Comparative Analysis of Slot Deformation Between Orthodontic Brackets with Varied Tie Wings

Abstract

Orthodontics deals with the treatment of malocclusion of teeth using orthodontic brackets, archwires, and ligatures etc. as components of fixed appliances. Orthodontic brackets are available with different geometry, material and tip / torque prescription. Bracket slot may be prone for deformation due to the archwire torqueing forces. The aim of this study was to analyse the slot deformation between Four Tie Wings (4-TW) and Six Tie Wings (6-TW) brackets using Finite Element Analysis (FEA). Stainless Steel (SS) 0.022″ preadjusted 4-TW and 6-TW brackets along with SS 0.021″ × 0.025″ archwires were modelled by reverse engineering approach. In the Finite Element (FE) model, the archwires were twisted from 5^o to 40^o. The deformation in the Top Location of Slot (TLS) and Middle Location of Slot (MLS) of 4-TW and 6-TW brackets were measured. Results showed that the slot deformation of the 6-TW bracket was 2.57 times lesser than 4-TW bracket. The maximum deformation was seen in the TLS compared to MLS in both the brackets. Our FEA study showed that the 6-TW brackets are better than 4-TW brackets in relevance to slot deformation and thus advantageous in reducing the torque loss.