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John A. Jansen - One of the best experts on this subject based on the ideXlab platform.
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Stabilizing dental implants with a fiber-reinforced Calcium Phosphate Cement: an in vitro and in vivo study.
Acta Biomaterialia, 2020Co-Authors: Sónia De Lacerda Schickert, John A. Jansen, Ewald M. Bronkhorst, Jeroen J.j.p. Van Den Beucken, Sander C. G. LeeuwenburghAbstract:Abstract Stabilization of dental implants by means of biomaterials such as bioceramic granules and Cements is currently compromised by the poor mechanical properties of these bioceramics. Recently, our group developed a Calcium Phosphate Cement reinforced with poly(vinyl alcohol) fibers with improved flexural strength and toughness. Herein we evaluated the capacity of these fiber-reinforced Calcium Phosphate Cements to stabilize dental implants in vitro and in vivo using a range of mechanical and biological test methods. In vitro, filling of circumferential crestal peri-implant bone defects with synthetic bone analogues with fiber-reinforced Calcium Phosphate Cement demonstrated superior implant stability as compared to fiber-free Calcium Phosphate Cement over a 12-week period. Similarly, filling of circumferential crestal peri-implant bone defects with fiber-reinforced Calcium Phosphate Cement effectively stabilized dental implants installed in a rabbit femoral condyle defect as assessed via both implant stability quotient (ISQ) and torque-out measurements. Moreover, histological and histomorphometric evaluation demonstrated the osteocompatibility of fiber-reinforced Calcium Phosphate Cement, as evidenced by absence of soft tissue ingrowth, direct contact between the bone and Cement, and gradual degradation of the biomaterial and replaCement by newly-formed bone. These data demonstrate that fiber-reinforced Calcium Phosphate Cement stabilize dental implants during osseointegration.
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introduction of gelatin microspheres into an injectable Calcium Phosphate Cement
Journal of Biomedical Materials Research Part A, 2008Co-Authors: Wouter J E M Habraken, Antonios G. Mikos, L T De Jonge, J G C Wolke, Li Yubao, John A. JansenAbstract:For tissue engineered bone constructs, Calcium Phosphate Cement (CPC) has a high potential as scaffold material because of its biocompatibility and osteoconductivity. However, in vivo resorption and tissue ingrowth is slow. To address these issues, microspheres can be incorporated into the Cement, which will create macroporosity after in situ degradation. The goal of this study was to investigate the handling properties and degradation characteristics of CPC containing gelatin microspheres. Setting time and injectability were determined and an in vitro degradation study was performed. Samples were assayed on mass, compression strength, E-modulus, and morphology. A supplementary degradation test with gelatin microspheres was performed to investigate the influence of physical conditions inside the Cement on microsphere stability. The gelatin microsphere CPCs were easy to inject and showed initial setting times of less than 3 min. After 12-weeks in vitro degradation no increase in macroporosity was observed, which was supported by the small mass loss and stabilizing mechanical strength. Even a clear densification of the composite was observed. Explanations for the lack of macroporosity were recrystallization of the Cement onto or inside the gelatin spheres and a delayed degradation of gelatin microspheres inside the scaffold. The supplementary degradation test showed that the pH is a factor in the delayed gelatin microsphere degradation. Also differences in degradation rate between types of gelatin were observed. Overall, the introduction of gelatin microspheres into CPC renders composites with good handling properties, though the degradation characteristics should be further investigated to generate a macroporous scaffold.
