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Imágenes sem y edx de muestras de HAp, hueso bovino y calcitita.
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The method by which to obtain Hydroxyapatite to be used as bone substitute should offer specific qualities such as, high purity, performance, low cost and has to be the following, bioactive, biocompatible, it has to have osteoconductivity and it has to bond directly to the bone. In this paper, synthetic HAp was prepared using 3 different methods re...
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Surface functionalization of highly bioresorbable biomaterials has been a challenging subject. The objective of our research is to establish a calcium phosphate (CaP) coating technique on a bioresorbable bone substitute material: hydroxyapatite and collagen nanocomposite for surface functionalization using supersaturated solutions. A coating techni...
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Bioactive, chemically bonded bone substitutes with antibacterial properties are highly recommended for medical applications. In this study, biomicroconcretes, composed of silicon modified (Si-αTCP) or non-modified α-tricalcium phosphate (αTCP), as well as hybrid hydroxyapatite/chitosan granules non-modified and modified with gold nanoparticles (AuN...
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Citations
... To date, our research group has carried out various studies in search of the ideal scaffold, evaluating grain size, purity, and crystallinity of synthetic and bovine HAps and of HAp obtained from the egg shell (HAp-egg shell), which share similar structures. Nevertheless, HAp-egg shell demonstrated additional advantages, such as being ecologically sustainable and readily available and having a low cost, properties which make it an ideal option [16][17][18]. HAp-egg shell/PLGA scaffolds have been also elaborated, reinforced with silicon, and osteoblastic cell viability on them was evaluated. The scaffolds obtained were highly porous and biocompatible, since they preserved cell morphology and 96% cell viability and adherence. ...
Background: Conventional periodontal therapy relies on bone regeneration strategies utilizing scaffolds made of diverse materials, among which collagen, to promote cell adhesion and growth. Objective: To evaluate periodontal ligament fibroblast (HPdLF) cell adhesion and viability for periodontal regeneration purposes on hydroxyapatite scaffolds containing collagen (HAp-egg shell)
combined with polylactic acid–polyglycolic acid copolymer (PLGA) and Platelet-Rich Fibrin (PRF). Methods: Four variations of the HAp-egg shell were used to seed HPdLF for 24 h and evaluate cell viability through a live/dead assay: (1) (HAp-egg shell/PLGA), (2) (HAp-egg shell/PLGA + collagen), (3) (HAp-egg shell/PLGA + PRF) and (4) (HAp-egg shell/PLGA + PRF + collagen). Cell adhesion and viability were determined using confocal microscopy and quantified using central tendency and dispersion measurements; significant differences were determined using ANOVA (p < 0.05). Results: Group 1 presented low cell viability and adhesion (3.70–10.17%); groups 2 and 3 presented high cell viability and low cell adhesion (group 2, 59.2–11.1%, group 3, 58–4.6%); group 4 presented the highest cell viability (82.8%) and moderate cell adhesion (45%) (p = 0.474). Conclusions: The effect of
collagen on the HAp-egg shell/PLGA scaffold combined with PRF favored HPdLF cell adhesion and viability and could clinically have a positive effect on bone defect resolution and the regeneration of
periodontal ligament tissue.
... Nevertheless, several studies have shown that HAp is preceded by several precursor phases, such as amorphous calcium phosphate (ACP), dicalcium phosphate dehydrated (DCPD), octacalcium phosphate (OCP), and calciumdeficient HAp (CDHA), which depends on the temperature, pH, and inhibitors that may be present in the environment [21][22][23]. The method to obtain HAp as a bone substitute should offer specific characteristics, such as high purity, performance, and low cost [21][22][23][24]. ...
... There are few reports studying the effect of magnetic fields on the deposition of Hap [23][24][25][26][27]. Most of the works deal with the effect of the magnetic field in the crystallization, orientation, and morphology of HAp crystals. ...
In this work, we evaluated the effect of a low magnetic field on the deposition of hydroxyapatite (HAp) on different metallic substrates. The substrates studied were titanium and BIOLINE stainless steel SS316LVM with and without Ta and TaN/Ta coatings. Before deposition, the uncoated Ti and SS316LVM substrates were treated with alkali to improve the adhesion of the films prompted to be formed. Next, all substrates (coated and uncoated) were immersed in stimulated body fluid (SBF) at physiological conditions of 37 °C, pH = 7.4, in the presence of magnetic fields from 0.15 T and 0.22 T for 7, 10, and 14 days. The formed films were characterized using SEM, FTIR, and the contact angle. Ti and SS316LVM substrates presented Ca/P relations closer to the stoichiometric HAp. It was demonstrated that in both coatings, Ta and Ta/N, an increase of the bioactivity was obtained. Additionally, our results showed that the application of magnetic fields has a significant effect on the increment in the mass:area ratio of HAp. Finally, the contact angle values were lower than 90°, showing an increase in hydrophilicity with respect to the metallic substrates.
... The statistical comparison showed that there were no significant differences between them. The calcium content in the samples evaluated is within the range of values reported by different authors for amorphous calcium phosphates synthesized by wet chemical method [7, 13,21,22]. ...
Hydroxyapatite, amorphous calcium phosphates, calcium triphosphate and calcium octaphosphate are the main components present in bones and teeth. Calcium phosphates are easily synthesized, playing an important role in regenerative medicine, being able to be used as bone implants. There are different ways of synthesizing phosphates, the most commonly used being wet chemical method. The objective of this work was to study the influence of the use of ultrasound and spray drying on the synthesis of amorphous calcium phosphate. Two synthetic variants were studied. One without ultrasound application and the other with ultrasound application. The samples obtained were characterized by X-ray diffraction, FTIR spectroscopy and scanning electron microscopy. The particle size by electron microscopy and the calcium content by atomic absorption was determined. The results showed that when spray drying is applied, particle sizes of less than 261 nm are obtained in the samples synthesized without ultrasound application, being less than 59 nm in the samples synthesized with ultrasound application. The statistical analysis by ANOVA showed significant differences between the particle sizes of the samples synthesized without ultrasound application and the samples synthesized by applying ultrasound. In both cases the particles were spherical. The results obtained show that the application of ultrasound during the synthesis process decreases the particle size, increasing the surface area, which favors the spray drying process.
The present study explores the effect of aging time on the properties of nano-hydroxyapatite (HAp) synthesized from chicken eggshells. CaO obtained from eggshells serves as calcium precursor which is combined with di-sodium hydrogen phosphate (Na2HPO4) as a phosphate precursor for the synthesis of HAp. The reaction precipitate is allowed to mature considering aging times of 12, 24, 36 and 48 h. The synthesized powders are characterized using FTIR and XRD to confirm the HAp formation. SEM micrographs of all the aged samples reveal dense agglomerated HAp particles. It is observed from the TEM results that the particle morphology of all the HAp samples appears to be nano-sized, spherical-shaped and polycrystalline in nature. A novel relationship between relative density vs. aging time is also established where relative density is found to increase with an increase in the aging time. In- vitro bioactivity and biodegradability evaluation of 12 h aged HAp with best physico-chemical properties show the formation of HCA apatite layer and significant weight loss respectively. In-vitro cytotoxicity test with Human Wharton’s Jelly Mesenchymal Stem Cells (hMSCs) (HiMedia CL001-T25) shows approximately 90 % cell viability assuring non-cytotoxicity of the 12 h aged HAp. The derived HAp can be a possible regenerative biomaterial for bone tissue engineering applications.
