3D Printed PEKK Structures Shown to Offer Superior Antibacterial Properties for Orthopedic Implants in Comparison Study with PEEK

Connecticut-based Oxford Performance Materials, Inc. (OPM) first commercialized its proprietary OsteoFab process back in 2013; two years later, the company received 510(k) clearance from the FDA for its 3D printed SpineFab VBR System Implants, developed with the OsteoFab platform. The technology uses OPM’s exclusive OXPEKK material – a high performance PEKK (poly-ether-ketone-ketone) polymer formulation, which meets the requirements of both the EU and the FDA for long-term implantable medical device applications.

Now, the company has announced that 3D printed structures made with its PEKK material have better antibacterial properties for orthopedic applications than structures 3D printed using conventional PEEK (poly-ether-ether-ketone).

The OsteoFab process, when combined with OXPEKK, forms a rough, nanostructured surface that can improve bone attachment. This isn’t the company’s first time investigating if PEKK could improve infections, and the results of its independent scientific study, titled “Antibacterial properties of PEKK for orthopedic applications” and published in the International Journal of Nanomedicine, detail the material’s antibacterial benefits when applied in 3D printed OsteoFab structures.

According to the study’s abstract, “In this study, a nanostructured surface was fabricated on poly-ether-ketone-ketone (PEKK), a new orthopedic implant chemistry, comprised of nanopillars with random interpillar spacing. Specifically, after 5 days, when compared to the orthopedic industry standard poly-ether-ether-ketone (PEEK), more than 37% less Staphylococcus epidermidis were found on the PEKK surface. Pseudomonas aeruginosa attachment and growth also decreased 28% after one day of culture, with around a 50% decrease after 5 days of culture when compared to PEEK. Such decreases in bacteria function were achieved without using antibiotics.”

OPM simplified process flow for producing 3D printed implants.

The study states that infections resulting from orthopedic implants have been increasing, while antibiotics developed to kill the bacteria are proving less effective.

“It is clear that new approaches that do not rely on the use of antibiotics are needed to decrease medical device infections,” the researchers write in the study.

3D printed PEKK’s superior antibacterial traits could potentially improve two areas of increasing concern in the medical field, which is why these properties, which apply to OsteoFab devices, will offer, as OPM puts it, “another important layer of differentiation for the performance of OPM medical devices in the marketplace.”

“I am excited that there is another option available for custom facial bony augmentation. The products currently available are porous and have a high incidence of infection when placed through a transoral surgical approach,” Dr. Gregory Chotkowski, Board Certified Oral and Maxillofacial surgeon, said about OsteoFab devices.

“I had the opportunity to use OPM’s 3D printed PEKK mandibular angle implants on several occasions and feel that this material is far superior.  The bacteriostatic properties – combined with custom fabrication – makes this an ideal material for facial augmentation through a transoral approach.”

Scanning electron microscopy images of (A) PEEK, (B) PEKK, and (C) AFM image of PEKK.

In the study, co-authors Mian Wang and Garima Bhardwaj with Northeastern University in Boston and Thomas J. Webster with the Wenzhou Institute of Biomaterials and Engineering, examined samples of 3D printed PEKK, produced using the OsteoFab process, and samples of PEEK, provided by RTI Surgical, which OPM has partnered with before. Among other tests, the resesarchers took contact angle measurements with water to determine the differences between the materials’ wetting abilities, visualized their topographical features under a scanning electron microscope, and collected bacterial cultures.

The results of the study demonstrated the major potential nanostructured PEKK has in terms of anti-infection orthopedic implant applications.

“This study provides convincing results that one may reduce bacteria functions by creating nanorough surfaces on PEKK, and thus nanostructured PEKK should be further studied for a wide range of antibacterial orthopedic applications,” the researchers say in the paper’s conclusion.

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