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Acta Biomaterialia Mar 2017The design of synthetic bone grafts to foster bone formation is a challenge in regenerative medicine. Understanding the interaction of bone substitutes with osteoclasts...
UNLABELLED
The design of synthetic bone grafts to foster bone formation is a challenge in regenerative medicine. Understanding the interaction of bone substitutes with osteoclasts is essential, since osteoclasts not only drive a timely resorption of the biomaterial, but also trigger osteoblast activity. In this study, the adhesion and differentiation of human blood-derived osteoclast precursors (OCP) on two different micro-nanostructured biomimetic hydroxyapatite materials consisting in coarse (HA-C) and fine HA (HA-F) crystals, in comparison with sintered stoichiometric HA (sin-HA, reference material), were investigated. Osteoclasts were induced to differentiate by RANKL-containing supernatant using cell/substrate direct and indirect contact systems, and calcium (Ca) and phosphorus (P) in culture medium were measured. We observed that OCP adhered to the experimental surfaces, and that osteoclast-like cells formed at a rate influenced by the micro- and nano-structure of HA, which also modulate extracellular Ca. Qualitative differences were found between OCP on biomimetic HA-C and HA-F and their counterparts on plastic and sin-HA. On HA-C and HA-F cells shared typical features of mature osteoclasts, i.e. podosomes, multinuclearity, tartrate acid phosphatase (TRAP)-positive staining, and TRAP5b-enzyme release. However, cells were less in number compared to those on plastic or on sin-HA, and they did not express some specific osteoclast markers. In conclusion, blood-derived OCP are able to attach to biomimetic and sintered HA substrates, but their subsequent fusion and resorptive activity are hampered by surface micro-nano-structure. Indirect cultures suggest that fusion of OCP is sensitive to topography and to extracellular calcium.
STATEMENT OF SIGNIFICANCE
The novelty of the paper is the differentiation of human blood-derived osteoclast precursors, instead of mouse-derived macrophages as used in most studies, directly on biomimetic micro-nano structured HA-based surfaces, as triggered by osteoblast-produced factors (RANKL/OPG), and influenced by chemistry and topography of the substrate(s). Biomimetic HA-surfaces, like those obtained in calcium phosphate cements, are very different from the conventional calcium phosphate ceramics, both in terms of topography and ion exchange. The role of these factors in modulating precursors' differentiation and activity is analysed. The system is closely reproducing the physiological process of attachment of host cells and further maturation to osteoclasts toward resorption of the substrate, which occurs in vivo after filling bone defects with the calcium phosphate grafts.
Topics: Biomimetic Materials; Bone Substitutes; Cell Adhesion; Cell Differentiation; Durapatite; Humans; Myeloid Progenitor Cells; Nanostructures; Osteoclasts; RANK Ligand
PubMed: 27940198
DOI: 10.1016/j.actbio.2016.12.013 -
Journal of Materials Science. Materials... Apr 2023It is imperative to investigate the effect of addition of different size metallic ions in HAp and study the changes in biocompatibility and mechanical properties. Silver...
It is imperative to investigate the effect of addition of different size metallic ions in HAp and study the changes in biocompatibility and mechanical properties. Silver and magnesium ions are two vital ions needed in our body. Silver ions are known to inhibit the microbes, while magnesium ions are known to increase the mechanical properties. The present study reports the comparative properties of MgHAp and AgHAp synthesised by sol-gel wet chemical method. Changes in the morphology, phase analysis, corrosion resistance, dielectric properties, hardness and the thrombus behaviour of HAp doped Ag and Mg ions has been investigated. In this work, we have presented a comparative study of both the metal doped ionsto find which of the ions and which weight percent of the ions can be best suited to be incorporated into the HAp matrix for hard tissue implants. All wt% AgHAp showed the better corrosion resistance than all the MgHAp samples. However, MgHAp showed higher value of hardness in comparison to AgHAp samples. The mechanical strength was found to increase with the increase in Mg wt% in MgHAp but for AgHAp the hardness value decreased with increase in the concentration. The impedance and dielectric loss decreased with increasing frequency for both the samples. Both the ion doped hydroxyapatite showed moderate clotting behaviour as compared to pure HAp. But 2 wt% MgHAp and 4 wt% AgHAp showed better thrombogenic behaviour. It is imperative to investigate the effect of addition of different size metallic ions in HAp and study the changes in biocompatibility and mechanical properties. Silver and magnesium ions are two vital ions needed in our body. Silver ions are known to inhibit the microbes, while magnesium ions are known to increase the mechanical properties. The present study reports the comparative properties of MgHAp and AgHAp synthesised by sol-gel wet chemical method. Changes in the morphology, phase analysis, corrosion resistance, dielectric properties, hardness and the thrombus behaviour of HAp doped Ag and Mg ions has been investigated. In this work we have presented a comparative study of both the metal doped ions to find which of the ions and which weight percent of the ions can be best suited to be incorporated into the HAp matrix for hard tissue implants. All wt% AgHAp showed the better corrosion resistance than all the MgHAp samples. However, MgHAp showed higher value of hardness in comparison to AgHAp samples. The mechanical strength was found to increase with the increase in Mg wt% in MgHAp but for AgHAp the hardness value decreased with increase in the concentration. The impedance and dielectric loss decreased with increasing frequency for both the samples. Both the ion doped hydroxyapatite showed moderate clotting behaviour as compared to pure HAp. But 2 wt% MgHAp and 4 wt% AgHAp showed better thrombogenic behaviour.
