Osteoconductive Silk Fibroin Binders for Bone Repair in Alveolar Cleft Palate: Fabrication, Structure, Properties, and In Vitro Testing.

Osteoconductive silk fibroin (SF) binders were fabricated for the bone repair of an alveolar cleft defect. Binders were prefigureared by mixing different ratios of a mixture of random coils and SF aggregation with SF fibrils: 100:0 (SFB100), 75:25 (SFB75), 50:50 (SFB50), 25:75 (SFB25), and 0:100 (SFB0). The gelation, molecular organization, structures, topography, and morphology of the binders were characterized and observed. Their physical, mechanical, and biological properties were tested. The SF binders showed gelation via self-assembly of SF aggregation and fibrillation. SFB75, SFB50, and SFB25 had molecular formation via the amide groups and showed more structural stability than SFB100. The morphology of SFB0 demonstrated the largest pore size. SFB0 showed a lowest hydrophilicity. SFB100 showed the highest SF release. SFB25 had the highest maximum load. SFB50 exhibited the lowest elongation at break. Binders with SF fibrils showed more cell viability and higher cell proliferation, ALP activity, calcium deposition, and protein synthesis than without SF fibrils. Finally, the results were deduced: SFB25 demonstrated suitable performance that is promising for the bone repair of an alveolar cleft defect.

Constructed microbubble porous scaffolds of polyvinyl alcohol for subchondral bone formation for osteoarthritis surgery.

Osteoarthritis (OA) is a disease that leads to the damage of subchondral bone. To treat OA, patients can have surgery to implant biomaterials into the damaged area. In this research, biomaterials of 3D porous scaffolds were fabricated by the use of air microbubbles for subchondral bone formation proposed for OA surgery. Microbubbles were generated in a polyvinyl alcohol solution at various air flow rates of 20 (F20), 100 (F100), 200 (F200), and 300 (F300) cc min-1. Molecular organization, structure, and morphology of the scaffolds were characterized and observed by Fourier transform infrared spectroscopy, a differential scanning calorimeter, and a scanning electron microscope, respectively. Physical and mechanical properties based on swelling behavior and compressive strength of the scaffolds were also evaluated. Biological performance by means of osteoblast proliferation, protein synthesis, and alkaline phosphatase activity of the scaffolds were studied. The scaffolds showed molecular organization via interaction of -OH and C = O. They had residual water in their structures. The scaffolds exhibited a morphology of a spherical-like cell shape with small pores and a rough surface produced on each cell. Each cell was well connected with the others. The cell size and porous structure of the scaffolds depended significantly on the flow rate used. The molecular organization, structure, and morphology of the scaffolds had an effect on their physical and mechanical properties and biological performance. F100 was found to be an optimum scaffold offering a molecular organization, structure, morphology, physical and mechanical properties, and biological performance which was suitable for subchondral bone formation. This research deduced that the F100 scaffold is promising for OA surgery.

The bone-mimicking effect of calcium phosphate on composite chitosan scaffolds in maxillofacial bone tissue engineering.

This research explored a new trend in biomaterials science. The bone-mimicking effect of calcium phosphate on chitosan composite scaffolds was evaluated. Chitosan with 2% calcium phosphate was found to have suitable bone-mimicking performance for maxillofacial bone tissue engineering.

Bioactive surface-modified Ti with titania nanotube arrays to design endoprosthesis for maxillofacial surgery: structural formation, morphology, physical properties and osseointegration.

Modification of the surface of titanium into titania (TiO2) nanotube (TNT) arrays was performed by electrochemical anodization to design an endoprosthesis for maxillofacial surgery. TNT arrays with different surface structures were successfully coated on titanium substrates by varying the anodizing voltages and annealed at 450 °C for 4 h. The phase composition and morphology of the nanotubes were examined by x-ray powder diffraction and field-emission scanning electron microscopy, respectively. The biological functions and water wettability of various surface structures were also investigated. The results demonstrated that the annealed nanotubes were composed of an anatase phase only at all applied voltages. The tube diameters and lengths increased as the voltage increased. The surfaces with modification had more wettability, cell adhesion, proliferation, alkaline phosphatase activity and calcium deposition than the surfaces without modification. Finally, the results demonstrated that a modified surface of titanium to produce TNT arrays as a biomaterial is promising to design an osseointegrated surface of endoprosthesis for maxillofacial surgery.

Mimicked scaffolds based on coated silk woven fabric with gelatin and chitosan for soft tissue defect in oral maxillofacial area.

