Most of the leading companies have launched 3D printed Cages platforms. Smaller companies have followed this trend and are developping Titanium 3D implants.The introduction of additive manufacturing into the spinal industry started a revolution enabling increased complexity of implant design and patient-specific solutions. Today, there are more than 30 Lumbar 3D printed cages :http://www.thespinemarketgroup.com/category/3d-ifc/
Understanding 3D Printing Titanium
3D printing titanium is also known as direct metal laser sintering, and it is an additive metal fabrication process that was developed in Germany. This process builds on the basic principles of 3D printing through the application of metallic materials for direct utility in just about any field that would need the uses of such immediately developed technology. So far, the technology has been utilized to create articles of titanium jewelry, as well as mechanical parts for bicycles and other transportation equipment. Currently, the most commonly utilized alloys in the creation process include several different types of stainless steel, as well as cobalt chromium and titanium. However, because of the immediate application of the printing process, just about any type of alloy can be theoretically utilized once it has been developed and validated.
The creation process makes use of a 3D computer model that is uploaded to the printing machine’s software. Usually a technician will have to work with the model on the computer first in order to properly arrange its geometry so that it can be constructed and supported physically as it should be. After the file itself has been finalized and all of the necessary changes have been done to the final draft, the structure in the file is divided into separate layers that are then downloaded to the machine that performs the actual construction operation. This machine is known as the DMLS machine, and it uses a powerful optic laser to perform the construction. The laser fires inside of a special building chamber, and in this chamber, a special platform dispenses the building material over a recoating blade, ensuring that the layer is materialized before the blade moves onward to the next layer. This technology fuses the titanium powder into a solid form through the use of local melting by the focus of the laser beam. Layer by layer, the machine builds the object, usually at twenty micrometers of material utilized per layer. This process can easily allow for very complicated geometric figures to be created from the image. The machine handles all of the work after the technician designs the image, and the process is fully automated, taking just a few hours without any other tooling. The DMLS process is very accurate and can result in detailed objects that possess excellent surface quality and durable properties.
There are numerous benefits that come with utilizing the DMLS over other manufacturing techniques. The most obvious of which is how easily and quickly the object can be produced without any special tooling requirements. Because of the nature of the machine, DMLS process can allow for easier testing procedures on prototypes of machine parts. Titanium is just one of the many materials that can be utilized for various production components. Additionally, DMLS can provide more versatile benefits over traditional production methods. Because of how easily the layers can be arranged and designed, complex internal features can be added to objects that would not have ordinarily been able to contain them. Complicated geometric assemblies can be simplified to a few easy to manufacture parts with the utility of 3D printing titanium. Currently, the technology is being used to manufacture parts that can be directly integrated into several industries, including medical, dental, and aerospace.
What’s So Good About a Titanium 3D Printer Produced Object?
To be considered as a viable manufacturing option, a titanium 3D printer should offer value that goes beyond the current hype surrounding 3D printing. These printers pass this test with flying colors. Here is why 3D printing titanium parts is better than producing them using other manufacturing methods:
1 Greater Complexity and Resolution in Design: DMLS with titanium powder allows greater liberties with the CAD design. This includes deep groves, cooling channels in injection mold, cavities, undercuts and free form surfaces. The minimum wall thickness in DMLS using titanium is 0.3-0.4 mm, allowing incredibly detailed designs to be implemented. The produced parts can also be surface finished in a variety of ways.
2. Excellent Mechanical Properties: Titanium is a strong metal to start with. DMLS does an excellent job of preserving this strength during the manufacturing process. Instead of manufacturing multiple smaller parts before and joining them later, DMLS fuses every parts with the whole structure just as the laser creates it.
3. Accuracy in Production: Each part produced confirms to its sanctioned prototype. Typical achievable part accuracy is around +/- 50 microns.
4. Quick Turnaround Time: Depending on the size, parts can be produced in anywhere between a few hours to a few days. This ensures smooth production of the final product with any bottlenecks where final production is halted by availability of parts.
5. Re-design is Easier: If a part is re-designed, creating the newly tooled part is easy because only the CAD machine drawing of the part needs to be replaced. As such re-designing an existing part doesn’t bear a significant impact on the lead time.
Why are the Leading Companies launching 3D Cages?
- Porous titanium scaffold optimizes bone ingrowth: The most well-known example of porous metal implants are spinal interbodies for interbody fusion. In this technique, the entire intervertebral disc between vertebrae is removed and a titanium device is placed between the vertebra, with or without a bone graft, to maintain spine alignment and disc height. Porous titanium implants are of interest since they exhibit improved strength and lower stiffness compared to the solid metals, and are more aligned with human bone properties. Traditionally, polyetheretherketone (PEEK) interbodies were used for interbody fusion; however, their lack of porous structure presents a disadvantage. By using porous titanium implants, initial fixation of the implant is improved. Additionally, long term stability is ensured due to the ability for bone to grow into the open, interconnected porosities.Additive manufacturing allows to produce porous titanium cages, that combine the biocompatibility of titanium material with improved biomechanical and bone incorporative qualities. The porous titanium scaffold influence the bony fusion process by combining specific macro structural, micro structural and nano structural characteristics.
- Reduce Costs: While durability of the device and improved patient outcomes are most important, cost of production is always an underlying consideration. Significant productivity improvements have been implemented to lower the production costs of porous implants manufactured via DMP. The best example is the cost competitiveness of spinal porous cages produced with selective laser melting, when compared to PEEK volume production of spinal cages and traditional manufactured titanium cages.
- Patient-Specific Solutions: Although this accounts for a small percentage of total medical production, this provides solution to very specific and complex cases.