Porous Biphasic Calcium Phosphate Scaffolds Research Articles

3D gel-printing of hierarchically porous BCP scaffolds for bone tissue engineering

In this study, a conventional technique of porous preparation was used to improve the constructive capability of direct ink writing on microstructures, and the hierarchically porous scaffolds were successfully prepared by 3D gel printing (3DGP). Micron-sized hydroxyapatite (HA) was coated with tricalcium phosphate (TCP) nanopowders synthesized by chemical co-precipitation to form biphasic calcium phosphate (BCP). The random structure of concave micropores was achieved by filling the BCP slurry with PMMA microspheres while successfully controlling the internal porosity of printed filaments. The results showed that the three-stage porous structure was successfully constructed, i.e., macroscopic pores of 1.50-2.00 mm, spherical micropores of 100-200 μm, and inter-powder interstices of 1.00-10.00 μm. Nano-TCP coated micron-HA powders improved the sintering activity of BCP particles. The compressive strength and porosity of the scaffolds sintered at 1400 °C were 2.78 MPa and 84.98%. The hierarchically porous BCP scaffolds had bright applications in bone tissue engineering.

Microstructures and mechanical properties of biphasic calcium phosphate bioceramics fabricated by SLA 3D printing

Porous biphasic calcium phosphate (BCP) bioceramics are considered to be the most promising bone repair materials in clinical medicine. Stereolithography (SLA) 3D printing can precisely fabricate bioceramic scaffolds with complex porous structure. During this process, how to obtain a suitable sintering procedure for BCP bioceramics by SLA 3D printing is the key to determine the microstructures and mechanical properties, but this is absent. In this present study, we prepared BCP bioceramics with superior densification and mechanical properties by SLA 3D printing, and mainly investigated the effects of sintering temperature and condition on the microstructures and mechanical properties of SLA 3D printed BCP bioceramics for the first time. At the optimized procedure of sintering temperature 1250 °C for 2 h, the 3D printed BCP bioceramics showed uniform shrinkage in all directions, and especially the mechanical properties were close to that of human cortical bone. Furthermore, complex porous BCP scaffolds with high porosity (51.49 %) and compressive strength (8.14 MPa) were successfully obtained. BCP bioceramics greatly promoted the proliferation of MC3T3-E1 cells by the release of Ca and P ion and presented excellent bioactivity. This work proves that SLA 3D printing technology can prepare BCP bioceramics with high mechanical and functional properties, and provides a new route for manufacturing high performance BCP bioceramic scaffolds with complex structure by SLA 3D printing for repairing bone defect in clinical.

Biological evaluation of polydopamine and chitosan composite coatings on the 3D printed porous biphasic calcium phosphate scaffold

A current, gradually growing trend is to use bioactive ceramics to develop new bone scaffolds to replace traditional bone implants. Biphasic calcium phosphate (BCP), a mixed material of hydroxyapatite and tricalcium phosphate, has limited osseointegration ability. Therefore, improving the bioactivity and osteoinductive ability of BCP scaffolds through various surface modification methods is an important issue. Polydopamine (PDA) coating, chitosan (CS) coating, and their composite coatings have been previously reported to individually possess a good ability to improve scaffold bioactivity, but few comparisons between them and the optimal coating sequence of PDA and CS have been reported. Herein, we fabricated a BCP scaffold by using a self-made 3D printer, sintered the scaffold, and then prepared PDA, CS, PDA/CS and CS/PDA coatings by solution immersion. Afterwards, the surface morphology, element composition and proportion, compressive strength and surface contact angle of the five groups of scaffolds were characterized. Finally, the adhesion, proliferation and osteogenesis-related gene expression levels of MC3T3-E1 on the five groups in vitro were evaluated in detail. The results showed that the five types of scaffolds were fabricated successfully and that the PDA/CS and CS/PDA coatings had different surface morphologies. The compressive strengths of the composite-coating groups were higher than those of the single-coating groups and the BCP group. The CCK-8 experiment revealed that the composite coatings can promote the initial adhesion and proliferation of cells. The detection results of three osteogenesis-related genes (OCN, COL-1 and Runx-2) proved that the composite coatings had a synergistic effect in promoting osteodifferentiation and that the CS/PDA coating had the greatest effect in improving cell viability and promoting osteogenic differentiation.

