Impact of recycling on efficiency and efficacy of copper nickel titanium wire and heat activated nickel titanium wire – An invitro study

The aim of the study is to assess the feasibility of reusing copper nickel titanium wire and heat activated nickel titanium wires by evaluating the changes in efficiency and efficacy of wire after different sterilization techniques. 120 total samples were taken. 60 samples of Damon copper nickel titanium (ORMCOTM) and 60 samples of heat activated nickel titanium wires (ORMCOTM). Damon CuNiTi and HANT were divided in 4 different sub groups of 15 samples each. 15 as received wires served as controlled group. The remaining wires were placed intraorally for a period of 4 weeks in patients undergoing orthodontic treatment. After 4 weeks, these wires were taken out. Remaining 45 wires were divided on the basis of sterilization method to be used. (autoclave, 70% isopropyl alcohol, 2% glutaraldehyde solution). Maximum load and tensile strength were tested using universal testing machine. No significant difference in mechanical properties of wires after various sterilization process (p value > 0.05). There no such difference in mechanical properties of controlled group wires and wires those are placed intraorally for 4 weeks. Results suggested that there was no statistically significant difference in the Ultimate Tensile Strength and Maximum Load of Damon Copper Nickel-Titanium wire and Heat Activated Nickel Titanium wire following various sterilization procedures. These wires can be reused after sterilization.