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Josep Anton Planell - One of the best experts on this subject based on the ideXlab platform.
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novel soybean gelatine based bioactive and injectable hydroxyapatite foam material properties and cell response
Acta Biomaterialia, 2011Co-Authors: Francesca Perut, Josep Anton Planell, Maria-pau Ginebra, Edgar B. Montufar, G Ciapetti, Matteo Santin, Jonathan P Salvage, Tania Traykova, Nicola BaldiniAbstract:Despite their known osteoconductivity, clinical use of calcium phosphate cements is limited both by their relatively slow rate of resorption and by rheological properties incompatible with Injectability. Bone in-growth and material resorption have been improved by the development of porous calcium phosphate cements. However, injectable formulations have so far only been obtained through the addition of relatively toxic surfactants. The present work describes the response of osteoblasts to a novel injectable foamed bone cement based on a composite formulation including the bioactive foaming agents soybean and gelatine. The foaming properties of both defatted soybean and gelatine gels were exploited to develop a self-hardening soy/gelatine/hydroxyapatite composite foam able to retain porosity upon injection. After setting, the foamed paste produced a calcium-deficient hydroxyapatite scaffold, showing good Injectability and cohesion as well as interconnected porosity after injection. The intrinsic bioactivity of soybean and gelatine was shown to favour osteoblast adhesion and growth. These findings suggest that injectable, porous and bioactive calcium phosphate cements can be produced for bone regeneration through minimally invasive surgery.
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calcium phosphate cements as bone drug delivery systems a review
Journal of Controlled Release, 2006Co-Authors: Maria-pau Ginebra, Tania Traykova, Josep Anton PlanellAbstract:Since calcium phosphate cements were proposed, several formulations have been developed, some of them commercialised, and they have proven to be very efficient bone substitutes in different applications. Some of their properties, such as the Injectability, or the low-temperature setting, which allows the incorporation of different drugs, make them very attractive candidates as drug carriers. In this article, the performance of calcium phosphate cements as carriers of different types of drugs, such as antibiotics, analgesics, anticancer, anti-inflammatory, as well as growth factors is reviewed.
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Injectability of a macroporous calcium phosphate cement
Key Engineering Materials, 2005Co-Authors: J A Delgado, Josep Anton Planell, I Harr, Amisel Almirall, Sergio Del Valle, Maria-pau GinebraAbstract:In this work an injectable and self setting calcium phosphate/albumen foam is developed. The effect of both the amount of albumen and the particle size of the starting a-tricalcium phosphate (a-TCP) powder on the Injectability of the cement paste is studied. X-ray diffraction (XRD) and infrared (IR) analysis of the samples reveal that the hydrolysis of a-TCP to calcium deficient hydroxyapatite (CDHA) is not affected by the addition of albumen. A foamed structure formed by spherical pores with diameters between 100 and 500 µm is observed by SEM. This porous structure is maintained after injection of the paste, although some deformation of the pores is produced due to the extrusion process. The Injectability of the cements is increased by the presence of albumen as compared with cements prepared in the same conditions but without foaming agent.
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Some factors controlling the Injectability of calcium phosphate bone cements
Journal of Materials Science: Materials in Medicine, 1998Co-Authors: Ibrahim Khairoun, M. G Boltong, F.c.m. Driessens, Josep Anton PlanellAbstract:The Injectability of four calcium phosphate bone cements (CPBCs) was measured using a commercial disposable syringe. It varied considerably with the cement powder composition, with the liquid/powder ratio, with the time after starting the mixing of liquid and powder, with the accelerator concentration (% Na2HPO4), and with the ageing time of the cement powder which was prepared by milling. The Injectability test could be used to determine accurately the dough time of CPBCs. Relations between the setting time and the cohesion time are discussed.
Marc Bohner - One of the best experts on this subject based on the ideXlab platform.
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evaluation of the ultrasonication process for Injectability of hydraulic calcium phosphate pastes
Acta Biomaterialia, 2012Co-Authors: Mohamed Habib, Gamal Baroud, Laetitia Galea, Marc BohnerAbstract:Abstract This study examined the use of ultrasonication to improve the Injectability of an aqueous calcium phosphate paste. Ultrasonication was applied to the paste through the plunger of the delivery syringe. A factorial design of experiments with three investigated factors, liquid to powder ratio (LPR) (38%, 39% and 40%), the size of the delivery syringe (5 and 10 ml) and the amplitude of the 20 kHz power ultrasonication (0–30 μm), was used in this study. The volume fraction of the extruded paste was used to quantify Injectability. Small Injectability improvements were observed with an increase in LPR and decrease in syringe size, which is consistent with previously published results. The improvements due to ultrasonication were significant and remarkable. For example, when using the 5 ml syringe the injected volume fraction of the 38% LPR paste improved from 63.4 ± 2.3% without ultrasonication to 97.3 ± 2.4% with 30%. This result shows that ultrasonication is an effective solution to improve Injectability.