Dual-scale porous biphasic calcium phosphate gyroid scaffolds using ceramic suspensions containing polymer microsphere porogen for digital light processing

This study demonstrates a novel type of biphasic calcium phosphate (BCP) gyroid scaffolds featuring of gyroid macroporous structure and micropous BCP walls using poly(methyl methacrylate) (PMMA) microspheres as the porogen for ceramic digital light processing (DLP) technique. To tailor the microporosity of the BCP walls and the overall porosity of the dual-scale porous BCP scaffolds, the PMMA content with regard to the BCP powder was controlled in the range of 40 vol% to 70 vol%. After debinding at 600 °C and sintering at 1200 °C for 3 h, micropores were uniformly created throughout each BCP framework, while preserving 3−dimensional gyroid macroporous structures. As the PMMA content increased from 40 vol% to 70 vol%, the microporosity remarkably increased from 31.9 (±2.5) vol% to 55.2 (±1.4) vol%. This approach allowed the achievement of very high overall porosities (82.2–89.7 vol%) for the dual-scale porous scaffolds. However, all the scaffolds showed reasonable compressive strengths (0.8 MPa −2.1 MPa), which are comparable to those of cancellous bones.

Functionalization of porous BCP scaffold by generating cell-derived extracellular matrix from rat bone marrow stem cells culture for bone tissue engineering.

The potential of decellularized cell-derived extracellular matrix (ECM) deposited on biphasic calcium phosphate (BCP) scaffold for bone tissue engineering was investigated. Rat derived bone marrow mesenchymal stem cells were cultured on porous BCP scaffolds for 3weeks and decellularized with two different methods (freeze-thaw [F/T] or sodium dodecyl sulfate [SDS]). The decellularized ECM deposited scaffolds (dECM-BCP) were characterized through scanning electron microscopy, energy dispersive X-ray spectrometer, and confocal microscopy. The efficiency of decellularization was evaluated by quantifying remaining DNA, sulfated glycosaminoglycans, and collagens. Results revealed that F/T method was more effective procedure for removing cellular components of cultured cells (95.21% DNA reduction) than SDS treatment (92.49%). Although significant loss of collagen was observed after decellularization with both F/T (56.68%) and SDS (70.87%) methods, F/T treated sample showed higher retaining amount of sulfated glycosaminoglycans content (75.64%) than SDS (33.28%). In addition, we investigated the cell biocompatibility and osteogenic effect of dECM-BCP scaffolds using preosteoblasts (MC3T3-E1). Compared to bare BCP scaffolds, dECM-BCP_F/T scaffolds showed improved cell attachment and proliferation based on immunofluorescence staining and water soluble tetrazolium salts assay (p<.001). Moreover, dECM-BCP scaffolds showed increased osteoblastic differentiation of newly seeded preosteoblasts by up-regulating three types of osteoblastic genes (osteopontin, alkaline phosphatase, and bone morphogenic protein-2). This study demonstrated that functionalization of BCP scaffold using cell-derived ECM could be useful for improving the bioactivity of materials and providing suitable microenvironment, especially for osteogenesis. Further study is needed to determine the potential of dECM-BCP scaffold for bone formation and regeneration in vivo.

Fabrication and preliminary biological evaluation of a highly porous biphasic calcium phosphate scaffold with nano-hydroxyapatite surface coating

Considering that the structure of scaffold determines its functionality, in this study biphasic calcium phosphate (BCP) scaffold with highly interconnected macroporous structure was firstly fabricated by a polymeric sponge replication method, in which a ethanol solution (25vol%) was use for preparation of the slurry and a varying slurry viscosity during multiple impregnations was adopted. Then, the surface coating consisting of nano-hydroxyapatite (nHA) particles was formed by a dip coating technology, i.e. immersing the porous scaffold into the nHA slurry (20mg/mL) and sintering it at 650°C. Preliminary in vitro experiments showed that compared to BCP one, nHA-coated BCP scaffold could increase protein adsorption, form more complex bone-like apatite, and promote cell adhesion and proliferation, indicating that nHA-coated BCP scaffold exhibited superior biocompatibility and bioactivity. It might be attributed to its surface nanostructure and abundant nano- to micro- scale pores (< 10µm). This nHA-coated BCP scaffold with both trabecular framework and surface nanoscale topography holds great promise in serving as bone graft for the orthopedic application.

