The Influence of Angulation Between Stainless Steel Wires and Stainless Steel Brackets on Friction Resistace
M. Nasser Sawan, Kinda Sultan · 2010
Introduction: frictional forces interfere with the nature of orthodontic tooth movement during sliding techniques, while many factors affect on this frictional forces. Aim of study : this laboratory investigation was made to study one of the important factors influencing frictional resistance; that is the angulation between the bracket and the orthodontic wire. Materials and methods: 40 couples (stainless steel bracket 0.018 /stainless steel wire 0.016x0.016) have been studied using special apparatus which was designed under the supervision of faculty of mechanical engineering-Damascus university. The frictional resistance was measured during sliding the bracket along the orthodontic wire with four different angulations : 0-3-7-10 degree. Results: Statistical analyses showed general increase in the frictional resistance as the angulation between the bracket and wire increases during the sliding movement. In passive configuration where the angulation between the arch wire and bracket is less than the critical angulation; the effects of the different angulations on the frictional resistance were little as there were no statistically significant differences between the frictional forces recorded in the angulations 0-3 degree. Whereas extremely increase in frictional forces was noticed when the angulation exceeded the critical value (active configuration). There were statistically significant differences (p<.001) between 0 and both 7and 10 angulations, between 3 and both 7and 10 angulations, and between 7and 10 angulations.