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rhbmp 2 release from injectable poly dl lactic co glycolic acid Calcium Phosphate Cement composites
Journal of Bone and Joint Surgery American Volume, 2003Co-Authors: Quinten P Ruhe, Elizabeth L Hedberg, Nestor Torio Padron, Paul H. M. Spauwen, John A. Jansen, Antonios G. MikosAbstract:Background: In bone tissue engineering, poly(DL-lactic-co-glycolic acid) (PLGA) microparticles are frequently used as a delivery vehicle for bioactive molecules. Calcium Phosphate Cement is an injectable, osteoconductive,and degradable bone Cement that sets in situ. The objective of this study was to create an injectable composite based on Calcium Phosphate Cement embedded with PLGA microparticles for sustained delivery of recombinant human bone morphogenetic protein-2 (rhBMP-2). Methods: 1 2 5 I-labeled rhBMP-2 was incorporated in PLGA microparticles. PLGA microparticle/Calcium-Phosphate Cement composites were prepared in a ratio of 30:70 by weight. Material properties were evaluated by scanning electron microscopy, microcomputed tomography, and mechanical testing. Release kinetics of rhBMP-2 from PLGA/Calcium-Phosphate Cement disks and PLGA microparticles alone were determined in vitro in two buffer solutions (pH 7.4 and pH 4.0) for up to twenty-eight days. Results: The entrapment yield of rhBMP-2 in PLGA microparticles was a mean (and standard deviation) of 79% ′ 8%. Analysis showed spherical PLGA microparticles (average size, 17.2 ′1.3 μm) distributed homogeneously throughout the nanoporous disks. The average compressive strength was significantly lower (p < 0.001) for PLGA and Calcium-Phosphate Cement composite scaffolds than for Calcium-Phosphate Cement scaffolds alone (6.4 ′ 0.6 MPa compared with 38.6 ′ 2.6 MPa, respectively). Average rhBMP-2 loading was 5.0 ′ 0.4 μg per 75-mm 3 disk. Release of rhBMP-2 was limited for all formulations. At pH 7.4, 3.1% ′ 0.1% of the rhBMP-2 was released from the PLGA/Calcium-Phosphate Cement disks and 18.0% ′ 1.9% was released from the PLGA microparticles alone after twenty-eight days. At pH 4.0, PLGA/Calcium-Phosphate Cement disks revealed more release of rhBMP-2 than did PLGA microparticles alone (14.5% ′ 6.3% compared with 5.4% ′ 0.7%) by day 28. Conclusions: These results indicate that preparation of a PLGA/Calcium-Phosphate Cement composite for the delivery of rhBMP-2 is feasible and that the release of rhBMP-2 is dependent on the composite composition and nanostructure as well as the pH of the release medium. Clinical Relevance: An osteoconductive and osteoinductive rhBMP-2-loaded PLGA/Calcium-Phosphate Cement composite may potentially result in an injectable bone-graft substitute for the regeneration of bone in ectopic or orthotopic sites.
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in vivo bone response to porous Calcium Phosphate Cement
Journal of Biomedical Materials Research Part A, 2003Co-Authors: R P Del Real, J G C Wolke, E M Ooms, Maria Valletregi, John A. JansenAbstract:We conducted an in vivo experiment to evaluate the resorption rate of a Calcium Phosphate Cement (CPC) with macropores larger than 100 microm, using the CPC called BioCement D (Merck Biomaterial, Darmstadt, Germany), which after setting only shows pores smaller than 1 microm. The gas bubble method used during the setting process created macroporosity. Preset nonporous and porous Cement implants were inserted into the trabecular bone of the tibial metaphysis of goats. The size of the preset implants was 6 mm and the diameter of the drill hole was 6.3 mm, leaving a gap of 0.3 mm between implant surface and drill wall. After 2 and 10 weeks, the animals were euthanized and Cement implants with surrounding bone were retrieved for histologic evaluation. Light microscopy at 2 weeks revealed that the nonporous implants were surrounded by connective tissue. On the Cement surface, we observed a monolayer of multinucleated cells. Ten weeks after implantation, the nonporous implants were still surrounded by connective tissue. However, a thin layer of bone now covered the implant surface. No sign of Cement resorption was observed. In contrast, the porous Cement evoked a completely different bone response. At 2 weeks, bone formation had already occurred inside the implant porosity. Bone formation even appeared to occur as a result of osteoinduction. Also, at their outer surface, the porous implants were completely surrounded by bone. At 2 weeks, about 31% of the initial Cement was resorbed. After 10 weeks, 81% of the initial Phosphate Cement was resorbed and new bone was deposited. On the basis of these observations, we conclude that the creation of macropores can significantly improve the resorption rate of CPC. This increased degradation is associated with almost complete bone replaCement.
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rhBMP-2 release from injectable poly(DL-lactic-co-glycolic acid)/Calcium-Phosphate Cement composites.
The Journal of bone and joint surgery. American volume, 2003Co-Authors: P Quinten Ruhe, Elizabeth L Hedberg, Nestor Torio Padron, Paul H. M. Spauwen, John A. Jansen, Antonios G. MikosAbstract:In bone tissue engineering, poly(DL-lactic-co-glycolic acid) (PLGA) microparticles are frequently used as a delivery vehicle for bioactive molecules. Calcium Phosphate Cement is an injectable, osteoconductive, and degradable bone Cement that sets in situ. The objective of this study was to create an injectable composite based on Calcium Phosphate Cement embedded with PLGA microparticles for sustained delivery of recombinant human bone morphogenetic protein-2 (rhBMP-2).