Effects of Collagen Grafting on Cell Behaviors in BCP Scaffold with Interconnected Pore Structure

BackgroundThis study was to investigate the effect of collagen grafted porous biphasic calcium phosphate (BCP) on cell attachment, proliferation, and differentiation. Porous BCP scaffolds with interconnected micropore structure were prepared with were prepared and then grafted with a collagen type I. The hydroxyapatite (HA) and β-tricalcium phosphate (TCP) ratio of the TCP scaffolds was about 60/40 and the collagen was crosslinked on the TCP scaffold surface (collagen-TCP).ResultsThe sintered BCP scaffolds showed fully interconnected micropore structures with submicron-sized grains. The collagen crosslinking in the scaffolds was conducted using the the N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride and N-hydroxysuccinimide (NHS) crosslinking method. The cell proliferation of collagen-BCP scaffolds showed a similar result to that of the BCP scaffolds. However, osteoblastic differentiation and cell attachment increased in the collagen-BCP scaffolds.ConclusionsCollagen-BCP scaffold improved the cell attachment ability in early phase and osteoblastic differentiation.

Characterization of human periodontal ligament cells cultured on three-dimensional biphasic calcium phosphate scaffolds in the presence and absence of L-ascorbic acid, dexamethasone and β-glycerophosphate in vitro.

The aim of this study was to evaluate the effect of porous biphasic calcium phosphate (BCP) scaffolds on the proliferation and osteoblastic differentiation of human periodontal ligament cells (hPDLCs) in the presence and absence of osteogenic inducer (L-ascorbic acid, dexamethasone and β-glycerophosphate). The cell growth within the scaffolds in the absence of osteogenic inducers was studied by cell counting kit-8 (CCK-8) assay and scanning electron microscopy (SEM). Alkaline phosphatase (ALP) activity and osteoblastic differentiation markers of hPDLCs in BCP scaffolds were examined in the presence and absence of osteogenic inducers. The cell number of hPDLCs in the BCP scaffolds was less than that of hPDLCs cultured in microplates (control). SEM images showed that cells successfully adhered to the BCP scaffolds and spread amongst the pores; they also produced abundant extracellular cell matrix. In the presence and absence of osteogenic inducers, the ALP activity of hPDLCs within BCP scaffolds was suppressed in varying degrees at all time-points. In the absence of osteogenic inducers, hPDLCs in BCP scaffolds express significant higher levels of osteopontin (OPN) mRNA than the control, and there were no significant differences for Runx2 and osteocalcin (OCN) mRNA levels compared with those cultured in microplates. In the presence of osteogenic inducers, Runx2 expression levels were significantly higher than those in control. OPN and OCN mRNA levels were downregulated slightly. Three-dimensional porous BCP scaffolds are able to stimulate the osteoblastic differentiation of hPDLCs in the presence and absence of osteogenic inducer and may be capable of supporting hPDLC-mediated bone formation.

Macroporous biphasic calcium phosphate scaffolds reinforced by poly-L-lactic acid/hydroxyapatite nanocomposite coatings for bone regeneration

Three-dimensional (3D) interconnected porous scaffolds with biomimetic hierarchical architectures and mechanical characteristics are critical for the success of bone regeneration. In this paper, biphasic calcium phosphate (BCP) scaffolds were coated with medical-grade poly-L-lactic acid/hydroxyapatite (mPLLA/HA) nanocomposites to create controlled surface roughness while remaining the interconnected porous structures. Such mPLLA/HA coatings substantially improved the compressive strength of the scaffolds to 3.17–3.95MPa, in contrast to 0.31MPa for the as-prepared bare porous BCP scaffolds. Moreover, these mPLLA/HA-coated porous scaffolds were demonstrated to provide excellent support to the growth and proliferation of human barrow mysenchymal stem cells (hBMSCs). The hBMSCs-seeded mPLLA/HA-coated scaffolds were implanted to large necrotic lesions in the rabbit femoral head. New bone tissues were observed after two months, followed by gradient new bone formation over months according to H&E and Masson staining analysis. These results suggest that the mPLLA/HA-coated BCP scaffolds with improved mechanical strength and osteogenesis may be applied for bone regeneration.

