Enhanced Surface Precipitates on Ultrafine-Grained Titanium in Physiological Solution

Abstract

Enhanced cell adherence to the surface of nanocrystallized commercially pure titanium (CP-Ti) was observed by several authors. However, the understanding of the surface modification of Ti in a physiological solution due to nanocrystallized grain size has not been reached. In this work, equal channel angular pressing (ECAP) was applied to manufacturing ultrafine grained CP-Ti. Martensite and Widmanstatten microstructures were also obtained for comparison. The CP-Ti pieces with different microstructures were subjected to soaking tests in a simulated body fluid. Electrochemical impedance spectroscopy (EIS) measurements, X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM), energy dispersive spectrometer (EDS) were used to characterize the surfaces. The results show the surface precipitates mainly contain Ti, O, Ca and P. The quantity of precipitates on ECAPed CP-Ti is the largest among different specimens corresponded to the observation of the thickest layer formation on ECAPed CP-Ti found by EIS. EDS results show more CaPO and less Ti are included on ECAPed Ti comparing to the deposits on other two types of specimens. Smaller numbers of precipitates and denser film are produced on the surface of the water-quenched CP-Ti. The regeneration kinetics of the CaP precipitates evaluated by Gibbs free energy is introduced to interpret the precipitating behaviors on different CP-Ti specimens.

Proliferation of Osteoblasts on Laser-Modified Nanostructured Titanium Surfaces

“…Since that time, many in vitro as well as in vivo studies have investigated the impact of nanostructured surfaces on the behavior of the surrounding cells [ 18 , 19 ]. Zhou et al [ 20 ] suggested one possible explanation, based on changes in the chemical composition of titanium surface immersed in a simulated body fluid (SBF) with an addition of bovine serum albumin (BSA). The higher levels of calcium, phosphorus and oxygen found on the surface of UFG titanium are beneficial to the bioactivity of the titanium implant [ 21 ].…”

Synthesis and Properties of Bulk Nanostructured Metallic Materials

“…A combination of a single ECAP pass followed by cold rolling exhibited a good compromise between mechanical properties and processing efforts, which emphasizes application potential for precursors to UFG microstructures. Zhou et al [2] demonstrated spontaneous modification of the surface of titanium with different substrate microstructures after soaking in a physiological solution. In this research, commercial purity (CP) titanium was processed by ECAP to achieve UFG microstructure and was immersed in simulated body fluid for 60 days.…”

Comprehensive Evaluation of the Properties of Ultrafine to Nanocrystalline Grade 2 Titanium Wires

“…For instance, implants with smaller load-bearing cross-sections are suitable for children [6]. In terms of biocompatibility, pure titanium is associated with increased osteoblast proliferation and better osseointegration [6,7]. Kim and Park [7] established a model explaining enhanced surface cell attachment on nanocrystallized commercially pure titanium (CP–Ti).…”

“…In terms of biocompatibility, pure titanium is associated with increased osteoblast proliferation and better osseointegration [6,7]. Kim and Park [7] established a model explaining enhanced surface cell attachment on nanocrystallized commercially pure titanium (CP–Ti). The reason for this is that the number of nodules at the triple-point junctions of the grain microstructure increases as the grain size is refined through equal-channel angular pressing (ECAP).…”

“…The reason for this is that the number of nodules at the triple-point junctions of the grain microstructure increases as the grain size is refined through equal-channel angular pressing (ECAP). These properties facilitate a connection between the implant and the human tissue [6,7,8,9,10].…”