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mechanisms underlying the limited Injectability of hydraulic calcium phosphate paste part ii particle separation study
Acta Biomaterialia, 2010Co-Authors: Mohamed Habib, Gamal Baroud, Francois Gitzhofer, Marc BohnerAbstract:Calcium phosphate cements (CPCs) are of great interest for bone augmentation procedures. In these a hydraulic calcium phosphate paste is injected through a small bore needle into the bone. The Injectability of these pastes is relatively poor, resulting into partial injection only. In earlier studies we have shown that phase separation brings the injection process to a halt. Phase separation is characterized by a faster flow of the liquid than of the solid during paste extrusion. So far it is unclear whether or not particle separation contributes to the poor Injectability of such hydraulic pastes. It is hypothesized that fine particles behave like a liquid and thus separate under the injection pressure, leaving larger particles behind. A factorial experimental design was used to examine this hypothesis. The particle size distribution (PSD) of the extrudate was measured over the course of each injection experiment using laser diffraction. The solid content of the paste was further inspected using scanning electron microscopy. A total of 48 experiments covering four factors at two levels each were performed. One factor was the ultrasound exposure duration, to ensure the dispersion quality of the particles during the PSD measurements. Another factor was the location of the samples over the course of the injection, so as to compare the extrudate with the PSDs remaining in the syringe. The liquid:powder ratio (LPR) in the injected paste was another factor investigated. Specifically, two different pastes with 40% and 50% LPR were examined. The dispersal medium was a fourth factor investigated, to ensure adequate dispersion of the particles during the PSD measurements. Analysis of variance showed that sample location did not significantly affect PSD. No apparent PSD change for the extruded paste and the paste remaining in the syringe could be detected by scanning electron microscopy. In conclusion, the present study did not show any evidence suggesting that particle separation occurred over the course of injection and thus that phase separation remains the main phenomenon leading to the poor Injectability of CPCs.
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mechanisms underlying the limited Injectability of hydraulic calcium phosphate paste
Acta Biomaterialia, 2008Co-Authors: Mohamed Habib, Gamal Baroud, Francois Gitzhofer, Marc BohnerAbstract:Calcium phosphate (CaP) cements are being increasingly used for minimally invasive hard tissue implantation. Possible approaches to improve the bad Injectability of hydraulic calcium phosphate pastes have been discussed and investigated in a number of recent publications. However, the liquid-phase separation mechanism leading to the limited Injectability has not yet been addressed. Liquid-phase separation means that the liquid-to-powder ratio (LPR) of the extruded paste is higher than the LPR of the paste left in the syringe. The goal of this paper was to remedy this situation by looking at the liquid-phase migration occurring during the injection of a paste from a syringe through a cannula. Experimentally, it was seen that the liquid content of both the syringe paste and the extrudate decreased during the paste injection. Moreover, a high extrusion velocity, small syringe size, short cannula and high LPR favored a good Injectability. These results could be partly explained in light of rheological measurements performed with the investigated paste.
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Injectability of calcium phosphate pastes
Biomaterials, 2005Co-Authors: Marc Bohner, Gamal BaroudAbstract:A theoretical model was developed to assess ways to improve the Injectability of calcium phosphate pastes. The theoretical results were then compared to experimental data obtained on calcium phosphate slips. The theoretical approach predicted that the Injectability of a cement paste could be improved by an increase of the liquid-to-powder ratio, and a decrease of the particle size and the plastic limit (PL) of the powder. The theoretical results were confirmed by experimental data. Interestingly, an increase of the viscosity of the mixing liquid with small additions of xanthan had a positive effect on the paste Injectability. This effect could be due to a change of the PL of the powder or to the lubricating effect of the polymer.
Maria-pau Ginebra - One of the best experts on this subject based on the ideXlab platform.
