Enhanced Osseointegration of Titanium Alloy Implants with Laser Microgrooved Surfaces and Graphene Oxide Coating

Abstract

Rapid and effective osseointegration, as a critical factor in affecting the success rate of titanium (Ti) implants in orthopedic applications, is significantly affected by their surface microstructure and chemical composition. In this work, surface microgrooved Ti–6Al–4V alloys with graphene oxide coating (Ti–G–GO) were fabricated by a combination of laser processing and chemical assembly techniques. The osteogenic capability in vitro and new bone formation in vivo of the implants were systematically investigated, and biomechanical pull-out tests of the screws were also performed. First, in vitro studies indicated that the optimal microgroove width of the titanium alloy surface was 45 μm (Ti–G), and the optimum GO concentration was 1 mg/mL. Furthermore, the effects of the surface microstructure and GO coating on the in vitro bioactivity were investigated through culturing bone marrow mesenchymal stem cells (BMSCs) on the surface of titanium alloy plates. The results showed that the BMSCs cultured on the Ti–G–GO group exhibited the best adhesion, proliferation, and differentiation, compared with that on the Ti–G and Ti groups. Micro-computed tomography evaluation, histological analysis, and pull-out testing demonstrated that both Ti–G and Ti–G–GO implants had the higher osseointegration than the untreated Ti implant. Moreover, the osteogenic capability of the Ti–G–GO group appeared to be superior to that of the Ti–G group, which could be attributed to the improvement of surface wettability and apatite formation by the GO coatings. These results suggest that the combination of the microgroove structure and GO coatings exhibits considerable potential for enhancing the surface bioactivation of materials, and the combination modification is expected to be used on engineered titanium alloy surfaces to enhance osseointegration for orthopedic applications.

Effect of Chemical Solvents on the Wetting Behavior Over Time of Femtosecond Laser Structured Ti6Al4V Surfaces

“…For such applications, the structuring of surfaces with short pulse laser or, in particular, ultra-short pulse lasers is of special importance in research and industrial applications. Due to the ability of creating stochastic (nano- and/or micro) [ 17 , 18 , 19 ] and highly precise deterministic structures [ 20 , 21 ] it is possible to initiate a desired wetting state in a fast processing time without subsequent processing on metals [ 22 ]. Therefore, the static contact angle (SCA) is often used to characterize the wetting state on laser-structured surfaces and related to relevant structuring parameters and biological response [ 23 , 24 ].…”

Properties improvement of titanium alloys scaffolds in bone tissue engineering: a literature review

“…The coating of punch holes could reduce bone formation. Some compounds containing carbon and phosphorus, such as organic glass, tricalcium phosphate, calcium phosphate, alendronate sodium, carbon graphene, and calcium-silicon compounds, have been shown to exhibit a more substantial osteogenic differentiation promotion effect than the traditional HA coating and have become a particular focus of research (55)(56)(57)(58)(59)(60)(61).…”

Effect of Laser Pulse Overlap and Scanning Line Overlap on Femtosecond Laser-Structured Ti6Al4V Surfaces

“…The topography of implants affects the cellular response and, consequently, the implant performance [1][2][3][4][5][6]. Therefore, the surfaces of titanium, as a widely common material for many biomedical applications, such as dental and orthopedic implants, has been treated in various ways to adjust a proper surface design.…”

“…Sandblasting [7][8][9][10][11], chemical etching [9][10][11], and coatings [10] have been used for roughness modification of titanium surfaces for a long time and have been well investigated. Laser treatment of titanium has been found to be particularly advantageous compared to conventional surface structuring methods because it leads to less contamination of the surfaces [12] and offers the possibility of creating stochastic as well as precise deterministic structures in the microand nanometer range [5,13,14]. In particular, the potential of femtosecond (fs) laser structuring of titanium for use in biomedical implants has been shown in several studies [15][16][17][18].…”