Antonios G. Mikos - One of the best experts on this subject based on the ideXlab platform.
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introduction of gelatin microspheres into an injectable Calcium Phosphate Cement
Journal of Biomedical Materials Research Part A, 2008Co-Authors: Wouter J E M Habraken, Antonios G. Mikos, L T De Jonge, J G C Wolke, Li Yubao, John A. JansenAbstract:For tissue engineered bone constructs, Calcium Phosphate Cement (CPC) has a high potential as scaffold material because of its biocompatibility and osteoconductivity. However, in vivo resorption and tissue ingrowth is slow. To address these issues, microspheres can be incorporated into the Cement, which will create macroporosity after in situ degradation. The goal of this study was to investigate the handling properties and degradation characteristics of CPC containing gelatin microspheres. Setting time and injectability were determined and an in vitro degradation study was performed. Samples were assayed on mass, compression strength, E-modulus, and morphology. A supplementary degradation test with gelatin microspheres was performed to investigate the influence of physical conditions inside the Cement on microsphere stability. The gelatin microsphere CPCs were easy to inject and showed initial setting times of less than 3 min. After 12-weeks in vitro degradation no increase in macroporosity was observed, which was supported by the small mass loss and stabilizing mechanical strength. Even a clear densification of the composite was observed. Explanations for the lack of macroporosity were recrystallization of the Cement onto or inside the gelatin spheres and a delayed degradation of gelatin microspheres inside the scaffold. The supplementary degradation test showed that the pH is a factor in the delayed gelatin microsphere degradation. Also differences in degradation rate between types of gelatin were observed. Overall, the introduction of gelatin microspheres into CPC renders composites with good handling properties, though the degradation characteristics should be further investigated to generate a macroporous scaffold.
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rhbmp 2 release from injectable poly dl lactic co glycolic acid Calcium Phosphate Cement composites
Journal of Bone and Joint Surgery American Volume, 2003Co-Authors: Quinten P Ruhe, Elizabeth L Hedberg, Nestor Torio Padron, Paul H. M. Spauwen, John A. Jansen, Antonios G. MikosAbstract:Background: In bone tissue engineering, poly(DL-lactic-co-glycolic acid) (PLGA) microparticles are frequently used as a delivery vehicle for bioactive molecules. Calcium Phosphate Cement is an injectable, osteoconductive,and degradable bone Cement that sets in situ. The objective of this study was to create an injectable composite based on Calcium Phosphate Cement embedded with PLGA microparticles for sustained delivery of recombinant human bone morphogenetic protein-2 (rhBMP-2). Methods: 1 2 5 I-labeled rhBMP-2 was incorporated in PLGA microparticles. PLGA microparticle/Calcium-Phosphate Cement composites were prepared in a ratio of 30:70 by weight. Material properties were evaluated by scanning electron microscopy, microcomputed tomography, and mechanical testing. Release kinetics of rhBMP-2 from PLGA/Calcium-Phosphate Cement disks and PLGA microparticles alone were determined in vitro in two buffer solutions (pH 7.4 and pH 4.0) for up to twenty-eight days. Results: The entrapment yield of rhBMP-2 in PLGA microparticles was a mean (and standard deviation) of 79% ′ 8%. Analysis showed spherical PLGA microparticles (average size, 17.2 ′1.3 μm) distributed homogeneously throughout the nanoporous disks. The average compressive strength was significantly lower (p < 0.001) for PLGA and Calcium-Phosphate Cement composite scaffolds than for Calcium-Phosphate Cement scaffolds alone (6.4 ′ 0.6 MPa compared with 38.6 ′ 2.6 MPa, respectively). Average rhBMP-2 loading was 5.0 ′ 0.4 μg per 75-mm 3 disk. Release of rhBMP-2 was limited for all formulations. At pH 7.4, 3.1% ′ 0.1% of the rhBMP-2 was released from the PLGA/Calcium-Phosphate Cement disks and 18.0% ′ 1.9% was released from the PLGA microparticles alone after twenty-eight days. At pH 4.0, PLGA/Calcium-Phosphate Cement disks revealed more release of rhBMP-2 than did PLGA microparticles alone (14.5% ′ 6.3% compared with 5.4% ′ 0.7%) by day 28. Conclusions: These results indicate that preparation of a PLGA/Calcium-Phosphate Cement composite for the delivery of rhBMP-2 is feasible and that the release of rhBMP-2 is dependent on the composite composition and nanostructure as well as the pH of the release medium. Clinical Relevance: An osteoconductive and osteoinductive rhBMP-2-loaded PLGA/Calcium-Phosphate Cement composite may potentially result in an injectable bone-graft substitute for the regeneration of bone in ectopic or orthotopic sites.