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critical review Injectability of calcium phosphate pastes and cements
Acta Biomaterialia, 2017Co-Authors: Rory Oneill, Maria-pau Ginebra, Edgar B. Montufar, Helen O Mccarthy, D I Wilson, Alex Lennon, Nicholas DunneAbstract:Abstract Calcium phosphate cements (CPC) have seen clinical success in many dental and orthopaedic applications in recent years. The properties of CPC essential for clinical success are reviewed in this article, which includes properties of the set cement (e.g. bioresorbability, biocompatibility, porosity and mechanical properties) and unset cement (e.g. setting time, cohesion, flow properties and ease of delivery to the surgical site). Emphasis is on the delivery of calcium phosphate (CaP) pastes and CPC, in particular the occurrence of separation of the liquid and solid components of the pastes and cements during injection; and established methods to reduce this phase separation. In addition a review of phase separation mechanisms observed during the extrusion of other biphasic paste systems and the theoretical models used to describe these mechanisms are discussed. Statement of Significance Occurrence of phase separation of calcium phosphate pastes and cements during injection limits their full exploitation as a bone substitute in minimally invasive surgical applications. Due to lack of theoretical understanding of the phase separation mechanism(s), optimisation of an injectable CPC that satisfies clinical requirements has proven difficult. However, phase separation of pastes during delivery has been the focus across several research fields. Therefore in addition to a review of methods to reduce phase separation of CPC and the associated constraints, a review of phase separation mechanisms observed during extrusion of other pastes and the theoretical models used to describe these mechanisms is presented. It is anticipated this review will benefit future attempts to develop injectable calcium phosphate based systems.
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Relevance of the setting reaction to the Injectability of tricalcium phosphate pastes
Acta biomaterialia, 2012Co-Authors: Edgar B. Montufar, Yassine Maazouz, Maria-pau GinebraAbstract:The aim of the present work was to analyze the influence of the setting reaction on the Injectability of tricalcium phosphate (TCP) pastes. Even if the injection was performed early after mixing powder and liquid, powder reactivity was shown to play a significant role in the Injectability of TCP pastes. Significant differences were observed between the injection behavior of non-hardening β-TCP pastes and that of self-hardening α-TCP pastes. The differences were more marked at low liquid-to-powder ratios, using fine powders and injecting through thin needles. α-TCP was, in general, less injectable than β-TCP and required higher injection loads. Moreover, clogging was identified as a mechanism hindering or even preventing Injectability, different and clearly distinguishable from the filter-pressing phenomenon. α-TCP pastes presented transient clogging episodes, which were not observed in β-TCP pastes with equivalent particle size distribution. Different parameters affecting powder reactivity were also shown to affect paste Injectability. Thus, whereas powder calcination resulted in an increased Injectability due to lower particle reactivity, the addition of setting accelerants, such as hydroxyapatite nanoparticles, tended to reduce the Injectability of the TCP pastes, especially if adjoined simultaneously with a Na2HPO4 solution. Although, as a general trend, faster-setting pastes were less injectable, some exceptions to this rule were found. For example, whereas in the absence of setting accelerants fine TCP powders were more injectable than the coarse ones, in spite of their shorter setting times, this trend was inverted when setting accelerants were added, and coarse powders were more injectable than the fine ones.
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novel soybean gelatine based bioactive and injectable hydroxyapatite foam material properties and cell response
Acta Biomaterialia, 2011Co-Authors: Francesca Perut, Josep Anton Planell, Maria-pau Ginebra, Edgar B. Montufar, G Ciapetti, Matteo Santin, Jonathan P Salvage, Tania Traykova, Nicola BaldiniAbstract:Despite their known osteoconductivity, clinical use of calcium phosphate cements is limited both by their relatively slow rate of resorption and by rheological properties incompatible with Injectability. Bone in-growth and material resorption have been improved by the development of porous calcium phosphate cements. However, injectable formulations have so far only been obtained through the addition of relatively toxic surfactants. The present work describes the response of osteoblasts to a novel injectable foamed bone cement based on a composite formulation including the bioactive foaming agents soybean and gelatine. The foaming properties of both defatted soybean and gelatine gels were exploited to develop a self-hardening soy/gelatine/hydroxyapatite composite foam able to retain porosity upon injection. After setting, the foamed paste produced a calcium-deficient hydroxyapatite scaffold, showing good Injectability and cohesion as well as interconnected porosity after injection. The intrinsic bioactivity of soybean and gelatine was shown to favour osteoblast adhesion and growth. These findings suggest that injectable, porous and bioactive calcium phosphate cements can be produced for bone regeneration through minimally invasive surgery.
