Changes in the corrosion rate and microstructure of nickel titanium wire in pandan leaves extract.

Abstract

Objective: This study aimed at determining the effect of pH changes on nickel titanium wire seen based on the corrosion rate and surface roughness of the wire after immersion in pandan leaves extract.

Material and methods: The sample used nickel titanium wire of 0.016 inches diameter and 5 cm length and consists of five treatment groups: control group, 0.2% chlorhexidine, and 1000 ppm, 2000 ppm, and 4000 ppm pandan leaves extract. The solutions were put into an incubator for 7, 14, and 21 days at 37 °C and removed according to the sample immersion time. The corrosion rate was determined using the weight-loss method, and microstructure roughness was analyzed using a scanning electron microscope.

Results: Kruskal-Wallis test showed that there was a significant difference in corrosion rate of orthodontic wires of nickel titanium after control submersion, 0.2% chlorhexidine, and pandan leaves extract on 7, 14, and 21 days (P ≤ 0.05), and pandan leaves extract submersion shows that the surface structure is not as bad as artificial saliva and 0.2% chlorhexidine.

Conclusions: Pandan leaves extract could inhibit the corrosion rate of nickel titanium orthodontic wire, which might be due to tannin content as an active antioxidant.