PENGARUH BESAR KOMPRESI DAN LAMA PERENDAMAN DALAM SALIVA BUATAN TERHADAP KEKUATAN OPEN COIL SPRING NIKEL TITANIUM

Abstract

Open coil spring consist of the active component spring is often used in the treatment of fixed orthodontic shaped metal coils. The study aimed to determine the effect of compression and immersion time in the artificial saliva of the open coil spring strength.
Subject of study consist of  30 nickel titanium open coil spring. Length of each is 12 mm dimention size 0,01×0,03 inch mm with a pitch distance 0,02 mm. The subject is divided into 3 groups, group A with ¼ compression initial length, group B with
1/3 compression initial length and group C with 1/2 compression initial length. All subjects in each group were immersed in artificial saliva and measured strength at 1 day, 7 days, 21 days and 28 days. Strength measurements performed by Tensile Testing Machine. Strength is measured in Newton and using two way anova statistical test to know determine the effect of compression and immersion time in the saliva of the open coil strength.
Two way anova test results showed that there were significant differences (p<0,05) between high strength compression of the nickel titanium  open coil strength. There are significant differences (p<0,05) between different immersion time to nickel
titanium open coil strength. Conclusion there is influence on the initial length of the ½,1/3,1/4 compression open coil spring strength and there is influence on 1 day with 21 days,1 day with 28 days and 7 days with 28 days immersion time in the strength of open coil spring.