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calcium phosphate cements as bone drug delivery systems a review
Journal of Controlled Release, 2006Co-Authors: Maria-pau Ginebra, Tania Traykova, Josep Anton PlanellAbstract:Since calcium phosphate cements were proposed, several formulations have been developed, some of them commercialised, and they have proven to be very efficient bone substitutes in different applications. Some of their properties, such as the Injectability, or the low-temperature setting, which allows the incorporation of different drugs, make them very attractive candidates as drug carriers. In this article, the performance of calcium phosphate cements as carriers of different types of drugs, such as antibiotics, analgesics, anticancer, anti-inflammatory, as well as growth factors is reviewed.
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Injectability of a macroporous calcium phosphate cement
Key Engineering Materials, 2005Co-Authors: J A Delgado, Josep Anton Planell, I Harr, Amisel Almirall, Sergio Del Valle, Maria-pau GinebraAbstract:In this work an injectable and self setting calcium phosphate/albumen foam is developed. The effect of both the amount of albumen and the particle size of the starting a-tricalcium phosphate (a-TCP) powder on the Injectability of the cement paste is studied. X-ray diffraction (XRD) and infrared (IR) analysis of the samples reveal that the hydrolysis of a-TCP to calcium deficient hydroxyapatite (CDHA) is not affected by the addition of albumen. A foamed structure formed by spherical pores with diameters between 100 and 500 µm is observed by SEM. This porous structure is maintained after injection of the paste, although some deformation of the pores is produced due to the extrusion process. The Injectability of the cements is increased by the presence of albumen as compared with cements prepared in the same conditions but without foaming agent.
Yingjun Wang - One of the best experts on this subject based on the ideXlab platform.
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improved Injectability and in vitro degradation of a calcium phosphate cement containing poly lactide co glycolide microspheres
Acta Biomaterialia, 2008Co-Authors: Yingjun WangAbstract:An injectable calcium phosphate cement (CPC) containing 30 wt.% poly(lactide-co-glycolide) (PLGA) microspheres was developed in the present study. Sodium citrate solution was used as the cement liquid phase. The effects of sodium citrate concentration on the Injectability, rheological properties, mechanical strength and self-setting properties of CPC containing PLGA microspheres were systematically investigated. The in vitro degradation behavior of the composite during immersion in phosphate buffer solution was also studied. With an increase in sodium citrate concentration, the viscosity and yield stress of the paste were reduced, thereby improving the Injectability. At a sodium citrate concentration of 15%, the Injectability of the paste reached 95%. The compressive strength of the specimen was also enhanced by the addition of sodium citrate. The specimens had a compressive strength of 32.24 ± 2.72 MPa at 15% sodium citrate concentration, compared to 22.15 ± 3.60 MPa for the specimen without sodium citrate. The in vitro degradation results demonstrate that incorporated PLGA microspheres can provide the required high strength to CPC in the early stage, which would gradually degrade to create macropores for bone ingrowth. In conclusion, an in situ macropore-generable CPC exhibited excellent Injectability and high early strength, and should be a promising material for bone repair and bone reconstruction.
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self setting properties of a β dicalcium silicate reinforced calcium phosphate cement
Journal of Biomedical Materials Research Part B, 2007Co-Authors: Xiupeng Wang, Jiandong Ye, Yingjun Wang, Ling ChenAbstract:β-Dicalcium silicate was used to reinforce the injectable calcium phosphate cement (iCPC) for the first time in this study. The influence of the content of β-dicalcium silicate on the mechanical properties, setting time, rheological properties, Injectability, phase evolution, microstructure, and biodegradability of iCPC was systematically investigated. The results demonstrated that the addition of 8 wt % β-dicalcium silicate obviously enhanced the compressive strength of the CPC from 26.5 to 47.5 MPa, and did not significantly influence the biodegradability, setting time, Injectability, phase evolution, and microstructure of the CPC. The β-dicalcium silicate-reinforced iCPC with relatively high mechanical property should have potential prospects for the wider applications in surgery such as orthopedics, oral, and maxillofacial surgery. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
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Rheological Properties and Injectability of a Calcium Phosphate Bone Substitute Material
Key Engineering Materials, 2005Co-Authors: Heng Chang Wang, Jiandong Ye, Xiao-ping Wang, Yingjun WangAbstract:A calcium phosphate bone substitute material was prepared and its rheological behavior and Injectability were studied in this work. The effects of temperature, L/P ratio and adjuvant on the rheological properties and Injectability of the pastes were discussed. The results show that the calcium phosphate bone substitute material is injectable with good fluidity and is suitable for the clinical applications. The rheological behavior and Injectability of the bone substitute material can be improved by adding adjuvants and optimizing L/P ratio.