Topics: Coated Materials, Biocompatible; Durapatite; Ions; Magnesium; Silver; Prostheses and Implants
PubMed: 37117909
DOI: 10.1007/s10856-023-06725-3 -
PloS One 2023The total or partial loss of teeth in the Mexican population due to periodontal diseases and trauma causes the development of other conditions, such as limitations in...
The total or partial loss of teeth in the Mexican population due to periodontal diseases and trauma causes the development of other conditions, such as limitations in chewing and grinding food, pronunciation difficulties, and oral aesthetic alterations. In Mexico, oral diseases have been described to affect 87% of the population, according to reports by the health services, emphasizing that pregnant women and patients with diabetes mellitus have the highest risk of presenting with severe periodontal diseases or tooth loss, according to findings by the Mexican Health Department's Specific Action Program for the prevention, detection, and control of oral health problems (2013-2018). There was a 92.6% prevalence of dental caries in the population examined, and the prevalence of periodontal problems, mainly in 40-year-olds, was above 95%. The objective of this investigation was to manufacture and characterize porous 3D scaffolds with innovative chemical compositions, using phosphate-based bioactive glass, beta-phase tricalcium phosphate, and zirconium oxide, in variable quantities. The scaffold manufacturing method combined two techniques: powder metallurgy and polymer foaming. The results obtained in this research were promising since the mechanically tested scaffolds showed values of compressive strength and modulus of elasticity in the range of human trabecular bone. On the other hand, the in vitro evaluation of the samples immersed in artificial saliva at days 7 and 14 presented the calcium/phosphorus ratio = 1.6; this value is identical to the reported state-of-the-art figure, corresponding to the mineral phase of the bones and teeth. Likewise, the precipitation of the flower-like morphology was observed on the entire surface of the scaffold without zirconia; this morphology is characteristic of hydroxyapatite. On the other hand, the samples with 0.5 and 1.0 mol% zirconia showed less hydroxyapatite formation, with a direct correlation between scaffold dissolution and the amount of zirconia added.
Topics: Pregnancy; Humans; Female; Tissue Scaffolds; Porosity; Tooth Remineralization; Dental Caries; Calcium Phosphates; Durapatite; Glass
PubMed: 37200370
DOI: 10.1371/journal.pone.0284885 -
BioMed Research International 2019Hydroxyapatite/graphene oxide/platinum (HA/GO/Pt) nanocomposite was synthesized and electrodeposited on a pure zirconium substrate. The coated zirconium was annealed at...
Hydroxyapatite/graphene oxide/platinum (HA/GO/Pt) nanocomposite was synthesized and electrodeposited on a pure zirconium substrate. The coated zirconium was annealed at 200, 300, 400, and 600°C in vacuum furnace in presence of argon gas. The structure and morphology of the coated samples were characterized. Biocompatibility and wear and corrosion resistances of specimens were examined. The result of corrosion tests shows that the graphene into HA/Pt composites significantly improves their corrosion resistance. The wear tests results of uncoated and coated samples before and after annealing show that coated samples annealed at 300°C had better wear resistance compared with uncoated and coated samples at other temperatures. Furthermore, the biocompatibility test shows that the coatings improved the cell attachment and proliferation compared to the pure zirconium substrate.
