Analysis on surface modification of orthodontic power chain by nanoimprinting process

The traditional orthodontic power chain, usually made of polymer materials, exists some drawbacks, such as the reduction of elasticity due to swell after absorbing water and surface discoloration resulting from the patient's diet, food, or beverage colors leading to poor appearance. The main purpose of this study was to develop surface modification on orthodontic power chain and to realize the properties change for improvement of its shortcomings. In this study, a template was produced by pure aluminum piece with anodized production (concave) through the nanoimprinting process fabricating nanostructures (convex) on the surface of power chain, resulting in surface modification of power chain. The different nanoimprinting process parameters (e.g., imprinting temperature, imprinting pressure, imprinting time, and demolding temperature) were used to produce nanostructures on the surface of power chain. The results of this study show that the contact angle of the power chain became larger after nanoimprinting surface treatment. The hydrophilic properties of power chain have been turned into hydrophobic properties. Unmodified power chain before water absorption is about 4%, while a modified water absorbance is about 2%-4%.