Three-dimensional-printed individualized porous implants: A new “implant-bone” interface fusion concept for large bone defect treatment

Abstract

Bone defect repairs are based on bone graft fusion or replacement. Current large bone defect treatments are inadequate and lack of reliable technology. Therefore, we aimed to investigate a simple technique using three-dimensional (3D)-printed individualized porous implants without any bone grafts, osteoinductive agents, or surface biofunctionalization to treat large bone defects, and systematically study its long-term therapeutic effects and osseointegration characteristics. Twenty-six patients with large bone defects caused by tumor, infection, or trauma received treatment with individualized porous implants; among them, three typical cases underwent a detailed study. Additionally, a large segmental femur defect sheep model was used to study the osseointegration characteristics. Immediate and long-term biomechanical stability was achieved, and the animal study revealed that the bone grew into the pores with gradual remodeling, resulting in a long-term mechanically stable implant-bone complex. Advantages of 3D-printed microporous implants for the repair of bone defects included 1) that the stabilization devices were immediately designed and constructed to achieve early postoperative mobility, and 2) that osseointegration between the host bone and implants was achieved without bone grafting. Our osseointegration method, in which the “implant-bone” interface fusion concept was used instead of “bone-bone” fusion, subverts the traditional idea of osseointegration.

BMP-2 Delivery through Liposomes in Bone Regeneration

“…With the purpose of enhancing the success rate and reducing the osseointegration time, research has focused on improving the interface between the organism and the inorganic substrate by functionalization of the implant with different biolayers and biomolecules. The surface of the implant is the part which interacts with the recipient tissue and for better results we need to fully comprehend all the mechanical, physical, and chemical interactions that take place here [50,51].…”

Extracellular vesicles derived from neural EGFL-Like 1-modified mesenchymal stem cells improve acellular bone regeneration via the miR-25-5p-SMAD2 signaling axis

“…Bone defects can be caused by various clinical diseases and can severely limit rehabilitation [ 1 , 2 ]. However, repairing large bone defects remains a serious challenge [ 1 , 3 ]. Autografts, allografts, xenografts, and other approaches have been used to treat bone defects but clinical challenges such as tissue source, long surgical time, donor site morbidity [ 2 ], risk of disease transmission, and immunoreaction [ 4 , 5 ] have increased significantly.…”

Surface treatment of 3D printed porous Ti6Al4V implants by ultraviolet photofunctionalization for improved osseointegration

“…Globally, over 2.2 million bone graft surgeries are performed annually to reconstruct bone defects in orthopedics, neurosurgery, and dentistry [ 3 ]. A three-dimensional (3D)-printed porous Ti alloy implant was developed and proven to be advantageous in reconstructing bone defects, including accuracy in shape and size with no need for bone grafting, meeting the needs for patient-specific design and immediate stability [ 4 , 5 ]. Further, its porous features favor bone ingrowth [ 6 , 7 ] and avoid stress shielding [ 8 , 9 ] of the solid implant.…”