OH)− groups. Oxygen was sufficient due to the sintering process being conducted in an air environment. The antibacterial activities were characterized using the disc diffusion method with Escherichia coli and Staphylococcus aureus bacteria, whereby the prepared Ti-HA composites had a greater antibacterial effect on E. coli than on S. aureus. Finally, pH changes were observed during the 24 h incubation. The result showed that the Ti-HA composite did not contain chemical compounds that could cause harmful effects for humans and had good antibacterial activity against E. coli. [ABSTRACT FROM AUTHOR]

Application of metal bone screws for internal fixation has many risks, including infection, temperature sensitivity, and radiologic imaging disturbance. Bioabsorbable bone screws appear to overcome the disadvantages of metal bone screws. Many researchers have developed numerous bioabsorbable bone screws using various kinds of polymers. In this research, polylactic acid (PLA) and polyglycolic acid (PGA) were used as the materials for the bone screw. The injection molding method was used to produce the screws as it is one of the most effective methods in polymer or plastic production. This study aims to understand the effect of injection molding simulation parameters on shrinkage and warpage of bone screw, and to discover the best parameters combination to obtain optimal responses, and compare PLA and PGA bone screws. Injection molding simulation experiments used the Taguchi method, and the optimization process used particle swarm optimization. The results showed that melt temperature, injection time, and packing time had significant effects on shrinkage and warpage of PLA bone screws. Meanwhile, the significant factors for PGA bone screws were mold temperature, melt temperature, and injection time. After the optimization process, the shrinkage and warpage value improved to 2.4233% and 0.0928 mm for PLA bone screws and 8.9592% and 0.4646 mm for PGA bone screws. [ABSTRACT FROM AUTHOR]

This study aims to fabricate bio-composites of hydroxyapatite/shellac/sorghum as bone scaffold material in biomedical applications. Hydroxyapatite is made from bovine bone powder, while shellac is the end product from processing lice with adhesive properties, which are biodegradable and non-toxic. Furthermore, sorghum was used as a pore-forming material. The production of the materials was carried out using dry method which was sintered at a temperature of 1000°C. Subsequently, characterization of the bio-composites was carried out through X-Ray Diffraction, Scanning Electron Microscopy and Fourier Transform Infrared. The results of hardness and compression test were compared using pure hydroxyapatite and human bone as gold standard material. Furthermore, the biodegradation rate of these materials was also reported. [ABSTRACT FROM AUTHOR]

The aims of the study are to find out bio-printer extruder pressure effect toward the hardness and compressive strength of bovine hydroxyapatite (BHA). BHA and Glycerin are mixed with a 1:1 ratio. After 24 h bioink will be formed and can be used as a material to print scaffold. The scaffold is printed with a pressure variation of 100, 150, 200 and 250 KPa. After the printing process is done, the scaffold is kept on heat bed for 10 min with 100°C temperature. The hardness test result in this study has the highest value of 24.23 ± 1.22 HVN and 2.03 ± 0.12 HVN for its lowest. The compressive strength test has the highest value of 5.71 ± 0.42 MPa with the lowest value of 3.22 ± 0.13 MPa. The observation of BHA scaffold pores using a microscope shows that the pores have an average size of 100–200 µm. [ABSTRACT FROM AUTHOR]

This research aims to develop the model of land utilization in private forest management in order to support the food sustain in agroforestry system. The result shows that the clustering private forest for crops can predict the crops development area in private forest and management of agroforestry system performance in private forest. This model is related to knowledge management dan crops zoning. The private forest zoning can be classified into 2 main components : (i) planting area (ii) type of plants cultivated by the farmers. The forest management consists of horticulture plants stands, labor. It can be concluded that clustering model of agroforestry area utilization in supporting food sustain which is managed by laction question zoning principles can predict the domination of crops in private forest area. The crops which still become the mainstay of society, cassava value LQ 3.53 is still cultivated in 2015. In addition, for stands, mangga value 3.58 is still potential as an alternative choice in order to add income of society around the forest area in 2015. [ABSTRACT FROM AUTHOR]

Objective: This review focuses on the in vitro degradation of eggshell-based hydroxyapatite for analyzing the weight loss of hydroxyapatite when applied in the human body. Cytotoxicity tests were used to observe cell growth and morphological effects. A systematic review and meta-analysis were conducted to observe the weight loss and viable cells of hydroxyapatite when used for implants. Method: Based on the Population, Intervention, Comparison, and Outcome (PICO) strategy, the articles used for literature review were published in English on SCOPUS, PubMed, and Google Scholar from 1 January 2012 to 22 May 2021. Data regarding existing experiments in the literature articles the in vitro degradation and cytotoxicity testing of eggshell-based hydroxyapatite determined the biocompatibility of the materials. A meta-analysis was conducted to calculate the mean difference between the solutions and soaking times used for degradation and the stem cells used for cytotoxicity. Results: From 231 relevant studies, 71 were chosen for full-text analysis, out of which 33 articles met the inclusion criteria for degradation and cytotoxicity analysis. A manual search of the field of study resulted in three additional articles. Thus, 36 articles were included in this systematic review. Significance: The aim of this study was to highlight the importance of the biocompatibility of eggshell-based hydroxyapatite. The weight loss and viability cells of eggshell-based hydroxyapatite showed optimum results for viable cells requirements above 70%, and there is a weight loss of eggshell-based hydroxyapatite for a material implant. The meta-analysis indicated significant differences in the weight loss of eggshell-based hydroxyapatite materials with different soaking times and solutions used. The various kinds of stem cells for incubation of cultured cells in contact with a device, either directly or through diffusions with various kinds of stem cells from animals and humans, yielded viability cells above 70%. [ABSTRACT FROM AUTHOR]