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rhBMP-2 release from injectable poly(DL-lactic-co-glycolic acid)/Calcium-Phosphate Cement composites.
The Journal of bone and joint surgery. American volume, 2003Co-Authors: P Quinten Ruhe, Elizabeth L Hedberg, Nestor Torio Padron, Paul H. M. Spauwen, John A. Jansen, Antonios G. MikosAbstract:In bone tissue engineering, poly(DL-lactic-co-glycolic acid) (PLGA) microparticles are frequently used as a delivery vehicle for bioactive molecules. Calcium Phosphate Cement is an injectable, osteoconductive, and degradable bone Cement that sets in situ. The objective of this study was to create an injectable composite based on Calcium Phosphate Cement embedded with PLGA microparticles for sustained delivery of recombinant human bone morphogenetic protein-2 (rhBMP-2).
Maria-pau Ginebra - One of the best experts on this subject based on the ideXlab platform.
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porous hydroxyapatite and gelatin hydroxyapatite microspheres obtained by Calcium Phosphate Cement emulsion
Journal of Biomedical Materials Research Part B, 2011Co-Authors: George Altankov, Roman A. Perez, Maria-pau Ginebra, Sergio Del ValleAbstract:Hydroxyapatite and hybrid gelatine/hydroxyapatite microspheres were obtained through a water in oil emulsion of a Calcium Phosphate Cement (CPC). The setting reaction of the CPC, in this case the hydrolysis of α-triCalcium Phosphate, was responsible for the consolidation of the microspheres. After the setting reaction, the microspheres consisted of an entangled network of hydroxyapatite crystals, with a high porosity and pore sizes ranging between 0.5 and 5 μm. The size of the microspheres was tailored by controlling the viscosity of the hydrophobic phase, the rotation speed, and the initial powder size of the CPC. The incorporation of gelatin increased the sphericity of the microspheres, as well as their size and size dispersion. To assess the feasibility of using the microspheres as cell microcarriers, Saos-2 cells were cultured on the microspheres. Fluorescent staining, SEM studies, and LDH quantification showed that the microspheres were able to sustain cell growth. Cell adhesion and proliferation was significantly improved in the hybrid gelatin/hydroxyapatite microspheres as compared to the hydroxyapatite ones. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.
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Porous hydroxyapatite and gelatin/hydroxyapatite microspheres obtained by Calcium Phosphate Cement emulsion
Journal of Biomedical Materials Research - Part B Applied Biomaterials, 2011Co-Authors: Roman A. Perez, Sergio Del Valle, George Altankov, Maria-pau GinebraAbstract:Hydroxyapatite and hybrid gelatine/hydroxyapatite microspheres were obtained through a water in oil emulsion of a Calcium Phosphate Cement (CPC). The setting reaction of the CPC, in this case the hydrolysis of α-triCalcium Phosphate, was responsible for the consolidation of the microspheres. After the setting reaction, the microspheres consisted of an entangled network of hydroxyapatite crystals, with a high porosity and pore sizes ranging between 0.5 and 5 μm. The size of the microspheres was tailored by controlling the viscosity of the hydrophobic phase, the rotation speed, and the initial powder size of the CPC. The incorporation of gelatin increased the sphericity of the microspheres, as well as their size and size dispersion. To assess the feasibility of using the microspheres as cell microcarriers, Saos-2 cells were cultured on the microspheres. Fluorescent staining, SEM studies, and LDH quantification showed that the microspheres were able to sustain cell growth. Cell adhesion and proliferation was significantly improved in the hybrid gelatin/hydroxyapatite microspheres as compared to the hydroxyapatite ones.
Hockin H K Xu - One of the best experts on this subject based on the ideXlab platform.