Topics: Argon; Cell Proliferation; Coated Materials, Biocompatible; Durapatite; Graphite; Humans; Materials Testing; Nanocomposites; Osteoblasts; Platinum; Substrate Specificity; Surface Properties; Titanium; Zirconium
PubMed: 31321236
DOI: 10.1155/2019/4847932 -
Hua Xi Kou Qiang Yi Xue Za Zhi = Huaxi... Dec 2022The purpose of the study was to evaluate the effect of hydroxyapatite (HA)-based desensiti-zing agents and determine their influence on the bonding performance of mild... (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVES
The purpose of the study was to evaluate the effect of hydroxyapatite (HA)-based desensiti-zing agents and determine their influence on the bonding performance of mild universal adhesives.
METHODS
Mid-coronal dentin samples were sectioned from human third molars and prepared for a dentin-sensitive model. According to desensitizing applications, they were randomly divided into four groups for the following treatments: no desensitizing treatment (control), Biorepair toothpaste (HA-based desensitizing toothpaste) treatment, Dontodent toothpaste (HA-based desensitizing toothpaste) treatment, and HA paste treatment. Dentin tubular occlusion and occluded area ratios were evaluated by scanning electron microscopy (SEM). Furthermore, All-Bond Universal, Single Bond Universal, and Clearfil Universal Bond were applied to the desensitized dentin in self-etch mode. The wettability and surface free energy (SFE) of desensitized dentin were evaluated by contact angle measurements. Bonded specimens were sectioned into beams and tested for micro-tensile bond strength to analyze the effect of desensitizing treatment on the bond strength to dentin of universal adhesives.
RESULTS
SEM revealed that the dentin tubule was occluded by HA-based desensitizing agents, and the area ratios for the occluded dentin tubules were in the following order: HA group>Biorepair group>Dontodent group (<0.05). Contact angle analysis demonstrated that HA-based desensitizing agents had no statistically significant influence on the wettability of the universal adhesives (0.05). The SFE of dentin significantly increased after treatment by HA-based desensitizing agents (<0.05). The micro-tensile bond strength test showed that HA-based desensitizing toothpastes always decreased the μTBS values (<0.05), whereas the HA paste group presented similar bond strength to the control group (0.05), irrespective of universal adhesive types.
CONCLUSIONS
HA-based desensitizing agents can occlude the exposed dentinal tubules on sensitive dentin. When mild and ultra-mild universal adhesives were used for subsequent resin restoration, the bond strength was reduced by HA-based desensitizing toothpastes, whereas the pure HA paste had no adverse effect on bond strength.
Topics: Humans; Dental Cements; Dentin; Durapatite; Tensile Strength; Toothpastes
PubMed: 36416319
DOI: 10.7518/hxkq.2022.06.007 -
Acta Biomaterialia Sep 2016Benzoxaboroles are a family of molecules that are finding an increasing number of applications in the biomedical field, particularly as a "privileged scaffold" for the...
UNLABELLED
Benzoxaboroles are a family of molecules that are finding an increasing number of applications in the biomedical field, particularly as a "privileged scaffold" for the design of new drugs. Here, for the first time, we determine the interaction of these molecules with hydroxyapatites, in view of establishing (i) how benzoxaborole drugs may adsorb onto biological apatites, as this could impact on their bioavailability, and (ii) how apatite-based materials can be used for their formulation. Studies on the adsorption of the benzoxaborole motif (C7H7BO2, referred to as BBzx) on two different apatite phases were thus performed, using a ceramic hydroxyapatite (HAceram) and a nanocrystalline hydroxyapatite (HAnano), the latter having a structure and composition more similar to the one found in bone mineral. In both cases, the grafting kinetics and mechanism were studied, and demonstration of the surface attachment of the benzoxaborole under the form of a tetrahedral benzoxaborolate anion was established using (11)B solid state NMR (including (11)B-(31)P correlation experiments). Irrespective of the apatite used, the grafting density of the benzoxaborolates was found to be low, and more generally, these anions demonstrated a poor affinity for apatite surfaces, notably in comparison with other anions commonly found in biological media, such as carboxylates and (organo)phosphates. The study was then extended to the adsorption of a molecule with antimicrobial and antifungal properties (3-piperazine-bis(benzoxaborole)), showing, on a more general perspective, how hydroxyapatites can be used for the development of novel formulations of benzoxaborole drugs.
