Slot deformation of various stainless steel bracket due to the torque force of the beta-titanium wire

1st Physics and Technologies in Medicine and Dentistry Symposium

物理学;医药卫生

Huda, M.M.^1 ; Siregar, E.^1 ; Ismah, N.^1

Department of Orthodontics, Faculty of Dentistry, Universitas Indonesia, Jakarta, Indonesia^1

关键词: 17-4 PH stainless steel;    Manufacturing process;    Measurement apparatus;    Metal composition;    Metal injection molding;    Orthodontic treatments;    Permanent deformations;    Slot measurement;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/884/1/012105/pdf
DOI  :  10.1088/1742-6596/884/1/012105

学科分类：卫生学

来源: IOP

【 摘 要 】

Stainless steel bracket slot deformation ffects the force applied to teeth and it can impede tooth movement and prolong orthodontic treatment time. The aim of this study is to determine the slot deformation due to torque of a 0.021 x 0.025 inch Beta Titanium wire with a torsional angle of 30° and 45° for five different bracket brands: y, 3M, Biom, Versadent, Ormco, and Shinye. The research also aims to compare the deformation and amount of torque among all five bracket brands at torsional angles of 30° and 45°. Fifty stainless steel edgewise brackets from the five bracket group brands (n=10) were attached to acrylic plates. The bracket slot measurements were carried out in two stages. In the first stage, the, deformation was measured by calculating the average bracket slot height using a stereoscopy microscope before and after application of torque. In the second stage, the torque was measured using a torque measurement apparatus. The statistical analysis shows that slot deformations were found on all five bracket brands with a clinical permanent deformation on the Biom (2.79 μm) and Shinye (2.29 μm) brackets. The most torque was observed on the 3M bracket, followed by the Ormco, Versadent, Shinye, and Biom brackets. When the brands were compared, a correlation between bracket slot deformation and the amount of torque was found, but the correlation was not statistically significant for the 3M and Ormco brackets and the Biom and Shinye brackets. There is a difference in the amount of torque between the five brands with a torsional angle of 30° (except the 3M and Ormco brackets) and those with a torsional angle of 45°. The composition of the metal and the manufacturing process are the factors that influence the occurrence of bracket slot deformation and the amount of torque. A manufacturing process using metal injection molding (MIM) and metal compositions of AISI 303 and 17-4 PH stainless steel reduce the risk of deformation.