Etched Titanium Surface Research Articles

Effect of organic self-assembled monolayers on the deposition and adhesion of hydroxyapatite coatings on titanium

Abstract Organic self-assembled monolayers with nitrogen-containing surface functionalities (amine or alkylammonium) were deposited on acid-etched titanium substrates. These were then coated with apatite deposited from 150% simulated body fluid at 37°C and pH = 7.6 for 2, 4, and 6days (after a 2-day “nucleation” step in contact with bioactive glass in 100% simulated body fluid). Scanning electron microscopy showed that precipitates were numerous on amine- and alkylammonium-modified titanium surfaces after nucleation for 2 days. X-ray diffraction at grazing incidence detected crystalline hydroxyapatite on the modified and unmodified substrates after growth for 2days. Tape peel tests followed by surface chemical analysis showed that the adhesion of the hydroxyapatite coating to the substrates was improved by amine and by alkylammonium modification of the etched titanium surfaces.

Electrophoretic Deposition of Hydroxyapatite Nano Coating on Etched Titanium Surface

Hydroxyapatite (Ca10(PO4)6(OH)2, HAp) is biocompatible and bioactive, however, it is relatively brittle. The development of HAp coatings on medical metal surface is a good way to improve the mechanical properties of HAp. In the present study, a HAp coating with nano-structure on a roughened titanium surface was developed by electrophoretic deposition process. To decrease sintering temperature HAp nanoparticles synthesized by a wet chemical method was used. It was observed that the coating was uniform and showed no cracks. After sintering the HAp coating still remained nano structured. The surface treatment of Ti was applied to form a distribution of small pits and a TiO2 thin layer on the Ti surface that improves the adhesion of coating to the Ti substrate. It was shown that the bonding strength of coating was 18 ± 2.5MPa. The hardness and Young’s modulus were 40.6 and 0.42 GPa, respectively.

Immunolocalization of fibronectin and vitronectin receptors in human gingival fibroblasts spreading on titanium surfaces.

The adhesion and spreading of human gingival fibroblasts on glass and differently processed titanium surfaces was studied by immunolocalization of vinculin and the alpha and beta subunits of the fibronectin (alpha 5 beta 1) and (alpha v beta 3) receptors. Vinculin-containing focal contacts were present both at 4 and 24 h of spreading in cells grown on glass or electropolished or etched titanium surfaces but not in cells spreading on sandblasted titanium surfaces. Immunostaining for the alpha 5 and beta 1 subunits of the fibronectin receptor showed only a diffuse membrane fluorescence after 4 h of cell spreading irrespective of the growth surface. The alpha v and beta 3 subunits of the vitronectin receptor were at this stage detected in focal contacts in cells spreading on glass or electropolished or etched titanium surfaces. In cells spreading on sandblasted titanium surfaces, however, the vitronectin receptor had only a diffuse distribution. In cells that had been allowed to spread for 24 h on glass or electropolished or etched titanium surfaces the alpha 5 and beta 1 integrin subunits were either diffusely distributed or showed a localization typical of extracellular matrix contacts. The alpha v and beta 3 integrin subunits were, as earlier, localized to typical focal contacts in cells grown on glass or electropolished or etched titanium surfaces. Cells attached to sandblasted titanium surfaces still expressed all the integrin subunits only diffusely. The results show that the surface texture of the substratum can affect the expression of integrin subunits in human gingival fibroblasts.(ABSTRACT TRUNCATED AT 250 WORDS)