STATEMENT OF SIGNIFICANCE
Benzoxaboroles are an emerging family of molecules which have attracted much attention in the biomedical field, notably for the design of new drugs. However, the way in which these molecules, once introduced in the body, may interact with bone mineral is still unknown, and the possibility of associating benzoxaboroles to calcium phosphates for drug-formulation purposes has not been looked into. Here, we describe the first study of the adsorption of benzoxaboroles on hydroxyapatite, which is the main mineral phase present in bone. We describe the mode of grafting of benzoxaboroles on this material, and show that they only weakly bind to its surface, especially in comparison to other ionic species commonly found in physiological media, such as phosphates and carboxylates. This demonstrates that administered benzoxaborole drugs are unlikely to remain adsorbed on hydroxyapatite surfaces for long periods of time, which means that their biodistribution will not be affected by such phenomena. Moreover, this work shows that the formulation of benzoxaborole drugs by association to calcium phosphates like hydroxyapatite will lead to a rapid release of the molecules.
Topics: Adsorption; Bridged Bicyclo Compounds, Heterocyclic; Durapatite; Kinetics; Magnetic Resonance Spectroscopy; X-Ray Diffraction
PubMed: 27282646
DOI: 10.1016/j.actbio.2016.06.008 -
Scientific Reports Mar 2023Biomimicry is becoming deep-rooted as part of bioceramics owing to its numerous functional advantages. Naturally occurring hydroxyapatite (HA) apart from primary nano...
Biomimicry is becoming deep-rooted as part of bioceramics owing to its numerous functional advantages. Naturally occurring hydroxyapatite (HA) apart from primary nano structures are also characterised by various ionic substitutions. The ease of accommodating such key elements into the HA lattice is known to enhance bone healing properties of bioceramics. In this work, hydroxyapatite synthesized via biomimetic approach was substituted with individual as well as multiple cations for potential applications in bone repair. Ion substitutions of Sr, Mg and Zn was carried out on HA for the first time by using Serratia grown in a defined biomineralization medium. The individual ions of varying concentration substituted in Serratia HA (SHA) (Sr SHA, Mg SHA and Zn SHA) were analysed for crystallinity, functional groups, morphology and crystal size. All three showed decreased crystallinity, phase purity, large agglomerated aggregates and needle-shaped morphologies. Fourier transform infrared spectroscopy (FTIR) spectra indicated increased carbonate content of 5.8% resembling that of natural bone. Additionally, the reduced O-H intensities clearly portrayed disruption of HA lattice and subsequent ion-substitution. The novelty of this study lies primarily in investigating the co-substitution of a combination of 1% Sr, Zn and Mg in SHA and establishing the associated change in bone parameters. Scanning electron microscope (SEM) and transmission electron microscope (TEM) images clearly illustrated uniform nano-sized agglomerates of average dimensions of 20-50 nm length and 8-15 nm width for Sr SHA; 10-40 nm length and 8-10 nm width for both Zn SHA and Mg SHA and 40-70 nm length and 4-10 nm width in the case of 1% Sr, Zn, Mg SHA. In both individual as well as co-substitutions, significant peak shifts were not observed possibly due to the lower concentrations. However, cell volumes increased in both cases due to presence of Sr validating its dominant integration into the SHA lattice. Rich trace ion deposition was presented by energy dispersive X-ray spectroscopy (EDS) and quantified using inductively coupled plasma optical emission spectrometer (ICP-OES). In vitro cytotoxicity studies in three cell lines viz. NIH/3T3 fibroblast cells, MG-63 osteosarcoma cells and RAW 264.7 macrophages showed more than 90% cell viability proving the biocompatible nature of 1% Sr, Zn and Mg in SHA. Microbial biomineralization by Serratia produced nanocrystals of HA that mimicked "bone-like apatite" as evidenced by pure phase, carbonated groups, reduced crystallinity, nano agglomerates, variations in cell parameters, rich ion deposition and non-toxic nature. Therefore ion-substituted and co-substituted biomineralized nano SHA appears to be a suitable candidate for applications in biomedicine addressing bone injuries and aiding regeneration as a result of its characteristics close to that of the human bone.
Topics: Humans; Durapatite; Serratia marcescens; Biomimetics; Nanoparticles; Ions; Spectroscopy, Fourier Transform Infrared; X-Ray Diffraction
PubMed: 36934131
DOI: 10.1038/s41598-023-30996-z -
Journal of Biomedical Materials... Feb 2022Considerable attention has been given to the use of chitosan (CS)-based materials reinforced with inorganic bioactive signals such as hydroxyapatite (HA) to treat bone...
