China's second "3D printed titanium interbody fusion device" was approved for market

Additive Manufacturing, also known as 3D printing, uses 3D digital model data as a template to make products by gradually adding raw materials, as opposed to traditional Additive Manufacturing processes. The titanium alloy interbody fusion device, manufactured using Electron Beam Melting EBM additive, features a porous biomimetic bone trabecular structure designed to mimic natural bone and help promote spinal interbody fusion.

Characteristics and advantages of 3D printed titanium interbody fusion apparatus:

1. Macro structure
It has good mechanical strength, corrosion resistance and biocompatibility. By adjusting the size of the micropores, the 3D-printed titanium interbody fusion instrument has an elastic modulus similar to cortical and cancellous bone of the vertebral body. 3D printed titanium alloy interbody fusion device conforms to the anatomical shape of upper and lower endplates between vertebral bodies, which is conducive to full contact with the upper and lower endplates, convenient placement, good initial stability, and no need to worry about the displacement of the fusion device. The surface roughness process provides a micron and nanoscale surface roughness that maximizes the anchoring between bone and implant surfaces, thereby improving bone integration. Studies have shown that surface roughness has beneficial effects on cell differentiation and proliferation.

2. Microstructure
Human cortical bone has a porosity of 5-10%, while cancellous bone has a porosity of 75-90%. Cancellous bone is highly porous, constructed of tightly connected pores ranging from 300 μm to 1000μm in diameter. Current studies suggest that the minimum pore size of bone tissue growth is 100μm, and the critical size of capillary angiogenesis is 300-400μm, and the effect of bone growth is better when the pore size is 300-1000μm. The interconnectivity of pores in porous titanium structure is conducive to bone growth. In vitro studies have shown that human stem cells cultured on similar porous titanium structures have greater osteoblast differentiation ability compared to solid titanium surfaces. This product has a titanium alloy bionic bone trabecular structure, with a designed porosity of 70-80% and an aperture of 300-800um, which can effectively provide channels for bone tissue growth and a surface conducive to cell adhesion, facilitating new bone to grow into the fusion device through micropores and adhere to the metal bone trabecular surface, forming a tight bone-endoplant combination.
3. Excellent visualization
High radiographic visibility enables better contour display, facilitating clear intraoperative and postoperative observation of the fusion apparatus, assessing the contact between the vertebral endplate and the implant, and bone fusion. X-ray implants were clearly visible, CT scans had no scattering, MRI artifacts were reduced, and tantalum markers were not scattered.

4. Clinical application

Good titanium alloy bionic bone trabecular structure design makes the fusion device without bone grafting (no bone grafting window), animal tests and clinical trials show that the product can allow adjacent bone tissue to grow into it freely, and finally achieve bone fusion. The graft-free window design facilitates surgical operation and reduces the possibility of contamination of the fusion apparatus, thereby reducing the chance of surgical infection. The product has complete models and specifications, which can not only meet the needs of cervical and lumbar interbody fusion surgery, but also meet the needs of ALIF, TLIF, OLIF and other surgical methods.