Comparative Analysis of Wettability and Contact Angle Measurements in 100% PEEK: Assessing Accuracy Across Different Sections- An Invitro Analysis
Abstract
Background and Objective: Polyetheretherketone (PEEK) is highly valued in orthopedic and dental implantology for its biomechanical properties, though its inherent hydrophobicity limits osseointegration. While Fused Deposition Modeling (FDM) enables the fabrication of porous, patient-specific implants, the layer-by-layer extrusion alters surface micro-topography. This in vitro study aimed to comparatively analyze how localized 3D-printed architectural variations—specifically structural beading versus standard lattice struts—affect the dimensional accuracy and regional surface wettability of 100% PEEK constructs.
Materials and Methods: Standardized porous lattice constructs were fabricated from 100% medical-grade PEEK using a high-temperature FDM printer. Optical stereomicroscopy was utilized to evaluate macroscopic dimensional fidelity and microscopic internal porosity across beaded and non-beaded sections. Regional surface wettability was quantified using static water contact angle goniometry across distinct architectural zones.
Results: FDM printing maintained highly consistent internal macroporosity, with pore sizes ranging accurately between 0.389 mm and 0.443 mm without occlusion. However, macroscopic dimensions varied based on localized toolpaths, manifesting as structural beading at the perimeters. Contact angle analysis revealed significant regional disparities in wettability; structurally beaded sections exhibited a contact angle of [Insert Angle]°, compared to [Insert Angle]° for standard planar sections and [Insert Angle]° for internal lattice nodes (p < 0.05).
Conclusion: The surface wettability of 3D-printed 100% PEEK is not uniform; localized print-induced architecture directly dictates regional hydrophobicity. Relying solely on bulk material properties is insufficient for implant design, highlighting the need for targeted post-processing to homogenize surface energy and optimize biological responses.
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