Research of changes in surface frictional forces and surface topography of orthodontic stainless steel archwires after application in oral conditions

Abstract

Objective The purpose of this study was to investigate the changes of surface frictional forces and surface topography of used-stainles steel(ss) archwires. Method On the testing mandibular model,we measured the static and kinetic friction between the used and unused archwires at different time points and they were examined in the space closure phase. Surface topography of each type archwire was assessed by scanning electron microscope(SEM). Results The surfacial friction of ss archwires used three months are greater than the unused one (P＜0. 05), while much greater than that used after four and five months (P＜0. 01). SEM: The surfacial smooth finish of ss archwires were reduced with the longer time of use, whereas surface roughness were increased. Conclusion The roughness changes on the ss archwires' surfacial structure suggested us to change the archwires in time or increase the anchorage. Key words: Surface frictional forces; Archwire surfacial structure; Oral conditions; Stainles steel archwire