Orthopedic
Implants
What are Orthopaedic Implants?
We live in a world where an endless number of diseases and infections exist. It is very important to have a means of reprimanding these diseases, as they can be terminal. This is important to return quality of life back to the patient. We often see people around us suffering from damaged bones or deformed body parts. Orthopaedic implants are medical devices or materials used to mend or replace a joint, typically bone, but on rare occasions cartilage tissue, commonly caused by damage to a limb physically during accidents or sports.
Doctors generally use titanium-based implants and insert them into the body to fix the damaged areas. Implants help provide support needed for the duration of healing of broken bones. In case of severe damage, the bone or joint must be removed completely. The implants serve then act as full replacements and need to occasionally be replaced. Leg surgery, bone hip and knee replacements, and elbow joint replacements see the highest number of patients today.
What are Titanium Implants?
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In the past, the materials or metals used for transplants and implants were generally gold or silver. While these were sufficient, they had a lot of downsides, such as high costs, corrosion, and other toxic properties that the metals may possess. Scientists found that Titanium and its alloys can be extremely compatible with the human body. While it can be an expensive investment, Titanium Implants last up to 20 years in the human body. They neither corrode nor oxidise, leading to no internal harm. Titanium is both non-magnetic and non-toxic.
Titanium has contributed a lot to the creation of implants. However, it comes with its own set of shortcomings. Being a metal, it is radiolucent, which means it is opaque to any imaging techniques like MRI or X-rays. This causes difficulties in attempting to ascertain trauma in similar regains post the implant surgery. Also Titanium is much harder than the human bone, so when the two materials are in contact bone is often worn down faster, causing long-term complications for the patient. In the same situation, plastic PEEK performs much better, because it has a hardness that resembles bone more closely.
What are PEEK Implants? Why are they better?
Polyether ether ketone, more commonly known as PEEK, is a semi-crystalline thermoplastic that is well known in the manufacturing industry for its mechanical properties. It is a speciality plastic, requiring temperatures above 500C to print, and is also biocompatible and FDA approved making it useful for implants. It is available in filament form for all FDM/FFF machines and is slowly becoming available in powder form for SLS processes. PEEK is heat and wear-resistant and can substitute some metals due to its weight-to-strength ratio. There are limits on what can be injection moulded but most designs can be injection moulded as long as the components are not excessively complex.
Implants can be 3D Printed in a lab to fit each patient's criteria, and this can lead to a reduction in post-implantation issues. One important aspect for PEEK is how the surface properties are defined to better its use. It can further be modified to induce strong adhesion. It is one of the most ideal solutions to irreplaceable broken bones.
In terms of radiolucency, Titanium, like most metals causes a scattering effect when exposed to X-Rays, MRI or CT Scans, which can make it particularly tricky to plan future surgeries and conduct checkups. PEEK on the other hand presents pure radiolucency which is one of its biggest advantages. And it doesn’t stop there, you can actually manipulate its radiolucency with additives including barium sulfate.