Animal Experimental Study On Shenxiao San To Promote Bone Healing And Porous Scaffold To Promote Osseointegration

The population structure of today's world is gradually aging,which makes the proportion of osteoporosis patients increase year by year.During this period,patients may suffer multiple fractures;if osteoporosis develops to the end stage,bone defects may occur,which may require Implant biomaterials.Aiming at two symptoms caused by osteoporosis,this paper discusses the healing effect of a traditional Chinese medicine poultice on cortical bone fracture and the osseointegration effect of 3D printed titanium alloy prosthesis in cancellous bone.(1)The experimental subjects were New Zealand white rabbits,and the left radius was modeled by surgical fracture.After operation,they were divided into three groups,namely,the non-intervention group,the splint fixation group,and the poultice group.The nanomechanical properties of callus were detected by atomic force microscope and nanoindentation,and the chemical composition of callus was analyzed by Fourier transform infrared spectroscopy(FTIR).Mineral particles and collagen fibers on the surface of the callus could be observed by atomic force microscope,and the collagen structure in the rubbing agent group was much smaller than that in the splint fixation group;the size of bone mineralized particles in the rubbing agent group was 47.5% smaller than that in the splinting group during the same period-69.6%;the callus roughness of the poultice group at 2 weeks after operation was about 69% smaller than that of the splint fixation group,and the callus roughness of the two groups at 6 weeks after operation tended to be similar;The elastic modulus and hardness of the callus in the splint fixation group and the poultice group were measured by nanoindentation.The elastic modulus and hardness of the callus in the two groups were between 2-3GPa and 0.01-0.1GPa,respectively,at 2 weeks.Under the action of poultice,the elastic modulus at 4 weeks after operation was about 27 GPa,which was significantly higher than that in the splint group.The absorbance value of each characteristic band was checked by infrared spectrum.Results The areas of organic matrix amide I(1584-1808 cm-1),carbonate(800-900 cm-1)and hydroxyapatite(886-1218 cm-1)in each group of spectra were calculated by origin2018.The ratios of matrix minerals in the splint immobilization group,Shenxiaosan group for 4 weeks,and Shenxiaosan group for 6 weeks were0.3899,0.5730 and 0.4040,respectively.Through the analysis of the mechanical properties at the nanoscopic level by atomic force microscope scanning and nanoindentation detection,combined with the detection of callus components by spectroscopic detection,it is confirmed that the poultice has a promoting effect on fracture healing.(2)Ten 6-month-old New Zealand white rabbits were selected as experimental objects,and the implants were titanium alloy cancellous bone prostheses with cellular structures fabricated by CAD modeling and 3D printing.The image data was obtained by Micro-CT,and the finite element model was established and solved by software such as Abaqus.The stress and strain data of the region of interest are extracted from the finite element analysis results,and the average stress and strain of the trabecular bone of each model are statistically calculated.The analysis shows that the titanium alloy prosthesis hinders the dispersion and conduction of stress,resulting in the trabecular bone receiving The mechanical stimulation of the scaffold was insufficient,and bone resorption occurred in the scaffold attachment.