Surface treatments of Ti-alloy based bone implant manufactured by electrical discharge machining

Objective: This research aims to observe the extent to which several surface treatment techniques increase the surface roughness of titanium alloy implants which was manufactured via electrical discharge machining (EDM). The effects of these techniques were also observed to decrease the Cu content on the implant surface. Materials and Methods: In this research, ultrasonic cleaning, rotary tumbler polishing, and brushing were employed as techniques to increase the roughness of a titanium implant which was manufactured via EDM, to the moderately rough category, and to reduce the contaminant element deposited on its surface. An MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay test was also used to observe the effect of these engineered specimens with respect to mesenchymal stem cells’ proliferation. Results and Discussion: The results show that ultrasonic cleaning and rotary tumbler polishing created a significant increase (90% and 67%, respectively) in the surface roughness. On the other hand, brushing was shown to be the best benchmark for reducing the contamination of Copper (Cu). Furthermore, rotary tumbler polishing and brushing can increase the percentage of living cells compared to the original surface EDM specimens. Conclusion: All micro-finishing methods that were employed are able to increase the surface roughness of Ti alloy based-implant to moderately rough category.