In vitro biodegradable and mechanical performance of biphasic calcium phosphate porous scaffolds with unidirectional macro-pore structure

In this study, porous biphasic calcium phosphate (BCP) scaffolds were fabricated by a freeze–gel casting technique using a tertiary-butyl alcohol (TBA) based slurry. After sintering, unidirectional macropore channels of scaffolds aligned regularly along the TBA ice growth direction were tailored simultaneously with micropores formed in the outer wall of the pore channels. The synthesized porous BCP scaffolds (two different sintering temperatures) exhibit compressive strength of 46.8MPa for 43.0% porosity and 33.1MPa for 45.9% porosity, respectively. After immersion in Hank's balanced salt solution (HBSS) for 1, 2, 4, 8 weeks, a precipitation started to be formed with individual small granules on the scaffolds surface. In the case of BCP scaffolds sintered at 1200°C, β-TCP were slowly degraded with increasing the immersing time; on the other hand, α-TCP (from BCP scaffolds sintered at 1300°C) was extremely degraded within 1 week of immersing. This behavior could be due to a fast hydrolysis (dissolution–reprecipitation) as a phase transformation from α-TCP to brushite or apatite compared to the β-TCP. After immersion in HBSS, overall the compressive strength of the scaffolds reduced by the gradual degradation in biological environment solution. This behavior is consistent with the degradation behavior of scaffolds after immersion in HBSS.

Fabrication and Characterization of Porous Biphasic Calcium Phosphate Scaffolds by Doping TiO&lt;sub&gt;2&lt;/sub&gt;

This study aims to improve the strength of porous BCP samples by the addition of titanium dioxide (TiO2), the well known biocompatible and strong ceramic. BCP powder with HA/TCP ratio of 70/30 (BCP7030) obtained by mixing a pure HA and β-TCP powder. TiO2 powder with 2 (BCP_2Ti), 5 (BCP_5Ti) and 10 (BCP_10Ti) %wt were added into the BCP7030 powder, then ball milled in ethanol for 6 hrs. The porous samples were fabricated by the combination of the gel-casting and freeze drying techniques. All samples were sintered at 1100°C for 2 hrs. X-ray diffractometry (XRD) and scanning electron microscopy (SEM) were used to determine crystal structures and morphology of the sintered samples, respectively. Mechanical properties and porosity of samples were measured by using the universal testing machine and Archimedess principle, respectively. XRD results showed that the phases of the undoped sample can be indexed HA and β-TCP with the ratio of 70/30 as the major phases. In BCP_2Ti, CaTiO3 was observed as a minor phase among the crystallization of HA and β-TCP with the proportion of 30:70. Meanwhile, in BCP_5Ti and BCP_10Ti, XRD patterns revealed a completely transformation of HA to β-TCP with minor phases of CaTiO3 and TiO2. The microstructure of sintered samples present highly porous structure which consisted of two-dimensional pore channels along the long axis and the short axis, which replicates the ice and pore orientation in the direction of freezing. Relatively, the porosity of the samples was increased with the amount of TiO2. Surprisingly, an additions of the TiO2 was not rather improved the mechanical strength of porous BCP7030 in this study. This might be a result of a high percentage of porosity (84%).

동결-젤 주조 공정 기반 삼차부틸알코올을 이용한 단일방향 기공구조를 가지는 이상인산칼슘 세라믹 지지체의 제조 및 특성평가

Porous biphasic calcium phosphate scaffolds were fabricated by a freeze-gel casting technique using a tertiary-butyl alcohol (TBA)-based slurry. After sintering, unidirectional macropore channels of scaffolds aligned regularly along the TBA ice growth direction were tailored simultaneously with micropores formed in the outer wall of the pore channels. The crystallinity, micro structure, pore configuration, bulk density, and compressive strength for the scaffolds were investigated with X-ray diffractometery, scanning electron microscopy analysis, a water immersion method, and a universal test machine. The results revealed that the sintered porosity and pore size generally resulted in a high solid loading which resulted in low porosity and small pore size, which relatively increased the higher compressive strength. After being sintered at 1100-1300℃, the scaffolds showed an average porosity and compressive strength in the range 35.1-74.9% and 65.1-3.0 MPa, respectively, according to the processing conditions.

