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Lee H, Jang TS, Song J, Kim HE, Jung HD. The Production of Porous Hydroxyapatite Scaffolds with Graded Porosity by Sequential Freeze-Casting. MATERIALS (BASEL, SWITZERLAND) 2017; 10:E367. [PMID: 28772735 PMCID: PMC5506897 DOI: 10.3390/ma10040367] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 03/15/2017] [Accepted: 03/27/2017] [Indexed: 11/23/2022]
Abstract
Porous hydroxyapatite (HA) scaffolds with porosity-graded structures were fabricated by sequential freeze-casting. The pore structures, compressive strengths, and biocompatibilities of the fabricated porous HA scaffolds were evaluated. The porosities of the inner and outer layers of the graded HA scaffolds were controlled by adjusting the initial HA contents of the casting slurries. The interface between the dense and porous parts was compact and tightly adherent. The porosity and compressive strengths of the scaffold were controlled by the relative thicknesses of the dense/porous parts. In addition, the porous HA scaffolds showed good biocompatibility in terms of preosteoblast cell attachment and proliferation. The results suggest that porous HA scaffolds with load-bearing parts have potential as bone grafts in hard-tissue engineering.
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Jang TS, Jung HD, Kim S, Moon BS, Baek J, Park C, Song J, Kim HE. Multiscale porous titanium surfaces via a two-step etching process for improved mechanical and biological performance. Biomed Mater 2017; 12:025008. [DOI: 10.1088/1748-605x/aa5d74] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Kim S, Park C, Moon BS, Kim HE, Jang TS. Enhancement of osseointegration by direct coating of rhBMP-2 on target-ion induced plasma sputtering treated SLA surface for dental application. J Biomater Appl 2016; 31:807-818. [DOI: 10.1177/0885328216679761] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Owing to the excellent bioactive properties of recombinant human bone morphogenetic proteins (rhBMPs), dentistry considers them as a fascinating adjuvant alternative for enhancing bone regeneration and bone-to-implant junction in the early implantation stages. However, stable loading and delivery efficiency of rhBMPs on the implant surfaces involve major concerns because of the harsh wearing condition under load during implantation. In this study, to achieve successful rhBMP-2 delivery, a nanoporous surface structure is introduced on the sandblasting with large grit and acid-etching (SLA)-treated titanium (Ti) surface via the tantalum (Ta) target-ion induced plasma sputtering (TIPS) technique. Unlike oxidation-induced surface nanoporous fabrications on a Ti surface, TIPS-treated surfaces provide excellent structural unity of the nanoporous structure with the substrate due to their etching-based fabrication mechanism. SLA/TIPS-treated Ti exhibits distinct nanoporous structures on the microscale surface geometry and better hydrophilicity compared with SLA-treated Ti. A sufficiently empty nanoporous surface structure combined with the hydrophilic property of SLA/TIPS-treated Ti facilitates the formation of a thick and uniform coating layer of rhBMP-2 on the surface without any macro- and microcoagulation. Compared with the SLA-treated Ti surface, the amount of coated rhBMP-2 increases up to 63% on the SLA/TIPS-treated Ti surface. As a result, the in vitro pre-osteoblast cell response of the SLA/TIPS-treated Ti surface, especially cell adhesion and differentiation behaviors, improves remarkably. A bone-regenerating direct comparison between the rhBMP-2-coated SLA-treated and SLA/TIPS-treated Ti is conducted on a defective dog mandible model. After 8 weeks of implantation surgery, SLA/TIPS-treated Ti with rhBMP-2 exhibits a better degree of contact area for the implanted bone, which mineralizes new bones around the implant. Quantitative results of bone-in-contact ratio and new bone volume also show significantly higher values for the SLA/TIPS-treated Ti with the rhBMP-2 specimen. These results confirm that an SLA/TIPS-treated surface is a suitable rhBMP-2 carrier for a dental implant to achieve early and strong osseointegration of Ti dental implants.
