3D printed PEEK/HA composites for bone tissue engineering applications: Effect of material formulation on mechanical...

Area of Science:

• Biomaterials Science
• Polymer Science
• Additive Manufacturing

Background:

• Polyetheretherketone (PEEK) is a biocompatible polymer utilized in biomedical applications.
• Enhancing PEEK's bioactivity is crucial for improved integration with bone tissue.
• 3D printing (3DP) offers patient-specific manufacturing but faces challenges with PEEK's high melting point.

Purpose of the Study:

• To develop and characterize 3D printable PEEK composites with enhanced bioactivity.
• To investigate the effect of incorporating pure and doped nano-hydroxyapatite (HA) on PEEK properties.
• To evaluate the in vitro bioactivity and mechanical performance of the fabricated PEEK composites.

Main Methods:

• Production of PEEK-based filaments with 10 wt% nano-HA, Sr-doped nano-HA, and Zn-doped nano-HA via hot-melt extrusion.
• 3D printing of filaments using fused deposition modeling (FDM) after process optimization.
• Characterization including physicochemical, thermal, morphological, and mechanical (tensile) analyses.
• In vitro bioactivity assessment using simulated body fluid (SBF) immersion for 28 days.

Main Results:

• Addition of HA and doped HA increased melting point and decreased crystallization temperature of PEEK without significantly altering crystallinity.
• Mechanical properties showed no significant differences, with a slight reduction in ultimate tensile strength and Young's modulus for PEEK/HA.
• Significant apatite formation was observed on the surfaces of 3D printed PEEK composites containing HA, SrHA, and ZnHA after SBF immersion.

Conclusions:

• Bioactive PEEK composites containing nano-HA, Sr-doped nano-HA, and Zn-doped nano-HA can be successfully fabricated using 3D printing.
• These materials exhibit promising in vitro bioactivity, indicating potential for bone regeneration applications.
• The developed 3DP PEEK composites hold potential for use in craniofacial bone repair and other challenging biomedical implants.