Enhanced sintering ability of biphasic calcium phosphate by polymers used for bone scaffold fabrication

Biphasic calcium phosphate (BCP), which is composed of hydroxyapatite [HAP, Ca10(PO4)6(OH)2] and β-tricalcium phosphate [β-TCP, β-Ca3(PO4)2], is usually difficult to densify into a solid state with selective laser sintering (SLS) due to the short sintering time. In this study, the sintering ability of BCP ceramics was significantly improved by adding a small amount of polymers, by which a liquid phase was introduced during the sintering process. The effects of the polymer content, laser power and HAP/β-TCP ratios on the microstructure, chemical composition and mechanical properties of the BCP scaffolds were investigated. The results showed that the BCP scaffolds became increasingly more compact with the increase of the poly(l-lactic acid) (PLLA) content (0–1wt.%) and laser power (6–10W). The fracture toughness and micro-hardness of the sintered scaffolds were also improved. Moreover, PLLA could be gradually decomposed in the late sintering stages and eliminated from the final BCP scaffolds if the PLLA content was below a certain value (approximately 1wt.% in this case). The added PLLA could not be completely eliminated when its content was further increased to 1.5wt.% or higher because an unexpected carbon phase was detected in the sintered scaffolds. Furthermore, many pores were observed due to the removal of PLLA. Micro-cracks and micro-pores occurred when the laser power was too high (12W). These defects resulted in a deterioration of the mechanical properties. The hardness and fracture toughness reached maximum values of 490.3±10HV and 1.72±0.10MPam1/2, respectively, with a PLLA content of approximately 1wt.% and laser power of approximately 10W. Poly(l-lactic-co-glycolic acid) (PLGA) showed similar effects on the sintering process of BCP ceramics. Rectangular, porous BCP scaffolds were fabricated based on the optimum values of the polymer content and laser power. This work may provide an experimental basis for improving the mechanical properties of BCP bone scaffolds fabricated with SLS.

Hydroxyapatite/poly-l-lactide nanocomposites coating improves the adherence and proliferation of human bone mesenchymal stem cells on porous biphasic calcium phosphate scaffolds

A well-developed three-dimensional (3-D) biphasic calcium phosphate (BCP) scaffold with interconnectivity and high porosity was fabricated for bone tissue engineering. After being coated with hydroxyapatite/poly-l-lactide (HA/PLLA) nanocomposites, the scaffold maintained the framework structure, and the porous network structure of scaffolds remained unchanged. MTT assay showed significantly increased proliferation of human bone mesenchymal stem cells (hBMSCs) on coated BCP scaffolds compared with uncoated scaffolds 5 days after seeding (p<0.05). Under scanning electron microscopy, hBMSCs on the coated BCP scaffolds showed more spreading on the first day after seeding. Furthermore, flocculent mineral accretions were formed on the surface of HA/PLLA coating. Cell adherence and proliferation ability of hBMSCs on scaffolds were improved by coating with HA/PLLA nanocomposites.

Gas foaming fabrication of porous biphasic calcium phosphate for bone regeneration

For reconstruction of bone defects resulting from the treatment of bone fractures or tumors or for the reconstruction of bone tissues following the surgery of organs or the like, biomaterials, including metals, polymers and ceramics, have been used. In this study, among ceramic materials, biphasic calcium phosphate (BCP) consisting of hydroxyapatite having excellent bioactivity and osteoconductivity, and β-tricalcium phosphate having high biodegradability, were mixed at a ratio of 60:40, which is suitable for new bone formation. To manufacture porous BCP scaffold, which has interconnected pores and is suitable for tissue regeneration and reconstruction, a polyurethane foaming (gas foaming) fabrication was applied to manufacture a bone scaffold satisfying various functional requirements. As the results, bone scaffolds having a pore size ranging from 300 μm to 800 μm and a porosity ranging from 75% to 85% could be manufactured using this process. In in vitro and in vivo animal tests, it was confirmed that the scaffold manufactured in this study can be effectively used as a bone scaffold, which is biocompatible and has the ability to induce bone differentiation and regeneration.

