Effect of Pickles on the Validity Period of Orthodentic Wires

Abstract

The summery of this research is to determine the longest validity period of the orthodentic wires used in three corrosive media. The first was similar to human mouth such as corrosive medium (artificial saliva), human temperature, aeration and acidity (pH), in comparison with the second corrosive medium was Khelic acid solution (CH3COO) only at same temperature and aeration above. The final comparison with the third corrosive medium was mixture of artificial saliva with khelic acid solution at same human temperature and aeration too. This study was achieved by using corrosion system was locally designed and made according to modified American standard (ASTM G31) .The orthodentic wires in this research type (AISI 301). By using the Corrosion Penetration Rate formula (CPR), traditional mathematical methods after three corrosion tests mentioned for six months in sequent and by using microstructures of samples before and after those tests. It was found the longest validity period of orthodentic wires was in medium which similar to human mouth (65.324 yr.) then wires in khelic acid solution only at same human temperature and aeration (32.982 yr.), and shortest validity period of wires was in third medium (mixture of artificial saliva and khelic acid solution at same human temperature and aeration) (15.863 yr.).The longest validity period was in the first state because in which corrosion less (50%) than the second state and less (86%) than the third state.