Soft tissue defects in the oral maxillofacial area are critical problems for many patients and, in some cases, patients require an operation coupled with a performance scaffold substitution. In this research, mimicked anatomical scaffolds were constructed using gelatin- and chitosan-coated woven silk fibroin fabric. The morphologies, crystals, and structures were observed and then characterized using scanning electron microscopy, X-ray diffraction, and differential scanning calorimetry, respectively. Physical performance was evaluated from the swelling behavior, mechanical properties, and biodegradation, while the biological performance was tested with fibroblasts and keratinocytes, after which cell proliferation, viability, and histology were evaluated. The results revealed that a coated woven silk fibroin fabric displayed a crystal structure of silk fibroin with amorphous gelatin and chitosan layers. Also, the coated fabrics contained residual water within their structure. The physical performance of the coated woven silk fibroin fabric with gelatin showed suitable swelling behavior and mechanical properties along with acceptable biodegradation for insertion at a defect site. The biological performances including cell proliferation, viability, and histology were suitable for soft tissue reconstruction at the defect sites. Finally, the results demonstrated that mimicked anatomical scaffolds based on a gelatin layer on woven silk fibroin fabric had the functionality that was promising for soft tissue construction in oral maxillofacial defect.

Modified porous scaffolds of silk fibroin with mimicked microenvironment based on decellularized pulp/fibronectin for designed performance biomaterials in maxillofacial bone defect.

Maxillofacial bone defect is a critical problem for many patients. In severe cases, the patients need an operation using a biomaterial replacement. Therefore, to design performance biomaterials is a challenge for materials scientists and maxillofacial surgeons. In this research, porous silk fibroin scaffolds with mimicked microenvironment based on decellularized pulp and fibronectin were created as for bone regeneration. Silk fibroin scaffolds were fabricated by freeze-drying before modification with three different components: decellularized pulp, fibronectin, and decellularized pulp/fibronectin. The morphologies of the modified scaffolds were observed by scanning electron microscopy. Existence of the modifying components in the scaffolds was proved by the increase in weights and from the pore size measurements of the scaffolds. The modified scaffolds were seeded with MG-63 osteoblasts and cultured. Testing of the biofunctionalities included cell viability, cell proliferation, calcium content, alkaline phosphatase activity (ALP), mineralization and histological analysis. The results demonstrated that the modifying components organized themselves into aggregations of a globular structure. They were arranged themselves into clusters of aggregations with a fibril structure in the porous walls of the scaffolds. The results showed that modified scaffolds with a mimicked microenvironment of decellularized pulp/fibronectin were suitable for cell viability since the cells could attach and spread into most of the pores of the scaffold. Furthermore, the scaffolds could induce calcium synthesis, mineralization, and ALP activity. The results indicated that modified silk fibroin scaffolds with a mimicked microenvironment of decellularized pulp/fibronectin hold promise for use in tissue engineering in maxillofacial bone defects. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1624-1636, 2017.

Modified silk fibroin scaffolds with collagen/decellularized pulp for bone tissue engineering in cleft palate: Morphological structures and biofunctionalities.

Cleft palate is a congenital malformation that generates a maxillofacial bone defect around the mouth area. The creation of performance scaffolds for bone tissue engineering in cleft palate is an issue that was proposed in this research. Because of its good biocompatibility, high stability, and non-toxicity, silk fibroin was selected as the scaffold of choice in this research. Silk fibroin scaffolds were prepared by freeze-drying before immerging in a solution of collagen, decellularized pulp, and collagen/decellularized pulp. Then, the immersed scaffolds were freeze-dried. Structural organization in solution was observed by Atomic Force Microscope (AFM). The molecular organization of the solutions and crystal structure of the scaffolds were characterized by Fourier transform infrared (FT-IR) and X-ray diffraction (XRD), respectively. The weight increase of the modified scaffolds and the pore size were determined. The morphology was observed by a scanning electron microscope (SEM). Mechanical properties were tested. Biofunctionalities were considered by seeding osteoblasts in silk fibroin scaffolds before analysis of the cell proliferation, viability, total protein assay, and histological analysis. The results demonstrated that dendrite structure of the fibrils occurred in those solutions. Molecular organization of the components in solution arranged themselves into an irregular structure. The fibrils were deposited in the pores of the modified silk fibroin scaffolds. The modified scaffolds showed a beta-sheet structure. The morphological structure affected the mechanical properties of the silk fibroin scaffolds with and without modification. Following assessment of the biofunctionalities, the modified silk fibroin scaffolds could induce cell proliferation, viability, and total protein particularly in modified silk fibroin with collagen/decellularized pulp. Furthermore, the histological analysis indicated that the cells could adhere in modified silk fibroin scaffolds. Finally, it can be deduced that modified silk fibroin scaffolds with collagen/decellularized pulp had the performance for bone tissue engineering and a promise for cleft palate treatment.