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Jeong SH, Fan YF, Baek JU, Song J, Choi TH, Kim SW, Kim HE. Long-lasting and bioactive hyaluronic acid-hydroxyapatite composite hydrogels for injectable dermal fillers: Physical properties and in vivo durability. J Biomater Appl 2016; 31:464-74. [DOI: 10.1177/0885328216648809] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Hyaluronic acid (HAc)–hydroxyapatite (HAp) composite hydrogels were developed to improve the biostability and bioactivity of HAc for dermal filler applications. Two kinds of HAc-HAp composite fillers were generated: HAcmicroHAp and HAc-nanoHAp composites. HAc-microHAp was fabricated by mixing HAp microspheres with HAc hydrogels, and HAc-nanoHAp was made by in situ precipitation of nano-sized HAp particles in HAc hydrogels. Emphasis was placed on the effect of HAp on the durability and bioactivity of the fillers. Compared with the pure HAc filler, all of the HAc-HAp composite fillers exhibited significant improvements in volumetric maintenance based on in vivo tests owing to their reduced water content and higher degree of biointegration between the filler and surrounding tissues. HAc-HAp composite fillers also showed noticeable enhancement in dermis recovery, promoting collagen and elastic fiber formation. Based on their long-lasting durability and bioactivity, HAc-HAp composite fillers have great potential for soft tissue augmentation with multifunctionality.
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Abstract
A hydroxyapatite (HA)-titania (TiO2) hybrid coating is developed to improve the biocompatibility of titanium (Ti) implants. The HA predeposited layer on Ti via electron beam (e-beam) evaporation is subsequently treated by micro-arc oxidation (MAO) to produce an HA-TiO2 hybrid layer on Ti. The e-beam-deposited HA layer has a thickness of ≈1 μm and was highly dense prior to MAO. By means of MAO treatment, a rough and porous TiO2 layer is formed beneath the HA layer with a simultaneous local dissolution of the HA layer. Due to the HA precoating, high concentrations of Ca and P are preserved on the coating surface. The osteoblast-like cells on the hybrid coating layer grow and spread favorably. The cell proliferation rate on the hybrid coatings is not much different from that on pure Ti or simple MAO-treated Ti. However, the alkaline phosphatase (ALP) activity of the cells is significantly higher ( p < 0.05) on the HA-TiO2 hybrid coatings than on either the pure Ti or the simple MAO-treated specimen, suggesting that the cellular activity on the hybrid coatings is improved.
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Park JU, Jung HD, Song EH, Choi TH, Kim HE, Song J, Kim S. The accelerating effect of chitosan-silica hybrid dressing materials on the early phase of wound healing. J Biomed Mater Res B Appl Biomater 2016; 105:1828-1839. [PMID: 27219872 DOI: 10.1002/jbm.b.33711] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 04/21/2016] [Accepted: 05/01/2016] [Indexed: 11/09/2022]
Abstract
Commercialized dressing materials with or without silver have played a passive role in early-phase wound healing, protecting the skin defects from infections, absorbing exudate, and preventing dehydration. Chitosan (CTS)-based sponges have been developed in pure or hybrid forms for accelerating wound healing, but their wound-healing capabilities have not been extensively compared with widely used commercial dressing materials, providing limited information in a practical aspect. In this study, we have developed CTS-silica (CTS-Si) hybrid sponges with water absorption, flexibility, and mechanical behavior similar to those of CTS sponges. In vitro and in vivo tests were performed to compare the CTS-Si sponges with three commercial dressing materials [gauze, polyurethane (PU), and silver-containing hydrofiber (HF-Ag)] in addition to CTS sponges. Both in vitro and in vivo tests showed that CTS-Si sponges promoted fibroblast proliferation, leading to accelerated collagen synthesis, whereas the CTS sponges did not exhibit significant differences in fibroblast proliferation and collagen synthesis from gauze, PU, and HF-Ag sponges. In case of CTS-Si, the inflammatory cells were actively recruited to the wound by the influence of the released silicon ions from CTS-Si sponges, which, in return, led to an enhanced secretion of growth factors, particularly TGF-β during the early stage. The higher level of TGF-β likely improved the proliferation of fibroblasts, and as a result, collagen synthesis by fibroblasts became remarkably productive, thereby increasing collagen density at the wound site. Therefore, the CTS-Si hybrid sponges have considerable potential as a wound-dressing material for accelerating wound healing. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1828-1839, 2017.
