With metal printing beginning to reach a high in the 3D industry and titanium as the up and coming trusty material for manufacturing spanning the gamut from bike frames to spinal implants, the topic is popular, to say the least. But researchers from the University of Waterloo in Ontario have put a new spin on the subject regarding 3D printing processes with metal and layer thicknesses in material as relevant to the ever growing industry of orthopedic applications.
‘On the influence of sintering protocols and layer thickness on the physical and mechanical properties of additive manufactured titanium porous bio-structures,’ authored by Ahmad Basalah, Shahrzad Esmaeili, and Ehsan Toyserkani, outlines their recent study, obviously very important work as it sheds light on how manufacturers can better control the mechanical and physical integrity of 3D printed medical implants. Exactly how they do that can have a direct impact on the condition of the patient after surgery.
As 3D printing and additive manufacturing take a hold in the implant industry, offering the opportunity for customization and personalized care, as well as sometimes greater affordability, the last thing anyone wants to see is issues arising with such new technology, especially in causing a patient to experience pain or discomfort.
The research team, points out however, that aseptic loosening is all too often a concern—where the bond doesn’t hold between an implant and bone—causing patients to be taken back surgery after joint replacements.
The loosening is generally caused by stress shielding, caused lack of lack of bone density—referring back to the insertion of the implant which can essentially sometimes cause the bone to weaken and fall victim to reabsorption. With this in mind, it’s obvious that the creation of a bone implant is a serious process that must involve sophistication and precision.
Popular for many applications due to its strength and reliability, here titanium is used because of its great biocompatibility. As an implant material, it provides higher corrosion resistance than other materials as it offers up a protective oxide layer, which forms on the surface of the implant. To alleviate potential issues with stress shielding, as well as taking advantage of all the other benefits titanium can offer here, the researchers say that the best option is a titanium foam structure, allowing for the proper rigidity and weight.
“Many attempts have been made to mimic cortical bone properties by employing titanium foam,” state the researchers.
Several different studies were performed in consideration to:
Powder compaction level
The variables were then changed to manipulate the porosity and mechanical properties.