Evaluation of Maxillary Transverse Arch Dimensions Following Leveling and Alignment with Different Archwire-Bracket Combinations During Fixed Appliance Treatment - A Retrospective Study

Background- Arch expansion is one of the non- extraction methods of gaining space. This study aims to assess and compare the arch expansion achieved during initial leveling and alignment with three different bracket-archwire combinations. Material and Methods- This was a retrospective study done in a university setup. From the available patient information archives, records of 30 subjects based on their advocated bracket system were identified and categorized into three groups. Their pre-treatment (T0) and post aligning (T2) 3D model maxillary scans were superimposed according to the reference points marked on the third palatal rugae using an OrthoAnalyzer software(3 shape version 19.0) to assess the changes in Intercanine width (ICW), Inter-premolar width (IPW) and Intermolar width (IMW) and arch length. For the recorded data, descriptive statistics, One-way ANOVA and Tukey HSD post hoc were analyzed using SPSS software.  Results- Except for the Damon group that showed considerable increase in the intermolar and premolar dimensions, other groups had no statistically significant differences in terms of Intercanine width, Interpremolar width, and Intermolar width and Arch length. Conclusion- Changes in the transverse dimension were noticed among all the three groups with maximum in the Damon bracket and Damon archwire combination. Although the difference in expansion between groups showed no statistically significant difference, it was appreciated clinically in relieving dental crowding.