Guiding a tooth along an arch wire results in a counteracting frictional force among arch wires, bracket and ligature. This frictional forces should be eliminated or minimized when orthodontic tooth movement ; being planned.
The purpose of this study was to evaluate the changes of width, cross-sectional forms and surface morphologies of stainless steel wire and Elgiloy´ wire after electropolishing. Experimental variables included in this experiment were arch wire materials, current, electrolyte temperature and polishing time. Wire widths were measured by micrometer and cross-sectional forms and surface morphologies were examined with optical microscope and scanning electron microscope. The results were as follows.
1. The mean and standard deviation of widths of stainless steel wire and Elgiloya wire varying polishing time with condition of 249A/dm2 and 20C, 249A/dm2 and 25C, 332A/dm2 and 20C and 332A/dm2 and 25C were obtained.
2. With increasing polishing time, the widths of stainless steel wire and Elgiloya wire became decreased proportio. nally.
3. The changes of widths of stainless steel wire and Elgiloy´ wire were statistically insignificant between 20C group and 251C group, but significant between 249A/dm2 group and 332A/dm2 group.
4. The cross-sectional forms of wire after electropolishing were not changed in stainless steel wire, and while it were changed to rounded corners in Elgiloy wire.
5. The surface morphologies of wire after electropolishing were scratch-absent and more smoothened both in stain-less steel wire and Elgiloy wire.
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