Porosity Pattern of 3D Chitosan/Bioactive Glass Tissue Engineering Scaffolds Prepared for Bone Regeneration

Hoda G.H Hammad,Miral Nagy F Salama

doi:10.2174/1874210602115010041

Abstract

Aim: The study was conducted to investigate the obtained external and internal porosity and the pore-interconnectivity of specific fabricated bioactive composite tissue engineering scaffolds for bone regeneration in dental applications. Materials and Methods: In this study, the bioactive glass [M] was elaborated as a quaternary system to be incorporated into the chitosan [C] scaffold preparation on a magnetic stirrer to provide bioactivity and better strength properties for the attempted composite scaffolds [C/ M] of variable compositions. The homogenous chitosan/bioactive glass mix was poured into tailor-made cylindrical molds [10cm×10cm]; a freeze-dryer program was used for the creation of uniform and interconnected macropores for all prepared chitosan-based scaffolds. The morphology of fabricated chitosan [C] and chitosan-bioactive glass [C/ M] composite scaffolds was studied by a scanning electron microscope [SEM] and a mercury porosimeter. In addition, the in-vitro biodegradation rate of all elaborated scaffolds was reported after immersing the prepared scaffolds in a simulated body fluid [SBF] solution. Furthermore, for every prepared scaffold composition, characterization was performed for phase identification, microstructure, porosity, bioactivity, and mechanical properties using an X-ray diffraction analysis [XRD], an X-ray Fourier transfer infrared spectroscopy [FTIR], a mercury porosimetry, a scanning electron microscopy [SEM] coupled to an energy-dispersive X-ray spectrometry [EDS] and a universal testing machine, respectively. Results: All the prepared porous chitosan-based composite materials showed pore sizes suitable for osteoblasts seeding, with relatively larger pore sizes for the C scaffolds. Conclusion: The smart blending of the prepared bioactive glass [M] with the chitosan matrix offered some advantages, such as the formation of an apatite layer for cell adhesion upon the scaffold surfaces, the reasonable decrease in scaffold pore size, and the relative increase in compressive strength that were enhanced by the incorporation of [M]. Therefore, the morphology, microstructure, and mechanical behavior of the elaborated stress loaded biocomposite tissue engineering scaffolds seem highly dependent on their critical contented bioactive glass.

Highlights

IntroductionFor tissue engineering [TE], naturally derived polymers have been proposed and preferred in most variable recent
Four types of chitosan-based scaffolds were prepared by freeze-drying technique [C, 1C:1M, 1C:2M, and 2C:1M], and it had been noted that increasing the bioactive glass [M]
The prepared biocomposite scaffolds were fabricated from chitosan polymer matrix and 46S6 glass [M] [i.e., SiO2 glasses containing Ca and P] in order to achieve successful bone tissue regeneration [36].The scaffolds were prepared by combined bioactivity of both chitosan and 46S6 glass to lead to improvement in the mechanical properties [i.e., compressive strength] of the prepared scaffolds in order to enable them to withstand load application in stress-bearing areas of bone [37]

Summary

Introduction

For tissue engineering [TE], naturally derived polymers have been proposed and preferred in most variable recent. In recent biomedical and clinical applications, the biological and physicochemical properties of chitosan have proven it as an excellent biomaterial for the preparation of drug delivery devices and development in various human tissues such as skin, cartilage, or bone, the processing of chitosan is restricted in tissue engineering applications, as it is usually based on a diluted acetic acid solution [2]. Chitosan has been processed in various forms to be implemented in several tissue engineering purposes, e.g., two-dimensional [2D] membranes [3], nanoparticles [4], three-dimensional [3D] fiber meshes, or polymer fibers [4, 5]. Many preparation methods have been developed for chitosan involving supercritical fluid aided phase inversion technique, freeze-drying process, and lyophilization of chitosan gel solution [9 - 11]

Methods

Results

Discussion

Conclusion