Xiupeng Wang - One of the best experts on this subject based on the ideXlab platform.
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self setting properties of a β dicalcium silicate reinforced calcium phosphate cement
Journal of Biomedical Materials Research Part B, 2007Co-Authors: Xiupeng Wang, Jiandong Ye, Yingjun Wang, Ling ChenAbstract:β-Dicalcium silicate was used to reinforce the injectable calcium phosphate cement (iCPC) for the first time in this study. The influence of the content of β-dicalcium silicate on the mechanical properties, setting time, rheological properties, Injectability, phase evolution, microstructure, and biodegradability of iCPC was systematically investigated. The results demonstrated that the addition of 8 wt % β-dicalcium silicate obviously enhanced the compressive strength of the CPC from 26.5 to 47.5 MPa, and did not significantly influence the biodegradability, setting time, Injectability, phase evolution, and microstructure of the CPC. The β-dicalcium silicate-reinforced iCPC with relatively high mechanical property should have potential prospects for the wider applications in surgery such as orthopedics, oral, and maxillofacial surgery. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
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influence of anti washout agents on the rheological properties and Injectability of a calcium phosphate cement
Journal of Biomedical Materials Research Part B, 2007Co-Authors: Xiupeng Wang, Ling Chen, Hong XiangAbstract:Anti-washout-type calcium phosphate cement (aw-CPC) was prepared by introducing chitosan, sodium alginate, or modified starch into the powder phase of CPC, respectively. The results showed that these cements cannot be washed out and set within approximately 10-30 min even if the pastes were immersed in distilled water immediately and were shaken in a shaker after mixing and moulding. To our knowledge, it is the first report about the influence of the content of these anti-washout additives on the rheological properties and Injectability of the cement. Moreover, novel approach of yield stress measurement was used to evaluate the Injectability of the pastes. A modified starch was originally used as anti-washout agent for CPC. This study provided a convenient way to use the injectable CPC with good anti-washout performance when the paste was exposed to blood. The aw-CPC had potential prospects for the wider applications in surgery such as orthopaedics, oral, and maxillofacial surgery.
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influence of anti washout agents on the rheological properties and Injectability of a calcium phosphate cement
Journal of Biomedical Materials Research Part B, 2007Co-Authors: Xiupeng Wang, Ling Chen, Hong Xiang, Jiandong YeAbstract:Anti-washout-type calcium phosphate cement (aw-CPC) was prepared by introducing chitosan, sodium alginate, or modified starch into the powder phase of CPC, respectively. The results showed that these cements cannot be washed out and set within approximately 10–30 min even if the pastes were immersed in distilled water immediately and were shaken in a shaker after mixing and moulding. To our knowledge, it is the first report about the influence of the content of these anti-washout additives on the rheological properties and Injectability of the cement. Moreover, novel approach of yield stress measurement was used to evaluate the Injectability of the pastes. A modified starch was originally used as anti-washout agent for CPC. This study provided a convenient way to use the injectable CPC with good anti-washout performance when the paste was exposed to blood. The aw-CPC had potential prospects for the wider applications in surgery such as orthopaedics, oral, and maxillofacial surgery. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
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effects of additives on the rheological properties and Injectability of a calcium phosphate bone substitute material
Journal of Biomedical Materials Research Part B, 2006Co-Authors: Xiupeng Wang, Hai WangAbstract:An injectable calcium phosphate bone substitute material has been prepared by mixing amorphous calcium phosphate (ACP) and dicalcium phosphate dihydrate (DCPD) for use in noninvasive surgery, and the influence of additives, such as disodium hydrogen phosphate, polyethylene glycol (PEG), glycerin, and citric acid, on the rheological properties and Injectability of the ACP + DCPD cement system have been studied in this work. Novel approach of thixotropy measurement has been used to characterize the stability of the pastes. The results show that the Injectability and the setting time can be augmented by the addition of disodium phosphate solution to the paste but reduced by the addition of PEG 200, glycerin, or citric acid to the paste. This study suggests that the Injectability and the setting time of the ACP + DCPD bone substitute material can be balanced, and the injectable calcium phosphate bone substitute material with satisfied fluidity and Injectability for clinical operation can be prepared by optimizing the additives and their concentrations, according to different clinical requirements.