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Lim HK, Byun SH, Lee JY, Lee JW, Kim SM, Lee SM, Kim HE, Lee JH. Radiological, histological, and hematological evaluation of hydroxyapatite-coated resorbable magnesium alloy screws placed in rabbit tibia. J Biomed Mater Res B Appl Biomater 2016; 105:1636-1644. [PMID: 27174442 DOI: 10.1002/jbm.b.33703] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 03/15/2016] [Accepted: 04/21/2016] [Indexed: 11/11/2022]
Abstract
Titanium (Ti) screw has excellent mechanical property, and osseointegration capacity. However, they require surgery for removal. In contrast, polymer screws are resorbable, but they have poor mechanical properties. In this research, magnesium alloy screws (WE43: Mg-Y-Nd-Zr) that have advantages of titanium and polymer were manufactured. In addition, to increase biocompatibility and control degradation rate, the Mg alloy was coated with hydroxyapatite (HA). Torsion test and corrosion test were performed in vitro. For clinical, radiological and histological evaluation, on the eight rabbits, two HA-coated screws were installed in left tibia, and two noncoated screws were installed in right tibia. Each four rabbits were sacrificed 6 and 12 weeks postoperatively. For hematological evaluation, the same type of screws were installed on both legs. Complete blood count (CBC), Mg2+ concentrate were sampled from the ear central artery on the operation day for a control point, and at 1, 2, 4, 6, 8, and 12 weeks. Mg alloy screws have no differences of biocompatibility according to the HA coating. However, resorption of screw was slower in case of the HA coating. The hematological problem related releasing of Mg was not found. The results suggest that Mg alloy screws have feasibility for clinical application. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1636-1644, 2017.
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Kang MH, Jang TS, Jung HD, Kim SM, Kim HE, Koh YH, Song J. Poly(ether imide)-silica hybrid coatings for tunable corrosion behavior and improved biocompatibility of magnesium implants. ACTA ACUST UNITED AC 2016; 11:035003. [PMID: 27147643 DOI: 10.1088/1748-6041/11/3/035003] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Magnesium (Mg) and its alloys have gained considerable attention as a promising biomaterial for bioresorbable orthopedic implants, but the corrosion behavior of Mg-based implants is still the major issue for clinical use. In order to improve the corrosion stability and implant-tissue interfaces of these implants, methods for coating Mg have been actively investigated. In this study, poly(ether imide) (PEI)-silica hybrid material was coated on Mg, for the tunable degradation and enhanced biological behavior. Homogeneous PEI-silica hybrid materials with various silica contents were coated on Mg substrates without any cracks, where silica nanoparticles were well dispersed in the PEI matrix without significant particle agglomeration up the 30 vol% silica. The hybrid coatings maintained good adhesion strength of PEI to Mg. The corrosion rate of hybrid-coated Mg was increased along with the increment of the silica content, due to improved hydrophilicity of the hybrid coating layers. Moreover, the biocompatibility of the hybrid-coated Mg specimens was significantly improved, mainly due to the higher Mg ion concentrations associated with faster corrosion, compared to PEI-coated Mg. Therefore, PEI-silica hybrid systems have significant potential as a coating material of Mg for load-bearing orthopedic applications by providing tunable corrosion behavior and enhanced biological performance.
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Jeong SH, Koh YH, Kim SW, Park JU, Kim HE, Song J. Strong and Biostable Hyaluronic Acid-Calcium Phosphate Nanocomposite Hydrogel via in Situ Precipitation Process. Biomacromolecules 2016; 17:841-51. [PMID: 26878437 DOI: 10.1021/acs.biomac.5b01557] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Hyaluronic acid (HAc) hydrogel exhibits excellent biocompatibility, but it has limited biomedical application due to its poor biomechanical properties as well as too-fast enzymatic degradation. In this study, we have developed an in situ precipitation process for the fabrication of a HAc-calcium phosphate nanocomposite hydrogel, after the formation of the glycidyl methacrylate-conjugated HAc (GMHA) hydrogels via photo-cross-linking, to improve the mechanical and biological properties under physiological conditions. In particular, our process facilitates the rapid incorporation of calcium phosphate (CaP) nanoparticles of uniform size and with minimal agglomeration into a polymer matrix, homogeneously. Compared with pure HAc, the nanocomposite hydrogels exhibit improved mechanical behavior. Specifically, the shear modulus is improved by a factor of 4. The biostability of the nanocomposite hydrogel was also significantly improved compared with that of pure HAc hydrogels under both in vitro and in vivo conditions.