Considerable attention has been given to the use of chitosan (CS)-based materials reinforced with inorganic bioactive signals such as hydroxyapatite (HA) to treat bone defects and tissue loss. It is well known that CS/HA based materials possess minimal foreign body reactions, good biocompatibility, controlled biodegradability and antibacterial property. Herein, the bioactivity of these composite systems was analyzed on in vitro bone cell models for their applications in the field of bone tissue engineering (BTE). The combination of sol-gel approach and freeze-drying technology was used to obtain CS/HA scaffolds with three-dimensional (3D) porous structure suitable for cell in-growth. Specifically, our aim was to investigate the influence of bioactive composite scaffolds on cellular behavior in terms of osteoinductivity and anti-inflammatory effects for treating bone defects. The results obtained have demonstrated that by increasing inorganic component concentration, CS/HA (60 and 70% v/v) scaffolds induced a good biological response in terms of osteogenic differentiation of human mesenchymal stem cells (hMSC) towards osteoblast phenotype. Furthermore, the scaffolds with higher concentration of inorganic fillers are able to modulate the production of pro-inflammatory (TGF-β) and anti-inflammatory (IL-4, IL-10) cytokines. Our results highlight the possibility of achieving smart CS/HA based composites able to promote a great osteogenic differentiation of hMSC by increasing the amount of HA nanoparticles used as bioactive inorganic signal. Contemporarily, these materials allow avoiding the induction of a pro-inflammatory response in bone implant site.
Topics: Biocompatible Materials; Bone Regeneration; Chitosan; Durapatite; Nanocomposites; Osteogenesis; Tissue Engineering; Tissue Scaffolds
PubMed: 34331513
DOI: 10.1002/jbm.a.37283 -
Journal of the Mechanical Behavior of... Sep 2022The corrosion rate of Mg alloys is currently too high for viable resorbable implant applications. One possible solution is to coat the alloy with a hydroxyapatite (HA)...
The corrosion rate of Mg alloys is currently too high for viable resorbable implant applications. One possible solution is to coat the alloy with a hydroxyapatite (HA) layer to slow the corrosion and promote bone growth. As such coatings can be under severe stresses during implant insertion, we present a nano-mechanical and nano-tribological investigation of RF-sputtered HA films on AZ31 Mg alloy substrates. EDX and XRD analysis indicate that as-deposited coatings are amorphous and Ca-deficient whereas rapid thermal annealing results in c-axis orientation and near-stoichiometric composition. Analysis of the nanoindentation data using a thin film model shows that annealing increases the coating's intrinsic hardness (H) and strain at break (H/E) values, from 2.7 GPa to 9.4 GPa and from 0.043 to 0.079, respectively. In addition, despite being rougher, the annealed samples display better wear resistance; a sign that the rapid thermal annealing does not compromise their interfacial strength and that these systems have potential for resorbable bone implant applications.
Topics: Alloys; Coated Materials, Biocompatible; Corrosion; Durapatite; Magnesium; Materials Testing; Surface Properties
PubMed: 35717775
DOI: 10.1016/j.jmbbm.2022.105306 -
Chembiochem : a European Journal of... Jul 2021Extracellular matrix glycoproteins play a major role in bone mineralization and modulation of osteogenesis. Among these, the intrinsically disordered protein osteopontin...
Extracellular matrix glycoproteins play a major role in bone mineralization and modulation of osteogenesis. Among these, the intrinsically disordered protein osteopontin (OPN) is associated with the inhibition of formation, growth and proliferation of the bone mineral hydroxyapatite (HAP). Furthermore, post-translational modifications like phosphorylation can alter conformations and interaction properties of intrinsically disordered proteins (IDPs). Therefore, the actual interaction of OPN with a HAP surface on an atomic level and how this interaction is affected by phosphorylation is of great interest. Here, we study the interaction of full-length OPN on the surface of suspended HAP nanoparticles by solution NMR spectroscopy. We report the binding modes of this IDP and provide evidence for the influence of hyperphosphorylation on the binding character and an explanation for the differing roles in biomineralization. Our study moreover presents an easy and suitable option to measure interaction of nanoparticles in a stable suspension with full-length proteins.
Topics: Binding Sites; Durapatite; Magnetic Resonance Spectroscopy; Osteopontin; Solutions; Surface Properties
PubMed: 33914399
DOI: 10.1002/cbic.202100139