Orthodontic Bracket Slot Deformation While Torqueing in a Bracket- Archwire Segment Assembly: An FEA Study

Abstract

Orthodontics is a field of dentistry treating malocclusions using fixed appliances consisting of a brackets, archwires, ligatures etc. Few studies showed the tie wings and slot deformation of single orthodontic bracket-archwire assembly. The objective of this study was to analyse the slot deformation in two orthodontic brackets-archwire segments during torque.  Conventional 0.018-inch Stainless Steel (SS) and Titanium (Ti) brackets were modelled using a reverse engineering approach. Modelled brackets-archwire segment assemblies were meshed using Finite Element Analysis (FEA) software. SS archwire was torqued (twisted) from 0^o to 30^o with 5^o increments. The brackets slot deformation in the top, middle and bottom locations of the slots were measured using FEA software. The 0.017″ × 0.025″ SS archwire with 0.018″ width Ti bracket showed the maximum deformation of 54.03 µm in the top location of slot, whereas the 0.016″ × 0.022″ SS archwire with 0.018″ SS bracket showed the minimum deformation of 21.87 µm in the top location of slot.   This in-silico study visualizes the slot deformation in a two bracket-archwire system similar to clinical situation during segmental torque.