Tag Archives: PPSU

Plastics for Medical Device Applications, Where’s the Innovation?

I began working with Orthopedic medical device manufacturers in the late 90’s .  Back then we had the typical materials for the Orthopedic industry. Those included PPSU, PEI, PP, PE, POM-C and of course UHMW. The applications utilizing these materials were all pretty much the same: provisional trials for knees hips and shoulders, instrumentation handles, impactors, bearings and implants amongst other applications. In many industries we hear about new materials being developed on a regular basis, but in medical it almost seems time is standing still. Where’s the innovation for medical device applications?

Polymer Technologies for Medical Remain Virtually Unchanged

Not a lot has changed over the years on the Polymer side to really catapult plastics into a place up there with the Ti Eli’s and CoCr of their alloy counterparts.  Sure, we’ve seen a nice niche’ for Heat Stabilized Polypropylene used in Surgical Caddies and some filled materials primarily BaSO4 used in PPSU and PEI, so they are radio opaque and are visible under X-Ray. We’ve also seen some of the carbon fiber composites with a PAEK base adopted in a variety of roles from targeting guides to external fixation devices.

Let’s not forget about PEEK either, which has played a significant role in medical devices for the past 15 years.  Unfortunately the majority of the applications for that material are for implants.  Although there have been a variety of other applications using PEEK that are not of the implantable variety,  utilizing PEEK that is approved for 24 hour direct contact with the body has only begun to flourish over the last few years.  PEEK Classix which is approved for human implant up to 30 days has also seen a dramatic rise in popularity not only in Orthopedic, Spine and Trauma applications but dental applications as well.  But Implant Grade PEEK per ASTM  F2026 has really been the most popular of all of the medically approved PEEK variations with spinal cages being far and away the biggest reason for that.

The current state of medical plastics innovations leads to many questions. When is the next generation of FDA approved (Cl. VI/ ISO:10993) polymers going to debut? What will those breakthrough materials be?

Why has it been so long since we have seen innovations in polymer materials for medical use?
– Is it because of the fear of the liability risk?
– Is all the requisite testing that is involved in bringing that kind of innovative polymer to market holding up efforts?
– Have scientists not yet developed a material  that can compete in price and performance to a PEEK or PPSU?
– Will the next generation of polymer be a quantum leap supplanting current materials that have been mainstays in the market like a PPSU?
– Will it offer not only compressive and tensile strengths to compete with our alloy counterparts but the elastic modulus and lightweight performance that the market demands?  I for one, am hopeful that will be the case.

On Another Related Note, Let’s Talk About how the FDA may Be Impacting the Development of Materials for Medical Applications

In July/August of 2012 the FDA submitted new guidance for “Acceptance and Filing Reviews of Pre-Market Approval (PMA) Acceptance” for Medical Devices and in Dec 2012 / January2013 this new guidance was implemented.  With the new guidance the FDA has put greater emphasis on qualifying that all materials are safe and effective in the way they are used in the application. Plastics being a major component used in many surgical procedures are now required to be fully qualified where they may not have been in the past.   Some of the main concerns of plastics being used is not necessarily what the chemical composition or molecular chain is, but rather, what exactly is in them?  We know that PPSU is used in medical procedures and can have direct body contact of bone, blood and tissue .  The real question beyond that is what makes that material blue, brown or green?
– Are the compounds that turn that naturally amber PPSU blue,  safe and effective?
– Does that material meet the FDA requirements for percentages by weight and have those specific compounds and percentages been tested to show they are safe for the general public?
The onus of proving these things out  does not fall in the laps of the FDA it falls in the laps of the device manufacturers, the material suppliers, the shapes producers and the resin manufacturers.   The device market has good reason to be concerned as well.  They want to ensure they are putting out safe, reliable and effective products.  The last thing they need is a product recall or worse a class action lawsuit. We know that plastics provide many benefits including lighter weight, wear resistance, chemical resistance and more and as I see developments in other industries I look toward the future of new plastics for medical devices with great hope and I hope you will too.

Dave Piperi

Sales and Marketing Manager
Medical Materials
ThyssenKruppMaterials NA
AIN Plastics Division

To learn more about AIN Plastics and our materials for medical applications please visit our website or contact our Medical Technologies Group toll free: 877.770.6337.

email: david.piperi@thyssenkrupp.com