Incorporation of Nano-Hydroxyapatite and Chitosan Nanofibers into Polyetheretherketone (PEEK) for Enhanced Bioactive Fixed Prostheses: An In Vitro Study

Background: There is a growing need for prosthetic materials that combine mechanical strength with biological integration.Aim: This in vitro study investigates the synergistic effect of incorporating nano-hydroxyapatite (n-HA) and chitosan nanofibers (ChNF) into poly ether ether ketone (PEEK) to enhance its performance for fixed dental prostheses.Materials and Methods: In the department of Orthodontics at University of Misan College of Dentistry in Iraq, this in vitro experimental study was conducted. PEEK was reinforced with 5 wt.% n-HA and 1 wt.% ChNF using melt blending and compression molding. Flexural strength and surface roughness were evaluated and compared with unmodified PEEK.Results: The reinforced PEEK specimens showed a statistically significant increase in flexural strength (153.4 ± 5.6 MPa vs. 127.8 ± 4.9 MPa, p = 0.002). Surface roughness increased slightly (0.31 ± 0.06 µm vs. 0.23 ± 0.04 µm) but remained within clinically acceptable limits (p = 0.21).Conclusion: Incorporating n-HA and ChNF into PEEK is a promising strategy to improve the mechanical and bio functional properties of prosthetic materials.