Biocompatiblity Of Osteoblasts In Titanium Alloy Porous Scaffold

Osteosarcoma,fractures,large bone loss and other diseases have always been the treatment difficulties in clinics.With the development of 3D printing technology,more and more bone implants help clinics solve various difficulties through 3D printing technology.However,there are still some problems in prosthetic replacement,such as the instability of the contact surface between the host bone and the prosthesis implant,mechanical damage,loosening of the prosthesis,stress fracture around the prosthesis and etc.Eventually the prosthetic implant is detached and ectopic,which leads the patient to potential damage.Further enhancing the stability of the prosthetic implant in the host becomes very important.Nowadays,due to the excellent mechanical and material properties,titanium alloy has been widely used in the medical community for implanted prostheses.In this thesis,three kinds of samples with designed apertures of 2.5mm,2.0mm and 1.75 mm are made of titanium alloy Ti-6Al-4V material by 3D printing technology.Firstly,field emission scanning electron microscopy(SEM)and optical microscope are used to characterize the pore size,wire diameter,porosity,mass and volume of the titanium alloy samples.Energy dispersive X-ray spectroscopy showed the contents of titanium,aluminum,and vanadium in the titanium alloy samples.Then,we used mouse osteoblasts MC3T3-E1 as cell model to characterize the biocompatibility of titanium alloy sample.It indicated that osteoblasts adhered to both the outer and inner layers of titanium alloy samples.SEM images showed the surface morphology of osteoblasts grown on titanium alloy samples with different pore sizes,indicating the osteoblasts spread on the different sample surfaces very well.MTT detected the proliferative capacity of cells grown on the samples with three pore sizes at different times,indicating that the proliferation ability of osteoblast increases with the increase of the pore diameter at the same time of culture.However,the proliferative capacity was the strongest for the cells grown in the sample with pore diameter of 2.5 mm.The proliferative ability of the same pore size promoted with the increase of culture time.Alizarin red detected the mineralization ability of osteoblasts grown on titanium alloy samples for three weeks,and the results showed the mineralization capacity gradually increases as the pore size increases.Finite element analysis was performed to investigate the relationship between model deformation and applied load using ABAQUS.When the concentrated force is applied,the displacement increases as the concentration force increases.Fluid dynamics simulation was also studied to investigate the fluid shear force and pressure on both unit model and arrayed model to obtain the fluid shear force and liquid pressure onto the samples using ANSYS FLUENT.Based on the results obtained from this thesis,it showed that osteoblasts can proliferate on three kinds of pore size samples very well,however,the biocompatibility of the samples with a pore size of 2.5 mm was the best.The three-dimensional model designed in this thesis promotes the research of hip replacement surgery or other prosthetic implant surgery.Cell study on titanium alloy prostheses also plays a potential effect onto the biocompatibility experiments of titanium alloy materials in animals.