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Diez M, Kang MH, Kim SM, Kim HE, Song J. Hydroxyapatite (HA)/poly-L-lactic acid (PLLA) dual coating on magnesium alloy under deformation for biomedical applications. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2016; 27:34. [PMID: 26704551 DOI: 10.1007/s10856-015-5643-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 12/07/2015] [Indexed: 06/05/2023]
Abstract
The introduction of a protective coating layer to highly corrosive magnesium (Mg) has been proposed as one of the common approaches for improved corrosion resistance of Mg-based implants as load-bearing biomedical applications. However, only few studies have focused on the mechanical stability of the coated Mg under practical conditions where significant deformation of the load-bearing implants is induced during the surgical operation or under physiological environments. Therefore, in this study, we developed a dual coating system composed of an interlayer hydroxyapatite (HA) and a top layer poly-L-lactic acid (PLLA) to improve the coating stability under deformation of Mg alloy (WE43) substrate. The HA interlayer was directly formed on the Mg alloy surface, followed by dip-coating of PLLA. As the interlayer, HA improved the adhesion of PLLA by modulating nano- and microscale roughness, in addition to its inherently good bonding strength to Mg. The flexible and deformable top coating PLLA layer mitigated crack propagation in the HA layer under deformation. Thus, the dual coating layer provided good protection to the underlying WE43 from corrosion regardless of deformation. The enhanced corrosion behavior of dual-coated WE43 exhibited better mechanical and biological performance compared to the non-coated or single-coated WE43. Therefore, this dual coating layer on Mg is expected to accelerate Mg-based applications in biomedical devices.
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Lee EJ, Kim HE. Accelerated bony defect healing by chitosan/silica hybrid membrane with localized bone morphogenetic protein-2 delivery. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2016; 59:339-345. [DOI: 10.1016/j.msec.2015.10.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 09/14/2015] [Accepted: 10/01/2015] [Indexed: 11/28/2022]
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Qi Y, Contreras KG, Jung HD, Kim HE, Lapovok R, Estrin Y. Ultrafine-grained porous titanium and porous titanium/magnesium composites fabricated by space holder-enabled severe plastic deformation. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2016; 59:754-765. [DOI: 10.1016/j.msec.2015.10.070] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 10/15/2015] [Accepted: 10/23/2015] [Indexed: 10/22/2022]
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Kang MH, Jang TS, Kim SW, Park HS, Song J, Kim HE, Jung KH, Jung HD. MgF2-coated porous magnesium/alumina scaffolds with improved strength, corrosion resistance, and biological performance for biomedical applications. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2016; 62:634-42. [PMID: 26952467 DOI: 10.1016/j.msec.2016.01.085] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 01/20/2016] [Accepted: 01/28/2016] [Indexed: 11/19/2022]
Abstract
Porous magnesium (Mg) has recently emerged as a promising biodegradable alternative to biometal for bone ingrowth; however, its low mechanical properties and high corrosion rate in biological environments remain problematic. In this study, porous magnesium was implemented in a scaffold that closely mimics the mechanical properties of human bones with a controlled degradation rate and shows good biocompatibility to match the regeneration rate of bone tissue at the affected site. The alumina-reinforced Mg scaffold was produced by spark plasma sintering and coated with magnesium fluoride (MgF2) using a hydrofluoric acid solution to regulate the corrosion rate under physiological conditions. Sodium chloride granules (NaCl), acting as space holders, were leached out to achieve porous samples (60%) presenting an average pore size of 240 μm with complete pore interconnectivity. When the alumina content increased from 0 to 5 vol%, compressive strength and stiffness rose considerably from 9.5 to 13.8 MPa and from 0.24 to 0.40 GPa, respectively. Moreover, the biological response evaluated by in vitro cell test and blood test of the MgF2-coated porous Mg composite was enhanced with better corrosion resistance compared with that of uncoated counterparts. Consequently, MgF2-coated porous Mg/alumina composites may be applied in load-bearing biodegradable implants.
