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Additive manufacturing (AM) of polyetheretherketone (PEEK) offers a promising route for producing lightweight, biocompatible, and patient-specific medical implants with complex geometries. This study investigates and optimizes fused deposition modeling (FDM) parameters for fabricating small-scale PEEK medical components with improved dimensional accuracy and surface quality. PEEK’s high processing temperature and thermal contraction make precision printing of fine features challenging. A Taguchi design of experiments (L9 orthogonal array) was employed to assess the effects of nozzle temperature, layer height, printing speed, and extrusion width on dimensional deviation and surface roughness using 5 × 5 × 5 mm cube specimens. Dimensional accuracy was quantified along the horizontal and vertical axes, and surface roughness was measured using a stylus profilometer. Statistical analysis showed layer height was the most significant factor affecting horizontal accuracy (p = 0.0225), while printing speed most strongly influenced vertical deviation. The optimal parameters, 450 °C nozzle temperature, 0.06 mm layer height, 7.5 mm/s printing speed, and 0.4 mm extrusion width, achieved mean deviations of 0.013 mm (horizontal) and 0.049 mm (vertical) with a surface roughness of 4.01 µm. Validation using a benchmark model and micro-computed tomography confirmed improved reproduction of small features under these conditions. The results demonstrate that precise control of FDM parameters enables accurate fabrication of sub-millimeter PEEK structures suitable for medical device applications.
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This content will become publicly available on January 1, 2027
Influence of fused deposition modeling parameters on the mechanical and thermal properties of 3D-printed PEEK dental endosseous implants
Not AvailableObjectives: This study aims to explore the application of Fused Deposition Modeling (FDM) as a 3D printing technique for developing endosseous Polyetheretherketone (PEEK) dental implants. Specifically, the primary aim of the study is to systematically investigate the effects of key FDM processing parameters, including thermal conditions, print speed, layer height, build orientation, and post-processing heat treatments, on the mechanical and thermal properties of PEEK implants. By conducting an in-depth analysis, this study aims to establish optimized processing guidelines for the reliable manufacturing of high-performance, clinically viable PEEK dental implants. Methods: PEEK dental implants were fabricated using FDM with variations in thermal conditions (nozzle, bedplate, and chamber temperatures), print speed, layer height, build orientation, and post-print heat treatments. Mechanical testing (compression and fatigue), detailed thermal characterization using Differential Scanning Calorimetry (DSC), and fractographic analysis were performed. Finite Element Analysis (FEA) was also conducted to understand the implant's load-bearing performance. Results: Nozzle temperature dictates implant resolution, while chamber temperature is a key determinant of implant crystallinity. Interestingly, for PEEK dental implants, all the FDM thermal processing conditions play a crucial role in influencing the part's thermal properties. Moreover, print speed plays an essential role in developing dimensionally accurate high-strength implants. Notably, the fractographic analysis of the failed implants revealed interesting multimodal fracture behavior specific to 3D-printed threaded implants. FEA demonstrates that the implants tend to buckle under load and break at the implant-abutment interface, consistent with experimental results. Furthermore, fatigue testing reveals that PEEK implants, fabricated at a specific build orientation with respect to the bedplate, suffice the Food and Drug Administration durability requirements. Significance: These findings underscore the clinical potential of FDM-developed PEEK as a customizable, lightweight, and durable alternative to conventional metallic implants, paving the way for next-generation patient-specific lightweight dental implant solutions
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- Award ID(s):
- 2152135
- PAR ID:
- 10691226
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Dental Materials
- Volume:
- 42
- Issue:
- 1
- ISSN:
- 0109-5641
- Page Range / eLocation ID:
- 109 to 125
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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