Porous Biphasic Calcium Phosphate Scaffolds from Cuttlefish Bone

Cuttlefish bone is an inexpensive, readily available, morphologically complex natural material. It has an open structure, consisting of layers separated by pillar-like structures made of calcium carbonate. In this study natural bones from cuttlefish were successfully converted into porous biphasic calcium phosphate (BCP) scaffolds with a range of hydroxyapatite and β-tricalcium phosphate compositions. The process involved reaction with solutions of phosphoric acid (H3PO4) and 2-propanol, followed by heat treatment at high temperatures (up to 1300°C) in air. The crystalline composition of the BCP scaffolds could be controlled by varying the concentration of the H3PO4 in solution, and the duration of reaction time at room temperature. The original microstructure of the cuttlefish bone was preserved in the BCP scaffolds which featured >90% interconnected porosity. The structure consisted of continuous macroporous channels with smallest measured cross-sectional openings of 400 μm × 100 μm size. The BCP scaffolds prepared with 16 wt% H3PO4 solution had a measured compressive strength of 2.38 ± 0.24 MPa, with a characteristic noncatastrophic failure behavior. The ability to tailor the composition of these BCP scaffolds allows development of implants with controlled biodegradation, while their superior mechanical and microstructural properties stand to benefit efficient osteointegration and osteoinduction.

Synthesis and characterization of porous biphasic calcium phosphate scaffold from different porogens for possible bone tissue engineering applications

By using the wet precipitation method, Biphasic calcium phosphate granules were synthesized with Ca/P ratio1.52 and controlled porosity, pore size distribution, and granule size. Microporosity was then obtained by adjusting sintering temperature while macroporosity was prepared by adding 1:3 wt% ratio of two normally used porogens (naphthalene and sugar) and 2 newly introduced porogens (sago and lentil). Samples from each ratio were pressed into pellets and were fired at 500?C for 2 hours with 0.5?C/minute heating rate (for removal of porogens) and further sintered at 850?C for 2 hours with 5?C/minute before cooling down to room temperature. The granules were prepared by crushing and sieving BCP sintered pellets to get granules of sizes ranging from 250-500?m. X-rays diffraction (XRD), field emission scanning electron microscope (FESEM), particle size and porosity analyses were employed in order to characterize the granules. A round to oval shape pores with 200-400 ?m size were obtained and identical to the prepared porogens? particle size. This approach gives the desirable properties near to normal bone leading to a perfect osteogenesis for the purpose tissue engineering.

Fabrication and Characterization of Ag-coated BCP Scaffold Derived from Sponge Replica Process

As a starting material, BCP (biphasic calcium phosphate) nano powder was synthesized by a hydrothermal microwave-assisted process. A highly porous BCP scaffold was fabricated by the sponge replica method using 60 ppi (pore per inch) of polyurethane sponge. The BCP scaffold had interconnected pores ranging from to , which were similar to natural cancellous bone. To realize the antibacterial property, a microwave-assisted nano Ag spot coating process was used. The morphology and distribution of nano Ag particles were different depending on the coating conditions, such as concentration of the solution, microwave irradiation times, etc. With an increased microwave irradiation time, the amount of coated nano Ag particles increased. The surface of the BCP scaffold was totally covered with nano Ag particles homogeneously at 20 seconds of microwave irradiation time when 0.6 g of was used. With an increased amount of and irradiation time, the size of the coated particles increased. Antibacterial activities of the solution extracted from the Ag-coated BCP scaffold were examined against gram-negative (Escherichia coli) and gram-positive bacteria (Staphylococcus aureus). When 0.6 g of was used for coating the Ag-coated scaffold, it showed higher antibacterial activities than that of the Ag-coated scaffold using 0.8 g of .

Fully Interconnected Globular Porous Biphasic Calcium Phosphate Ceramic Scaffold Facilitates Osteogenic Repair

An appropriate scaffold, which provides structural support for transplanted cells and acts as a vehicle for the delivery of biologically active molecules, is critical for tissue engineering. We developed a fully interconnected globular porous biphasic calcium phosphate ceramic scaffold by adopting a foaming method, and evaluated its efficiency as a bone substitute and a scaffold for bone tissue engineering by in vitro and in vivo biocompatible analysis and its osteogenic healing capacity in rat tibial bone defects. They have spherical pores averaging 400um in diameter and interconnecting interpores averaging 70um in diameter with average 85% porosity. They elicited no cytotoxicity and noxious effect on cellular proliferation and osteoblastic differentiation during the cell-scaffold construct formation. Also the bone defects grafted with fully interconnected globular porous biphasic calcium phosphate ceramic blocks revealed excellent bone healing within 3 weeks. These findings suggest that the fully interconnected porous biphasic calcium phosphate scaffold formed by the foaming method can be a promising bone substitute and a scaffold for bone tissue engineering.