Bone tissue, as the basis and skeleton of the body, which plays an essential role in the functioning of other body organs, requires repair and reconstruction in cases of critical defects. In the meantime, bone tissue engineering as an effective and efficient method in the reconstruction of bone tissue defects and deficiencies has received much attention from researchers. In this branch of tissue engineering science, with the construction and development of three-dimensional porous scaffolds that have the same function as the external matrix of cells, the reconstruction and repair of host tissues is carried out. The 3D printing process has been eva‎luated as an efficient tool with the ability to make complex shapes recently in the development of scaffolds used in body tissue. In this study, polycaprolactone scaffolds and polycaprolactone scaffolds containing 20, 10 and 30% by weight of bredigite were prepared by the 3D printing method of molten deposition modeling. In order to investigate the morphology and identify the phase composition of the studied scaffolds and the synthesized ceramic powder, scanning electron microscope and X-ray diffraction analysis were used, respectively. The results of the scanning electron microscope test showed an increase in the size of the pores and a decrease in the diameter of the scaffolds up to 20% by weight. Also, the images obtained from the analysis of the scanning electron microscope clearly showed the increase in roughness in the samples containing bredigite compared to the pure polycaprolactone sample. The wettability analysis showed an increase in the amount of hydrophilicity and a decrease in the contact angle of the pure polycaprolactone film from 75±4 to 62±2 for the 30% bredigite scaffold by weight. On the other hand, the results of the porosity test confirmed the increase in the percentage of porosity of all scaffolds containing bredigite compared to the pure polycaprolactone scaffold. Based on the mechanical test, adding 20% by weight of bredigite to the polycaprolactone scaffold increased the compressive strength of the polycaprolactone scaffold more than twice (from 8 to 18 MPa) and increased the elastic modulus (from 0.66 to 5.51). The degree of degradability of scaffolds was eva‎luated based on their weight loss in phosphate buffered saline solution during 28 days. The results of the degradation test showed that with the increase in the amount of bredigite, the amount of degradation in polycaprolactone- bredigite scaffolds increases. Also, the increase in the density of the apatite layer on the surface of the scaffolds immersed in the simulated body solution in the 20% by weight sample compared to the pure polycaprolactone sample confirmed the improvement of the biological properties by the bioactive bredigite bioceramic. The MTT test showed the absence of cytotoxicity in pure polycaprolactone and polycaprolactone-20% by weight. The adhesion of MG63 cells on the surface of the scaffold containing 20% by weight of bredigite was much higher than the pure polycaprolactone scaffold. Based on the results obtained in the present study, bredigite polycaprolactone-20% by weight scaffold is suggested for bone tissue engineering applications.

رحمت اله عمادي , رضا مرتضوي

محمد خدائي

عباس بهرامي , مهدي رفيعائي