Development of β Type Ti23Mo-45S5 Bioglass Nanocomposites for Dental Applications

Abstract

Titanium β-type alloys attract attention as biomaterials for dental applications. The aim of this work was the synthesis of nanostructured β type Ti23Mo-x wt % 45S5 Bioglass (x = 0, 3 and 10) composites by mechanical alloying and powder metallurgy methods and their characterization. The crystallization of the amorphous material upon annealing led to the formation of a nanostructured β type Ti23Mo alloy with a grain size of approximately 40 nm. With the increase of the 45S5 Bioglass contents in Ti23Mo, nanocomposite increase of the α-phase is noticeable. The electrochemical treatment in phosphoric acid electrolyte resulted in a porous surface, followed by bioactive ceramic Ca-P deposition. Corrosion resistance potentiodynamic testing in Ringer solution at 37 °C showed a positive effect of porosity and Ca-P deposition on nanostructured Ti23Mo 3 wt % 45S5 Bioglass nanocomposite. The contact angles of glycerol on the nanostructured Ti23Mo alloy were determined and show visible decrease for bulk Ti23Mo 3 wt % 45S5 Bioglass and etched Ti23Mo 3 wt % 45S5 Bioglass nanocomposites. In vitro tests culture of normal human osteoblast cells showed very good cell proliferation, colonization, and multilayering. The present study demonstrated that porous Ti23Mo 3 wt % 45S5 Bioglass nanocomposite is a promising biomaterial for bone tissue engineering.

Keywords: 45S5 bioglass; etching; nanocomposite; powder metallurgy; surface properties; titanium.

Figure 1

Experimental setup Ti23Mo-x wt % 45S5 Bioglass nanocomposite synthesis and electrochemical treatment procedure.

Figure 2

X-ray diffraction spectra of Ti (a); Mo (b) and 45S5 Bioglass (c) powders, their mixture after 30 h of mechanical alloying (d); and after annealing at 800 °C for 0.5 h: Ti23Mo (e); Ti23Mo 3BG (f); Ti23Mo 10BG (g).

Figure 3

Scanning electron microscopy (SEM) micrographs of Ti23Mo alloy (a); Ti23Mo 3BG (b) and Ti23Mo 10BG nanocomposites (c); Energy dispersive spectroscopy (EDS) analysis of the surface of sintered Ti23Mo 3BG nanocomposite is shown in (d).

Figure 4

SEM micrographs of Ti23Mo 3BG after anodic oxidation (a) and additional Ca-P deposition (b) with EDS spectrum (c).

Figure 5

X-ray diffraction (XRD) spectra of Ti23Mo 3BG nanocomposite before (a) and after the surface biofunctionalization (b,c); etched (b) and Ca-P deposited (c).

Figure 6

Potentiodynamic polarization curves of microcrystalline Ti (a); Ti23Mo 3BG nanocomposites before (b) and after electrochemical etching (c) as well as after additional Ca-P deposition (d) in Ringer’s solution at 37 °C.

Figure 7

Optical profiler 3D topography of the Ti23Mo 3BG nanocomposites before (a) and after electrochemical etching with additional Ca-P deposition (b); 0.9 mm × 1.2 mm scan size.

Figure 8

Optical profiler surface scans and X-profiles of the Ti23Mo 3BG nanocomposites before (a) and after electrochemical etching (b) as well as after additional Ca-P deposition (c).

Figure 9

Contact angles of glycerol on the nanostructured bulk Ti23Mo alloy (a) and Ti23Mo 3BG nanocomposite before (b) and after electrochemical etching (1 M H₃PO₄ + 2% HF; 10 V/30 min) (c) as well as after additional Ca-P deposition (d).

Figure 10

Osteoblast culture on the surface of the Ti23Mo 3BG nanocomposite before etching (a,b,c), after etching (d,e,f) and after etching with additional Ca-P deposition (g,h,i) after 1st (a,d,g) and 5th day ((b,c), (e,f) and (h,i)—different magnifications).