Zirconium Surface Treatment via Chemical Etching

Abstract

The increased demand for implants that do not pose a threat to patients diagnosed using high-resolution magnetic resonance imaging and concerns arising from titanium allergies require the development of alternative implant materials. One promising concept is a use of zirconium as corrosion-resistant, nontoxic material that is lower in magnetic susceptibility. To achieve this, safe and efficient surface treatment methods of zirconium metal have to be developed. In this study, zirconium samples were treated with fluoride-free and fluoride-containing etching mixtures to determine their effect on the surface of Zr. SEM images were taken to investigate the preliminary effects of the etchants. Then, a second set of experiments was carried out using mixtures of HF-H2SO4 and ammonium persulfate–fluoride salts, as they gave the most promising results in the first trial. SEM images were taken and measurements on roughness, wettability, and atomic composition were made. The results showed an even zirconium surface in APS-fluoride salts, along with the formation of pits (1–3 μm) similar to those found in commercially available implants. There was no significant increase in the roughness of the treated samples. The addition of NO3− ions in the form of KNO3 speeded up etching and promoted pit formation. The HF-H2SO4 mixture was found to give unsatisfying results, as the surface was too rough and the formed pits were too large. It was concluded that etching zirconium in ammonium persulfate and fluoride salts is a promising area of research for the preparation of zirconium implants; however, further research has to be carried out on sandblasted samples.

Use of Ultra-Translucent Monolithic Zirconia as Esthetic Dental Restorative Material: A Narrative Review

“…This is one of the reasons glassceramic materials have been widely chosen for indirect veneer restorations, as they form a chemical link with the resin cement, in contrast to Zr restorations, which are chemically inert [69,70]. For this reason, various surface preparations have been suggested to alter the surface of zirconia and enhance adhesion to resin cement [71][72][73][74]. These techniques include airborne-particle abrasion (APA), tribo-chemical silica airborne-particle abrasion (TBS), laser irradiation, plasma spraying, Zr ceramic powder coating, low-fusion porcelain application, hot chemical etching solutions, and selective infiltration etching (SIE) [74].…”

“…The bonding ability would then be increased by putting Zr primer, such as MDP, onto the Zr bonding surface, which would naturally be effective in bonding with metal oxides. It is essential to use dual-or self-cure resin cement to ensure sufficient polymerization [69][70][71][72][73][74][75][76]. However, it is worth noting that when using a 0.5 mm thin monolithic Zr veneer material, it is necessary to increase the resin composite's curing time by about 40% over what it would be if the Zr ceramics were not used.…”