Histological Evaluation Of 3D Printed Porous Structure Soft-tissue Ingrowth

Objective: To study the integration of porous structure and soft-tissue and the characteristics of soft-tissue ingrowth,provide theoretical and data support for clinical application.Methods:1.16 New Zealand White Rabbit of half male and female weighted 2-3 kg with autogenous contrast.In the experimental group,the porous titanium blocks were implanted into the right patellar ligament and rectus femoris of each rabbit.In the contrast group,the solid titanium blocks were implanted into the corresponding part of the left side of the same animal.2.The animals were randomly divided into 4 groups.Respectively at one?three?six and twelve months post implantation,the animals were euthanized by intravenous injection of overdose anesthesia.Then extract the implantation.3.The samples were buried by resin and sliced by hard slicer.Then we observe the ingrowth of the soft-tissue by scanning electron microscope and light microscope with HE and Masson staining,and make qualitative and quantitative analysis by Case Viewer and Image J.Results:During the 18 months' experiment,the operative region were healed very well without severe adverse reactions like infection?ulceration?implant shedding and so on.A total of 29 experimental samples were obtained,in which 14 were implanted into patellar ligament and 15 were implanted into rectus femoris.Two contrast samples were implanted into patellar ligament and rectus femoris.Compact soft-tissue ingrowth was observed in all the experimental samples by scanning electron microscope and light microscope with more than 97% of soft-tissue coverage,which mainly filled by fibrous tissue.There were different contents of neovascularization,fibrous connective tissue and adipose tissue in each sample,with local fibrous capsule formation.The content of fibrous connective tissue in the experimental sample which implanted into patellar ligament with the same implantation time was significantly higher than which implanted into the rectus femoris.Fortunately,the characteristics were observed very stable after long-term(12 months)implantation.The histological observation of the samples in the contrast group showed that there were a large number of fibroblasts around the implant.Conclusions:3D printed porous prosthesis will become a more personalized,stable,firm and biocompatible replacement in the surgical treatment of bone tumor,with tight junction between prosthesis and soft-tissue.Therefore,it can meet the increasing needs of patients for limb function with high-quality effect of soft-tissue reconstruction.