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Jang TS, Kim S, Jung HD, Chung JW, Kim HE, Koh YH, Song J. Large-scale nanopatterning of metal surfaces by target-ion induced plasma sputtering (TIPS). RSC Adv 2016. [DOI: 10.1039/c6ra00443a] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Target-ion Induced Plasma Sputtering (TIPS) can produce large-scale, self-assembled nanopatterns on metals and alloys in one step at low cost.
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Jung HD, Lee H, Kim HE, Koh YH, Song J. Fabrication of Mechanically Tunable and Bioactive Metal Scaffolds for Biomedical Applications. J Vis Exp 2015:e53279. [PMID: 26709604 DOI: 10.3791/53279] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Biometal systems have been widely used for biomedical applications, in particular, as load-bearing materials. However, major challenges are high stiffness and low bioactivity of metals. In this study, we have developed a new method towards fabricating a new type of bioactive and mechanically reliable porous metal scaffolds-densified porous Ti scaffolds. The method consists of two fabrication processes, 1) the fabrication of porous Ti scaffolds by dynamic freeze casting, and 2) coating and densification of the porous scaffolds. The dynamic freeze casting method to fabricate porous Ti scaffolds allowed the densification of porous scaffolds by minimizing the chemical contamination and structural defects. The densification process is distinctive for three reasons. First, the densification process is simple, because it requires a control of only one parameter (degree of densification). Second, it is effective, as it achieves mechanical enhancement and sustainable release of biomolecules from porous scaffolds. Third, it has broad applications, as it is also applicable to the fabrication of functionally graded porous scaffolds by spatially varied strain during densification.
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Choi WY, Kim HE, Moon YW, Shin KH, Koh YH. Production of porous Calcium Phosphate (CaP) ceramics with aligned pores using ceramic/camphene-based co-extrusion. Biomater Res 2015; 19:16. [PMID: 26331085 PMCID: PMC4552288 DOI: 10.1186/s40824-015-0037-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 06/09/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Calcium phosphate (CaP) ceramics are one of the most valuable biomaterials for uses as the bone scaffold owing to their outstanding biocompatability, bioactivity, and biodegradation nature. In particular, these materials with an open porous structure can stimulate bone ingrowth into their 3-dimensionally interconnected pores. However, the creation of pores in bulk materials would inevitably cause a severe reduction in mechanical properties. Thus, it is a challenge to explore new ways of improving the mechanical properties of porous CaP scaffolds without scarifying their high porosity. RESULTS Porous CaP ceramic scaffolds with aligned pores were successfully produced using ceramic/camphene-based co-extrusion. This aligned porous structure allowed for the achievement of high compressive strength when tested parallel to the direction of aligned pores. In addition, the overall porosity and mechanical properties of the aligned porous CaP ceramic scaffolds could be tailored simply by adjusting the initial CaP content in the CaP/camphene slurry. The porous CaP scaffolds showed excellent in vitro biocompatibility, suggesting their potential as the bone scaffold. CONCLUSIONS Aligned porous CaP ceramic scaffolds with considerably enhanced mechanical properties and tailorable porosity would find very useful applications as the bone scaffold.
