Development of Multifunctional Materials Based on Poly(ether ether ketone) with Improved Biological Performances for Dental Applications

Abstract

The main target for the future of materials in dentistry aims to develop dental implants that will have optimal integration with the surrounding tissues, while preventing or avoiding bacterial infections. In this project, poly(ether ether ketone) (PEEK), known for its suitable biocompa-tibility and mechanical properties for dental applications, was loaded with 1, 3, and 5 wt.% ZnO nanoparticles to provide antibacterial properties and improve interaction with cells. Sample cha-racterization by X-ray diffraction (XRD), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) as well as mechanical properties showed the presence of the nanoparticles and their effect in PEEK matrices, preserving their relevant properties for dental applications. Al-though, the incorporation of ZnO nanoparticles did not improve the mechanical properties and a slight decrease in the thermal stability of the materials was observed. Hemocompatibility and osteoblasts-like cell viability tests showed improved biological performances when ZnO was present, demonstrating high potential for dental implant applications.

Keywords: dental applications; mechanical pro-perties; poly(ether ether ketone); zinc oxide nanoparticles.

Figure 1

Zinc oxide nanoparticles (a) XRD patterns; (b) SEM micrograph (scale bar: 100 nm); (c) Histogram of ZnO nanoparticles’ diameter distribution.

Figure 2

XRD patterns of ZnO nanoparticles, PEEK, PEEK-ZnO 1%, PEEK-ZnO 3%, and PEEK-ZnO 5%.

Figure 3

Degradation patterns derived from TGA of PEEK, PEEK-ZnO 1 wt.%, PEEK-ZnO 3 wt.%, and PEEK-ZnO 5 wt.%.

Figure 4

Thermal properties of PEEK, PEEK-ZnO 1 wt.%, PEEK-ZnO 3 wt.%, and PEEK-ZnO 5 wt.%.

Figure 5

TEM images of PEEK control (a) and containing (b) 1; (c) 3; and (d) 5 wt.% ZnO nanoparticles.

Figure 6

Mechanical properties of PEEK and PEEK-ZnO composites with different ZnO content. (a) σ vs. ε curves; (b) E; (c) σ_max; (d) ε_break; (e) toughness.

Figure 7

Alamar Blue cell viability assay. (a) p < 0.01 vs. day 1 PEEK and ZnO 1% and p < 0.05 vs. Zn0 3%; (b) p < 0.01 vs. day 1 PEEK; (c) p < 0.001 vs. day 3 PEEK and ZnO 1%; (d) p < 0.001 vs. day 3 PEEK; (e) p < 0.05 vs. day 3 ZnO 1%; (f) p < 0.001 vs. day 6 PEEK and ZnO 1%; (g) p < 0.001 vs. day 6 PEEK; (h) p < 0.05 vs. day 6 ZnO 1%.

Figure 8

Free hemoglobin hemocompatibility assay. (a) p < 0.05 vs. 10′ CTRL Plast; (b) p < 0.001 vs. 10′ CTRL Plast; (c) p < 0.001 vs. 15′ CTRL Plast; (d) p < 0.001 vs. 15′ CTRL Plast and p < 0.05 vs. PEEK 1% ZnO; (e) p < 0.05 vs. 20′ CTRL; (f) p < 0.05 vs. 20′ PEEK, p < 0.01 vs. 3% ZnO and p < 0.001 vs. CTRL Plast; (g) p < 0.001 vs. 40′ CTRL Plast and PEEK.