Medical plastics are of great value to the healthcare industry and are used in everything from surgical instrumentation to life-preserving cardiovascular devices. Medical plastics come in a variety of compositions and grades, but what unifies them is that they are safe to use with human tissues. All medical plastics, including high-performance polymers like PEEK, have undergone extensive safety research and testing before they are incorporated into medical components and devices.
PEEK’s uses in medicine are wide-ranging and involve several critical applications. Some of those applications include:
- Interbody fusion cages for spinal fusion procedures
- Orthopedic and arthroscopic applications, for knee and hip components
- Trauma fixation components, which include bone plates and hardware systems
- Cardiovascular devices and components, like tubing, catheter components and defibrillator components
- Dental devices, which include partial removable dentures and dental implants
Within these fields of medicine, PEEK is featured in dozens of components, and its number of uses is growing all the time.
How are medical plastics changing healthcare?
Medical plastics like PEEK bring many advantages to medicine, which is why they are quickly replacing other biomaterials. Here are some of the reasons:
Medical plastics can be sterilized easily –
Hospital-acquired infections (HAIs) are a serious problem, resulting in nearly 100,000 deaths in the U.S. every year. Medical plastics are considered a major weapon in the fight against HAIs, as they can either be disposed of after a single use, or they can be designed with antimicrobial surfaces that resist pathogenic growth. PEEK polymer, for example, can also be sterilized for repeated use via all primary sterilization methods including steam, gamma, and ETO sterilization.
Medical plastics have a strong safety record –
Several plastics are considered biomaterials, which means they are inert when in contact with the body’s tissues. Among plastic biomaterials, PEEK stands out for its long, impressive patient outcome history. PEEK has undergone the rigorous safety testing available for potential biomaterials (including ISO 10993 and USP Class VI), but it also has 20 years of patient reports verifying its biocompatibility.
Medical plastics exhibit excellent material properties –
High-performance polymers like PEEK are especially useful for medical applications because they possess a unique combination of attractive physical properties. PEEK’s flexural modulus, for example, is nearly identical to cortical bone, so it bears weight and stress like bone. This makes it an ideal substitute for native bone in many applications, including spinal fusions. The material will move and support neighboring tissues, and it won’t cause stress shielding in nearby bone that can lead to mineral loss and subsequent bone weakness.
Medical plastics are extremely versatile –
Medical plastics can be converted into components through one of several conversion methods. Those methods include injection molding, machining, extrusion, film calendaring and some even more esoteric methods. With several conversion methods available, device manufacturers have a lot of room in producing the most effective components possible.
Most PEEK medical components are machined, as machining allows for the tightest tolerances, and that’s a priority for any implantable devices. However, medical plastics that aren’t used in vivo, but instead for instruments or equipment, can be converted using injection molding.
How is PEEK being used in medicine?
PEEK is a high-performance polymer, so it possesses a combination of properties that few other materials possess. This gives PEEK a great deal of potential, as it can withstand most any force it might encounter in the human body. As such, here is how medical facilities are making the most of those properties:
- Interbody fusion cages – PEEK’s initial success in medicine was in spinal fusion procedures, where it serves as a frontline material for interbody fusion cages. Interbody fusion cages provide an optimal support for the vertebras to fuse together, so the implant must be safe and it must facilitate osseointegration.PEEK is safe and the newest generation of PEEK cages are designed to optimize bone-in growth, with the use of bone-attracting materials and microporous structures. It’s likely true, then, that PEEK’s status as the first choice in interbody fusion cages is certain.
- Trauma fixation components – PEEK is regularly converted into bone plates and hardware to secure trauma fixation components. PEEK is perfect in this role because it exhibits excellent resilience and pullout strength.
- Cardiovascular tubing and components – PEEK can be extruded into long, uniform segments, which makes it an ideal biomaterial for tubing. PEEK has a low coefficient of friction, so it can be steered through the cardiovascular network without getting stuck or causing harm to arteries or veins.PEEK tubing can be used to deliver a stent or a replacement heart valve. PEEK components are also found in defibrillators and ablation catheters, as it can prevent harmful electrical discharges.
- Arthroscopic and orthopedic components – PEEK’s ability to handle weight and resist wear are impressive, and it’s a suitable biomaterial in hip and knee replacement components, as well as arthroscopic procedures. PEEK can be found in acetabular cups, where its resilience and wear resistance are highly valuable.
- Dental devices – PEEK can function in several roles for dentists, serving as a primary partial denture material, or a dental implant material. PEEK is extremely well-suited for partial dentures, because it can be color matched to nearby tissues, it offers excellent wear resistance and it can be precisely machined to fit a patient perfectly. As a dental implant, PEEK’s bone-like modulus and total biocompatibility make it perfect for interfacing with the jawbone.
Medical plastics, like the versatile and durable PEEK, are found in hundreds of medical devices and instruments. Medical plastics are already achieving a great deal, and with so much research focused on making them even better, the future will continue to focus on plastic and its uses in medicine.