Evaluation of frictional resistance of different types of tooth colored orthodontic brackets

Abstract

Objective. To compare the frictional properties of three different types of tooth colored brackets with arch wire.
Material and methods: A total of 21 conventionally ligated first premolar aesthetic brackets were used in this study. The samples were divided into 3 main groups (7 each) according to bracket material: group (I) Plastic Bracket with metal slot , group(II) monocrystalline alumina bracket, group (III) polycrystalline alumina bracket . Single upper first premolar brackets were mounted on a custom-made acrylic fixture and straight section of rectangular stainless steel (SS) arch wire 0.019″ × 0.025″ were ligated to the bracket with conventional elastomeric ligature. Frictional resistance (FR) was measured with an Instron universal testing machine. The data was statistically analyzed using one-way ANOVA and Tukey’s pairwise tests.
Results. Statistical results showed that FR generated by the plastic bracket (307.7±23.9 gr)with metal slot was significantly lower than that generated with the ceramic bracket (mono and polycrystalline ceramic) and showed the lowest FR with the SS wires ,this was followed by polycrystalline ceramic bracket(366.6±53.9 gr) which generated smaller amount of FR but relatively on the higher side when compared with plastic bracket with metal slot .Monocrystalline bracket generated the maximum amount of FR (680±16.2 gr) when compared to other type of esthetic brackets.
Conclusion: The study demonstrated that plastic brackets with metal slot showed the least frictional resistance of the three-type bracket used.