Improved Corrosion Behavior and Biocompatibility of Porous Titanium Samples Coated with Bioactive Chitosan-Based Nanocomposites

Abstract

Porous titanium implants can be a good solution to solve the stress shielding phenomenon. However, the presence of pores compromises mechanical and corrosion resistance. In this work, porous titanium samples obtained using a space-holder technique are coated with Chitosan, Chitosan/AgNPs and Chitosan/Hydroxyapatite using only one step and an economic electrodeposition method. The coatings’ topography, homogeneity and chemical composition were analyzed. A study of the effect of the porosity and type of coating on corrosion resistance and cellular behavior was carried out. The electrochemical studies reveal that porous samples show high current densities and an unstable oxide film; therefore, there is a need for surface treatments to improve corrosion resistance. The Chitosan coatings provide a significant improvement in the corrosion resistance, but the Chitosan/AgNPs and Chitosan/HA coatings showed the highest protection efficiency, especially for the more porous samples. Furthermore, these coatings have better adherence than the chitosan coatings, and the higher surface roughness obtained favors cell adhesion and proliferation. Finally, a combination of coating and porous substrate material with the best biomechanical balance and biofunctional behavior is proposed as a potential candidate for the replacement of small, damaged bone tissues.

Latest Trends in Surface Modification for Dental Implantology: Innovative Developments and Analytical Applications

“…Other authors incorporated the HA in a polymeric blend to obtain a composite coating with this antibacterial effect. Thus, García-Cabezón et al [113] deposited HA-containing chitosan nanofibers onto porous titanium implants. The use of this composite to cover the implant's surface would not only increase the osseointegration but would also prevent the corrosion of the implant.…”

The Importance of Chitosan Coatings in Dentistry

“…The most common problem with implant loss is periimplantitis around the metal part of the implant and the need for better osteointegration pairs with the need for an antimicrobial reaction. It has been proven that chitosan/AgNPs and chitosan/HA coatings protect the surface more effectively, especially when used on porous surfaces [38][39][40]. VEGF (vascular endothelial growth factor) plays a role in vascularization and osteoblastic differentiation as well as bone regeneration.…”

Development of porous silver nanoparticle/polycaprolactone/polyvinyl alcohol coatings for prophylaxis in titanium interconnected samples for dental implants

“…The substrates characteristics were: ρ = 2.15 g/cm 3 , P T = 51.8%, P i = 47.5%, D eq = 248 μm, F f = 0.85, E d = 22.9 GPa and σ y = 120 MPa. These values guarantee biomechanical (stiffness and mechanical resistance) and biofunctional (ability to promote bone ingrowth) equilibrium [47][48][49][50], as well as allowing infiltration and improving adherence of the different coatings [8,49].…”

“…An adequate surface coating could be a solution to mitigate the risk of infection, acting as a stable local drug delivery matrix system and, at the same time, improving implant biocompatibility or corrosion resistance [7]. In this sense, biodegradable, biocompatible, and non-toxic polymeric matrices, with a 'bonelike' surface, have already been proposed as degradable protective coatings [8] with potential for osseointegration and antibacterial function [9,10]. In particular, attention has been paid to the formation of three-dimensional polymeric matrices or scaffolds, capable of mimicking the structure of biological tissues at macro-, micro-, and nanoscales [11].…”