The Comparison of Corrosion Behavior and Biocompatibility of a Ti-7.5Mo-6Al-5.8Zr-2Sn Alloy and TMA Orthodontic Wire: In Vitro Study

Biomaterial corrosion in the oral environment is of crucial importance. The present study aimed to investigate the difference between the corrosion behavior of a Titanium base alloy and TMA arch wire. Three sample types were studied in this case, a bulk version of the Ti alloy, a wire that was made by wire cutting, and the TMA arch wire. The EDX and AAS analysis showed that Ti alloy composition was Ti-7.5Mo-6Al-5.8Zr-2Sn and it had (α+β) phase. EIS, PDP and OCP tests were conducted on the artificial saliva. The obtained results showed that the bulk sample has corroded more than TMA arch wire, but the wire-shaped sample had almost the same corrosion behavior and polarization resistance. MTT Assay biocompatibility tests for cytotoxicity at 1, 7 and 30 days and flow-cytometry using Annexin V for the geno-toxicity at 5 months using human fibroblasts (HGF-1) showed that the optical density ranged from 0.7 to 1.25 and more than 80 % of cells were survived. ICP analysis for fibroblast cells in exposure to the samples at 5 month only indicated that Al and Mo lie in the range of ppm and the amount was lower than the risk range for human body.

Keywords:

Titanium base alloy , TMA archwire , EDX , Corrosion behavior , biocompatibility , ICP