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Jung HD, Park HS, Kang MH, Li Y, Kim HE, Koh YH, Estrin Y. Reinforcement of polyetheretherketone polymer with titanium for improved mechanical properties and in vitro
biocompatibility. J Biomed Mater Res B Appl Biomater 2015; 104:141-8. [DOI: 10.1002/jbm.b.33361] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 10/26/2014] [Accepted: 12/09/2014] [Indexed: 11/12/2022]
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Jung HD, Jang TS, Wang L, Kim HE, Koh YH, Song J. Novel strategy for mechanically tunable and bioactive metal implants. Biomaterials 2015; 37:49-61. [DOI: 10.1016/j.biomaterials.2014.10.027] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 10/02/2014] [Indexed: 01/15/2023]
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Lei B, Shin KH, Koh YH, Kim HE. Porous gelatin-siloxane hybrid scaffolds with biomimetic structure and properties for bone tissue regeneration. J Biomed Mater Res B Appl Biomater 2014; 102:1528-36. [PMID: 24596176 DOI: 10.1002/jbm.b.33133] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 01/15/2014] [Accepted: 02/18/2014] [Indexed: 11/05/2022]
Abstract
We produced highly porous gelatin-siloxane (GLA-S) hybrid scaffolds with biomimetic anisotropic porous structure, physiochemical properties, mechanical behaviors and biological functions by treating gelatin-siloxane hybrid gels in an ammonium hydroxide solution. The siloxane used as an inorganic phase could effectively crosslink the gelatin polymer, which allowed for the unidirectional enlargement of ammonia vacuoles during ammonium hydroxide treatment. This created aligned pores in an axial direction when the siloxane contents (10 and 20 wt %) were high. In addition, the gelatin polymer could be uniformly hybridized with the siloxane phase at the molecular level, while intense interaction between these two phases could be achieved. This resulted in a significant increase in mechanical properties. The GLA-S hybrid scaffold with a siloxane content of 10 wt % showed reasonably high compressive yield strength of 4.2 ± 0.1 MPa and compressive modulus of 84 ± 5 MPa at a porosity of 86 vol %, which would be comparable to those of natural cancellous bone. In addition, the GLA-S hybrid scaffold had good biocompatibility assessed by in vitro cell tests using pre-osteoblast MC3T3-E1 cells.
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Jung HD, Yook SW, Han CM, Jang TS, Kim HE, Koh YH, Estrin Y. Highly aligned porous Ti scaffold coated with bone morphogenetic protein-loaded silica/chitosan hybrid for enhanced bone regeneration. J Biomed Mater Res B Appl Biomater 2013; 102:913-21. [DOI: 10.1002/jbm.b.33072] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2013] [Revised: 10/04/2013] [Accepted: 10/20/2013] [Indexed: 11/08/2022]
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Lee JY, Lee JW, Pang KM, Kim HE, Kim SM, Lee JH. Biomechanical evaluation of magnesium-based resorbable metallic screw system in a bilateral sagittal split ramus osteotomy model using three-dimensional finite element analysis. J Oral Maxillofac Surg 2013; 72:402.e1-13. [PMID: 24280169 DOI: 10.1016/j.joms.2013.10.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 10/02/2013] [Accepted: 10/03/2013] [Indexed: 11/30/2022]
Abstract
PURPOSE The aim of this study was to evaluate the stress distribution of a magnesium (Mg)-based resorbable screw system in a bilateral sagittal split ramus osteotomy (BSSO) and to compare its biomechanical stability with those of titanium (Ti)-based and polymer (IN)-based systems. MATERIALS AND METHODS A 3-dimensional BSSO model (10-mm advancement and setback) was constructed with Mimics. Bicortical screw fixation using Ti, IN, and Mg screws was performed with 4 different geometries of fixation. With an occlusal load of 132 N on the lower first molar, the von Mises stress (VMS) distribution was calculated using ANSYS. RESULTS The VMS distribution of Mg was more similar to that of Ti than to that of IN. In all cases, the highest VMS was concentrated on the screw at the most posterior and superior area. Stress was distributed mainly around the screw holes (cancellous bone) and the retromolar area (cortical bone). In the advancement surgery, fixation with 5 Mg screws (5A-Mg, 99.810 MPa at cortical bone) showed biomechanical stability, whereas fixation with the same number of IN screws did not (5A-IN, 109.021 MPa at cortical bone). In the setback surgery, although the maximum VMSs at cortical bone for Mg, IN, and Ti were lower than 108 MPa (yield strength of cortical bone), Mg screws showed more favorable results than IN screws because the maximum VMSs of Mg at cancellous bone were lower than those of IN. CONCLUSION The Mg-based resorbable screw system is a promising alternative to the IN-based system.
