Introduction: Polyetheretherketone (PEEK) has emerged as the leading high- performance thermoplastic candidate for replacing metallic implants in the orthopedic industry. Sadly, PEEK implants are commonly manufactured by machining PEEK rods associated with a significant amount of wasted material. Also, it is challenging to manufacture patient-specific implants (PSIs) by conventional machining. Fused Filament Fabrication (FFF) is a sustainable 3D printing modality that can efficiently develop PSIs. However, FFF of high-temperature polymers such as PEEK is challenging as it is difficult to (i) extrude PEEK consistently and (ii) crystallize them homogenously to achieve favorable mechanical properties. Hence, in this study, we analyze the effect of different FFF parameters on the 3D-printed PEEK structures and actual implants and determine a set of optimized FFF parameters that are suitable for developing PEEK-based PSI implants.
Methods: A high-temperature FFF setup FUNMAT HT was used to 3D print the PEEK dental implants. The implant designs were developed based on the CT scans of defects and analyzed in the MicroDicom software. We varied the print speed, layer height and several thermal processing conditions.
Subsequently, mechanical tests were performed by UTM.
Results: We observed that a combination of high nozzle temperatures led to better interlayer adhesion and fusion (Fig 1a). Higher chamber temperature also helped in increasing crystallinity and the load- bearing capacity of the implants. Our comprehensive analyses optimized the set of 3D printing parameters suitable for developing orthopedic implants by the FFF technique. Our results indicate that the combination of Nozzle Temp: 450°C, Bedplate Temp: 150°C, Chamber Temp: 90°C, Layer thickness:
0.1 mm, and Print Speed: 30 mm/sec is optimum for 3D printing design-specific orthopedic implants with high resolution and robust mechanical properties (Fig 1c). In addition, 3D-printed implants can withstand various kinds of physiological forces.
Learning Objectives:
- Upon completion, participants will be able to describe the fundamentals of PEEK printing and utilize the knowledge to successfully 3D print PEEK implants on their own.
- Upon completion, participants will be able to understand the challenges of PEEK printing and learn how to mitigate those challenges.
- Upon completion, participants will be able to demonstrate high-temperature 3D printing to develop PEEK medical devices on their own.