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gas foaming Calcium Phosphate Cement scaffold encapsulating human umbilical cord stem cells
Tissue Engineering Part A, 2012Co-Authors: Wenchuan Chen, Michael D Weir, Hongzhi Zhou, Minghui Tang, Hockin H K XuAbstract:Tissue engineering approaches are promising to meet the increasing need for bone regeneration. Calcium Phosphate Cement (CPC) can be injected and self-set to form a scaffold with excellent osteoconductivity. The objectives of this study were to develop a macroporous CPC–chitosan–fiber construct containing alginate–fibrin microbeads encapsulating human umbilical cord mesenchymal stem cells (hUCMSCs) and to investigate hUCMSC release from the degrading microbeads and proliferation inside the porous CPC construct. The hUCMSC-encapsulated microbeads were completely wrapped inside the CPC paste, with the gas-foaming porogen creating macropores in CPC to provide for access to culture media. Increasing the porogen content in CPC significantly increased the cell viability, from 49% of live cells in CPC with 0% porogen to 86% of live cells in CPC with 15% porogen. The alginate–fibrin microbeads started to degrade and release the cells inside CPC at 7 days. The released cells started to proliferate inside the macro...
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collagen Calcium Phosphate Cement scaffolds seeded with umbilical cord stem cells for bone tissue engineering
Tissue Engineering Part A, 2011Co-Authors: Wahwah Theinhan, Hockin H K XuAbstract:Human umbilical cord mesenchymal stem cells (hUCMSCs) avoid the invasive procedure required to harvest bone marrow MSCs. The addition of collagen fibers into self-setting Calcium Phosphate Cement (CPC) may increase the scaffold strength, and enhance cell attachment and differentiation. The objectives of this study were to develop a novel class of collagen-CPC composite scaffolds, and to investigate hUCMSC attachment, proliferation, and osteogenic differentiation on collagen-CPC scaffolds for the first time. Collagen fibers in CPC improved the load-bearing capability. Flow cytometry showed that the hUCMSCs expressed cell surface markers characteristic of MSCs, and were negative for hematopoietic and endothelial cell markers. hUCMSCs proliferated rapidly in all CPC composite scaffolds, with cell number increasing by sevenfold in 8 days. Cellular function was enhanced with collagen fibers in CPC scaffolds. Cell density increased from (645±60) cells/mm2 on CPC with 0% collagen, to (1056±65) cells/mm2 on CPC w...
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injectable and macroporous Calcium Phosphate Cement scaffold
Biomaterials, 2006Co-Authors: Hockin H K Xu, Michael D Weir, Elena F Burguera, Alexis M FraserAbstract:Calcium Phosphate Cement (CPC) can be molded and self-hardens in vivo to form resorbable hydroxyapatite with excellent osteoconductivity. The objective of this study was to develop an injectable, macroporous and strong CPC, and to investigate the effects of porogen and absorbable fibers. Water-soluble mannitol was used as porogen and mixed with CPC at mass fractions from 0% to 50%. CPC with 0–40% mannitol was fully extruded under a syringe force of 10 n. The paste with 50% mannitol required a 100-N force which extruded only 66% of the paste. At fiber volume fraction of 0–5%, the paste was completely extruded. However, at 6% and 7.5% fibers, some fibers were left in the syringe after the paste was extruded. The injectable CPC scaffold had a flexural strength (mean±sd; n=5n=5) of (3.2±1.0) MPa, which approached the reported strengths for sintered porous hydroxyapatite implants and cancellous bone. In summary, the injectability of a ceramic scaffold, a macroporous CPC, was studies for the first time. Processing parameters were tailored to achieve high injectability, macroporosity, and strength. The injectable and strong CPC scaffold may be useful in surgical sites that are not freely accessible by open surgery or when using minimally invasive techniques.