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Han CM, Jang TS, Kim HE, Koh YH. Creation of nanoporous TiO2 surface onto polyetheretherketone for effective immobilization and delivery of bone morphogenetic protein. J Biomed Mater Res A 2013; 102:793-800. [PMID: 23589347 DOI: 10.1002/jbm.a.34748] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2013] [Revised: 03/13/2013] [Accepted: 03/20/2013] [Indexed: 01/15/2023]
Abstract
This study evaluated the utility of the creation of a nanoporous TiO2 surface to enhance the in vitro biocompatibility and in vivo osseoconductivity of polyetheretherketone (PEEK) implants by providing favorable sites for the effective immobilization of bone morphogenetic protein-2 (BMP-2). A uniform nanoporous TiO2 layer with a pore diameter of ∼70 nm was successfully created by anodizing a Ti film, which had been deposited onto a PEEK substrate via electron beam (e-beam) evaporation technique. This nanoporous, hydrophilic TiO2 surface enabled the efficient immobilization of BMP-2, resulting in a remarkable enhancement in in vitro biocompatibility that was assessed in terms of cell attachment, proliferation, and differentiation. The in vivo animal tests also confirmed that the nanoporous TiO2 surface immobilized with BMP-2 could significantly enhance the osseoconductivity of PEEK implants. The BMP-immobilized PEEK implant with the nanoporous TiO2 surface showed much higher bone-to-implant contact (BIC) ratio (60%) than the bare PEEK (30%), PEEK with the nanoporous TiO2 surface (50%) and even BMP-immobilized PEEK without the nanoporous TiO2 surface (32%).
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Kim SM, Jo JH, Lee SM, Kang MH, Kim HE, Estrin Y, Lee JH, Lee JW, Koh YH. Hydroxyapatite-coated magnesium implants with improvedin vitroandin vivobiocorrosion, biocompatibility, and bone response. J Biomed Mater Res A 2013; 102:429-41. [DOI: 10.1002/jbm.a.34718] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 03/06/2013] [Accepted: 03/18/2013] [Indexed: 11/07/2022]
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Lei B, Shin KH, Noh DY, Jo IH, Koh YH, Kim HE, Kim SE. Sol–gel derived nanoscale bioactive glass (NBG) particles reinforced poly(ε-caprolactone) composites for bone tissue engineering. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2013; 33:1102-8. [DOI: 10.1016/j.msec.2012.11.039] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2012] [Revised: 11/05/2012] [Accepted: 11/29/2012] [Indexed: 11/27/2022]
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Jun SH, Lee EJ, Jang TS, Kim HE, Jang JH, Koh YH. Bone morphogenic protein-2 (BMP-2) loaded hybrid coating on porous hydroxyapatite scaffolds for bone tissue engineering. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2013; 24:773-782. [PMID: 23344924 DOI: 10.1007/s10856-012-4822-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Accepted: 11/12/2012] [Indexed: 06/01/2023]
Abstract
In this study, a silica xerogel-chitosan hybrid is utilized as a coating material to incorporate bone morphogenic protein-2 (BMP-2) on a porous hydroxyapatite (HA) scaffold for bone tissue engineering. BMP-2 is known as a therapeutic agent for improving bone regeneration and repair. Silica xerogel-chitosan hybrids have been used for the delivery of a growth factor as well as osteoconductive coatings. The biological properties of the hybrid coating incorporated with BMP-2 were evaluated in terms of the BMP-2 release behavior, osteoblastic cellular responses and in vivo performance. BMP-2 was continuously released from the hybrid coating layer on the porous HA scaffold for up to 6 weeks. The hybrid coating containing BMP-2 showed significantly enhanced osteoblastic cell responses in comparison with the hybrid coating and HA substrate. Consequently, new bone formation was significantly increased within the hybrid coating containing BMP-2. These results reveal that the hybrid coating containing BMP-2 has the potential to be used as a bone implant, whose osteogenic properties are promoted by the release of BMP-2 in a controlled manner for a prolonged period of time.
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