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reinforCement of a self setting Calcium Phosphate Cement with different fibers
Journal of Biomedical Materials Research, 2000Co-Authors: Hockin H K Xu, Frederick C Eichmiller, Anthony A GiuseppettiAbstract:A water-based Calcium Phosphate Cement (CPC) has been used in a number of medical and dental procedures due to its excellent osteoconductivity and bone replaCement capability. However, the low tensile strength of CPC prohibits its use in many unsupported defects and stress-bearing locations. Little investigation has been carried out on the fiber reinforCement of CPC. The aims of the present study, therefore, were to examine whether fibers would strengthen CPC, and to investigate the effects of fiber type, fiber length, and volume fraction. Four different fibers were used: aramid, carbon, E-glass, and polyglactin. Fiber length ranged from 3–200 mm, and fiber volume fraction ranged from 1.9–9.5%. The fibers were mixed with CPC paste and placed into molds of 3 × 4 × 25 mm. A flexural test was used to fracture the set specimens and to measure the ultimate strength, work-of-fracture, and elastic modulus. Scanning electron microscopy was used to examine specimen fracture surfaces. Fiber type had significant effects on composite properties. The composite ultimate strength in MPa (mean ± SD; n = 6) was (62 ± 16) for aramid, (59 ± 11) for carbon, (29 ± 8) for E-glass, and (24 ± 4) for polyglactin, with 5.7% volume fraction and 75 mm fiber length. In comparison, the strength of unreinforced CPC was (13 ± 3). Fiber length also played an important role. For composites containing 5.7% aramid fibers, the ultimate strength was (24 ± 3) for 3 mm fibers, (36 ± 13) for 8 mm fibers, (48 ± 14) for 25 mm fibers, and (62 ± 16) for 75 mm fibers. At 25 mm fiber length, the ultimate strength of CPC composite was found to be linearly proportional to fiber strength. In conclusion, a self-setting Calcium Phosphate Cement was substantially strengthened via fiber reinforCement. Fiber length, fiber volume fraction, and fiber strength were found to be key microstructural parameters that controlled the mechanical properties of CPC composites. © 2000 John Wiley & Sons, Inc. J Biomed Mater Res, 52, 107–114, 2000.
Roman A. Perez - One of the best experts on this subject based on the ideXlab platform.
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porous hydroxyapatite and gelatin hydroxyapatite microspheres obtained by Calcium Phosphate Cement emulsion
Journal of Biomedical Materials Research Part B, 2011Co-Authors: George Altankov, Roman A. Perez, Maria-pau Ginebra, Sergio Del ValleAbstract:Hydroxyapatite and hybrid gelatine/hydroxyapatite microspheres were obtained through a water in oil emulsion of a Calcium Phosphate Cement (CPC). The setting reaction of the CPC, in this case the hydrolysis of α-triCalcium Phosphate, was responsible for the consolidation of the microspheres. After the setting reaction, the microspheres consisted of an entangled network of hydroxyapatite crystals, with a high porosity and pore sizes ranging between 0.5 and 5 μm. The size of the microspheres was tailored by controlling the viscosity of the hydrophobic phase, the rotation speed, and the initial powder size of the CPC. The incorporation of gelatin increased the sphericity of the microspheres, as well as their size and size dispersion. To assess the feasibility of using the microspheres as cell microcarriers, Saos-2 cells were cultured on the microspheres. Fluorescent staining, SEM studies, and LDH quantification showed that the microspheres were able to sustain cell growth. Cell adhesion and proliferation was significantly improved in the hybrid gelatin/hydroxyapatite microspheres as compared to the hydroxyapatite ones. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.
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Porous hydroxyapatite and gelatin/hydroxyapatite microspheres obtained by Calcium Phosphate Cement emulsion
Journal of Biomedical Materials Research - Part B Applied Biomaterials, 2011Co-Authors: Roman A. Perez, Sergio Del Valle, George Altankov, Maria-pau GinebraAbstract:Hydroxyapatite and hybrid gelatine/hydroxyapatite microspheres were obtained through a water in oil emulsion of a Calcium Phosphate Cement (CPC). The setting reaction of the CPC, in this case the hydrolysis of α-triCalcium Phosphate, was responsible for the consolidation of the microspheres. After the setting reaction, the microspheres consisted of an entangled network of hydroxyapatite crystals, with a high porosity and pore sizes ranging between 0.5 and 5 μm. The size of the microspheres was tailored by controlling the viscosity of the hydrophobic phase, the rotation speed, and the initial powder size of the CPC. The incorporation of gelatin increased the sphericity of the microspheres, as well as their size and size dispersion. To assess the feasibility of using the microspheres as cell microcarriers, Saos-2 cells were cultured on the microspheres. Fluorescent staining, SEM studies, and LDH quantification showed that the microspheres were able to sustain cell growth. Cell adhesion and proliferation was significantly improved in the hybrid gelatin/hydroxyapatite microspheres as compared to the hydroxyapatite ones.
